Rules for the Design of Hoisting Appliances

FEDERATION EUROPEENNE DE LA MANUTENTION

SECTION I

HEAVY LIFTING APPLIANCES

F.E.M.

1.001 3rd EDITION

REVISED 1998.10.01

RULES FOR THE DESIGN OF

HOISTING APPLIANCES

B O O K L E T 1

OBJECT AND SCOPE

The total 3rd Edition revised comprises booklets 1 to 5 and 7 to 9 Copyright by FEM Section I

Also available in French and German

File is licenced for ISKAR Mühendislik Ltd. - Order-no: 401195 - 1License(s)

http://www.vdma-verlag.com/home/

Booklet 1

OBJECT AND SCOPE

1.1. PREFACE.............................................................................................................................. 2

1.2. INTRODUCTION ................................................................................................................... 3

1.3. OBJECT OF THE RULES ..................................................................................................... 5

1.4 SCOPE .................................................................................................................................. 6

LIST OF SYMBOLS AND NOTATIONS .......................................................................................... 7



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1.1. PREFACE

The Rules for the Design of Hoisting Appliances set up by the Technical Committee of the Section Iof the F.E.M., which have been published so far in two Editions, the first one in 1962 and thesecond in 1970, have been increasingly widely used in many countries all over the world.

Taking accourt of this enlarged audience, Section I of the FEM decided to change the format ofthese Design Rules and to facilitate updating by abandoning the single volume form and dividingthe work into a number of separate booklets as follows :

Booklet 1 - Object and Scope

Booklet 2 - Classification and loading on structures and mechanisms

Booklet 3 - Calculating the stresses in the structure

Booklet 4 - Checking for fatigue and choice of mechanism components

Booklet 5 - Electrical equipment

Booklet 6 - Stability and safety against movement by the wind

Booklet 7 - Safety rules

Booklet 8 - Test loads and tolerances

Although not directly a part of these Design Rules, the opportunity is taken to draw attention to thenew Terminology of Section I.



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1.2. INTRODUCTION

To facilitate the use of these Rules by the purchasers, manufacturers and safety organizationsconcerned, it is necessary to give some explanation in regard to the two following questions.

1. How should these Rules be applied in practice to the different types of appliance whoseconstruction they cover ?

2. How should a purchaser use these Rules to define this requirements in relation to anappliance which he desires to order and what conditions should he specify in this enquiry toensure that the manufacturers can submit a proposal in accordance with tris requirements ?

1. It is necessary first to recognize the great variety of appliances covered by the Design Rules. Itis obvious that a crane having very high speeds and a rapid working cycle is not designed in thesame manner as a small overhead crane for infrequent duty. For such a machine there can beno question of making all the verifications which would appear to be required, from readingthrough the Rules, because one would clearly finish with a volume of calculations which wouldbe totally out of proportion to the objective in view. The manufacturer must therefore decide ineach particular case which parts of the machine, which he is designing, should be analysed andthose for which calculation is unnecessary, not because he must accept that the results for thelatter would not be in accordance with the requirements of the Rules, but because on thecontrary he is certain in advance that the calculations for the latter would only confirm afavourable outcome. This may be because a standard compornent is being used which hasbeen verified once and for all or because it has been established that some of the verificationsimposed by the Rules cannot in certain cases have an unfavourable result and therefore serveno purpose.

If one takes, for exemple, the fatigue calculations, it is very easy to see that certain verificationsare unnecessary for appliances of light or moderate duty because they always lead to theconclusions that the most unfavourable cases are those resulting from checking safety inrelation to the elastic limit.

These considerations show that calculations made in accordance with the Rules can take a verydifferent form according to the type of appliance which is being considered, and may in the caseof a simple machine or a machine embodying standard components be in the form of a briefsummary without prejudicing the compliance of the machine with the principles set out by theDesign Rules.

2. As far as the second question is concerned, some explanation is first desirable for thepurchaser, who may be somewhat bewildered by the extent of the document and confusedwhen faced with the variety of choice which it presents, a variety which is, however, necessary ifone wishes to take account of the great diversity of problems to be resolved.



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In fact, the only important matter for the purchaser is to define the duty which he expects from hisappliance and if possible to give some indication of the duty of the various motions.

As regards the service to be performed by the appliance, two factors must be specified, i.e. :

- the class of utilization, as defined in 2.1.2.2 ;

- the load spectrum, as defined in 2.1.2.3.

In order to arrive at the number of hoisting cycles determining the class of utilization, the purchasermay, for instance, find the product of :

- the number of hoisting cycles which the appliance will have to average each day on which it isused ;

- the average number of days of use per year ;

- the number of years after which the appliance may be considered as having to be replaced.

Similarly, the load spectrum may be calculated by means of the simplified formula set out in theabove mentioned paragraph.

In neither case do the calculations call for a high degree of accuracy, being more in the nature ofestimates than of precise calculations. Moreover, the numbers of hoisting cycles determining theclasses of utilization do not constitute guaranteed values : they are merely guide values, serving asa basis for the fatigue calculations and corresponding to an average life which can be expectedwith a reasonable degree of safety, provided the appliance, designed in accordance with thepresent design rules, is used under the conditions specified by the customer in his call for tenderand also that it is operated and maintained regularly in compliance with the manufacturer'sinstructions.

If he is unable to determine the class of utilization and the load spectrum, the purchaser mayconfine himself to stating the group in which the appliance is to be classified. A guide as to thechoice of group is provided by Table 2.1.2.5., which is not binding but gives simple exempleswhich, by way of comparison, may facilitate selection.

In the case of mecanisms, the following should also be specified :

- the class of utilization, as specified in 2.1.3.2. :

- the load spectrum, as defined in 2.1.3.3. :

the same observation apply as were made concerning the appliance as a whole.



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The tables in Appendix A.2.1.1. may be used to facilitate determination of the class of utilization.On the basis of the class of utilization of the appliance, they make it possible to determine a totalnumber of working hours for the mechanism, according to the average duration of a working cycleand the ratio between the operating time of the mechanism and the duration of the complete cycle.

Table T.2.1.3.5. may be used as a guide by a purchaser wishing simply to choose a group for eachof the mechanisms with which the appliance he wants to order is to be fitted.

As a general rule, the purchaser has no other information to supply in connection with the design ofthe appliance, except in certain cases :

- the area of hoisted loads presented to the wind, if this area is larger than those defined in2.2.4.1.2. ;

- the value of the out-of-service wind, where local conditions are considered to necessitatedesign for an out-of-service wind greater than that defined in 2.2.4.1.2.

1.3. OBJECT OF THE RULES

The purpose of these rules is to determine the loads and combinations of loads which must betaken into account when designing hoisting appliances, and also to establish the strength andstability conditions to be observed for the various load combinations.



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1.4 SCOPE

The Rules apply to the design of lifting appliances or parts of lifting appliances which appear in theillustrated terminology for cranes and heavy lifting appliances of Section I of the FEM.

Appliances not covered by Section I

1) Lifting appliances included in Section V, for exemple :

- mobile jib cranes on pneumatic or solid rubber tyres, crawler tracks, lorries, trailers andbrackets.

2) Lifting equipment which according to the internal regulations of FEM, are included in Section IX,that is to say :

- various items of series lifting equipment,

- electric hoists,

- pneumatic hoists,

- accessories for lifting,

- hand operated chain blocks,

- elevating platforms, work platforms, dock levellers,

- winches,

- jacks, tripods, combined apparatus for pulling and lifting,

- stacker cranes.

For series lifting equipment, those chapters of the Design Rules of Section I which have beenaccepted by Section IX should be used.

These rules comprise eight booklets. In addition some booklets contain appendices which givefurther information on the method of application.



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LIST OF SYMBOLS AND NOTATIONS

Symbol Unit Désignation Paragraphe

A m2 Area exposed to wind 2.2.4.1.

A - Combined influence of residual tensile stresses with dead weightstresses 3.1

A1 à A8 - Crane groups 2.1.2

Ae m2 Enveloped area of lattice 2.2.4.1.4

a mm Wheelbase of crane :Dimension of lattice in wind load calculation :Length of strip of plate in buckling calculation :Size of fillet weld in notch case 2.33

2.2.2.32.2.4.1.4A-3.4T.A.3.6.-2.33

a m/s2 Acceleration 5.8.3.1

B - Influence of thickness of structural member 3.1.1.2

B mm Width of lattice in wind load calculation 2.2.4.1.4

B0 à B10 - Classes of utilization of structural members 2.1.4.2

b mm Breadth of section across wind front :Largest dimension of rectangular steel section :Length of plate in buckling calculation :Useful width of rail in wheel calculation

2.2.4.1.43.1.1.2A-3.44.2.4.1

C - Influence of cold :Coefficient used to calculate the tightening torque of bolts :Selection coefficient for choice of running steel wire ropes

3.1.1.3A-3.2.2.2.2.34.2.2.1.3.1

Cf - Shape coefficient in wind load calculation 2 2.4.1.4

c, c' - Factors characterising the slope of Wöhler curves 4.1.3.5

c1, c1max - Rotation speed coefficients for wheel calculation 4.2.4.1

c2, c2max - Group coefficient for wheel calculation 4.2.4.1

cos ϕϕϕϕ - Power factor 5.2.3.3.2

D - Symbol used in plate inspection for lamination defects T.A.3.6

D m Section diameter in shape factor determination 2.2.4.1.4

D mm Rope winding diameter :Wheel diameter :Shaft diameter in fatigue verification of mechanism parts .

4.2.3.14.2.4.1A-4.1.3



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Dt mm Diameter of bolt holes 3.2.2.2.1

d mm Depth of section parallel to wind direction in wind load calculation :Nominal diameter of bolt :Nominal diameter of rope :Shaft diameter in fatigue verification of mechanism parts

2.2.4.1.4A-3.2 .2 .2 .34.2.2.1.3A-4.1.3

d2 mm Bolt diameter at thread root 3.2.2.2.1

dc - Number of completed starts per hour 5.8.1.4

di - Number of impulses or incomplete starts per hour 5.8.1.4

dmin mm Minimum rope diameter A-4.2.2

dt mm Nominal bolt diameter 3.2.2.2.1

E N/mm2 Elastic modulus of steel A-3.4

E1 à E8 - Groups of components 2.1.4.1

ED % Duty factor 5.8.1.4

e mm Thickness of strip of plate in buckling calculation :Thickness of plate in welded joints

A-3.4T.A-3.6-2.31

e1, e2 mm Plate thicknesses in welded joints A-3.4

F N Wind force :Horizontal force during acceleration :Tensile load in bolts :Compressive force on member in crippling calculation

2.2.4.1.2A-2.2.33.2.2.2.2A-3.3

F0 N Minimum breaking load of rope 4.2.2.1.2

F1 N Permissible working load on bolts 3.2.2.2.1

Fc N Projection of rope load on the x axis during travelling A-2.2.3

Fcm N Inertia force due to the load during travelling A-2.2.3

Fcmax N Maximum value of Fc A-2.2.3

f - Fill factor of rope 4.2.2.1.3

fcy Number of electrical brakings 5.8.1.4

g m/s2 Acceleration due to gravity. according to ISO 9.80665 m/S2 A-2.2.3

H - Coefficient depending on group for choice of rope drums andpulleys 4.2.3.1.1

I kgm2 Moment of inertia of mass in slewing motion A-2.2.3.-3



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I1, I2 mm4 Moment of inertia of stiffeners A-3.4

ID A Starting current of motor 5.2.3.3.2

IN A Nominal current of motor 5.2.3.3.1

Itot A Sum of currents IA and IN 5.2.3.3.2

IZ mm4 Moment of inertia of stiffeners A-3.4

Ii kgm2 Moment of inertia of mass of a part in rotation A-2.2.3

Im kgm2 Moment of inertia of mass of all parts in rotation A-2.2.3.-2.1

JM kgm2 Moment of inertia of mass of motor and brake 5.8.1.4

j - Group number in component groups E1 to E8 4.1.3.6

j0 m/s2 Acceleration in horizontal motions A-2.2.3.-2.2

jm m/s2 Average acceleration/deceleration in horizontal motions A - 2.2.3

K’ - Empirical coefficient for determining minimum breaking strength ofrope 4.2.2.1.3

K0 à K4 - Stress concentration classes for welded parts A-3.6

K2 - Coefficient for calculating force in the direction of the wind forlattice girders and towers 2.2.4.1.4.4

KL N/mm2 Pressure of wheel on rail 4.2.4.2

Km - Mn med / M max 4.2.1.2

k - Spinning loss coefficient 4.2.2.1.3

kc - Corrosion coefficient in fatigue verification of mechanism parts A-4.1.3

kd - Size coefficient in fatigue verification of mechanism parts A-4.1.3

km - Spectrum coefficient for mechanisms 2.1.3.3

kp - Spectrum coefficient for cranes 2.1.2.3

ks - Shape coefficient in fatigue verification of mechanism parts 4.1.3.3

ksp - Spectrum coefficient for components 2.1.4.3

k’sp - Spectrum coefficient for mechanism parts 4.1.3.5

ku - Surface finish (machining) coefficient in fatigue verification ofmechanism parts 4.1.3.3



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Kσσσσ Kττττ - Buckling coefficients used in buckling calculations A-3.4

L N Maximum permissible lifting force 5.8.2.1

L1 à L4 - Spectrum classes for mechanisms 2.1.3.3

l m Length of suspension/length of load pendulum A-2.2.3.-2

l m Equivalent length of fine 5.2.3.3.2

l m Length of members in wind force calculations :Overall width or rail head

2.2.4.1.4.14.2.4.1.2

lk m Length of parts tightened in bolted joints 3.2.2.2.1

M N.m External moment in bolted joints 3.2.2.2.2

M1 à M8 - Mechanism groups ; 2.1.3.1

M1,M2, M3 - Motor torques required during a cycle of operations 5.8.1.3.1

MF N.m Braking torque of motor 5.8.2.1

MNmax N.m Maximum running torque required to lift the load 5.8.2.1

Ma N.m Torque required to tighten bolts A-3.2.2.2.2.3

MF N.m Bending moment in member in crippling calculation A-3.3

Mmax N.m Maximum value of motor torque 5.8.2.1

Mmed N.m Mean value of torque M during motor running time fiT 5.8.2.1

Mmin N.m Minimum motor torque during starting 5.8.2.1

m - Number of friction surfaces in bolted joints 3.2.2.2.2

m kg Equivalent mass for calculating loads due to horizontal motions :Total mass of crane

A-2.2.3.-1A-2.2.3.-2

m0 kg Mass of crane without load A-2.2 .3.-1

ml kg Mass of the load A-2.2 .3.-1

mL kg Mass of the hook load 5.8 .3.1

me kg Equivalent mass in calculation of loads due to horizontal motion A-2.2.3.-2.1

m kg Load 2.1.2.3

mlmax kg Safe working load 2.1.2.3



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N - Number of hoisting cycles A-2.1.1

N N Force perpendicular to joint plane in bolted joints 3.2.2.2.2

NG - Ordinary quality in welding 3-57 $$$$$

NM N Tensile force due to external moment in bolted joints 3.2.2.2.2

n - Number of hoisting cycles :Number of stress cycles

2.1.2.34.1.3.5

n min-1 Nominal rotation speed of motors in rpm 5.8.1.4

nmax - Number of hoisting cycles determining the total duration of use 2.1.2.3

P N Load on wheel 4.2.4.2

P1 à P4 - Spectrum classes for components 2.1.4.3

P10, P100 - Symbols indicating welding tests T.A-3.6

PL N/mm2 Limiting pressure in wheel calculation 4.2.4.1

PN W Nominal power of motor 5.8.1.4

PNmax W Maximum power requirement of motor 5.8.2.1

Pmoy I, II N Mean load on wheel in loading cases I and II 4.2.4.1

Pmoy III N Mean load on wheel in loading case III 4.2.4.1

Pmin I, II, III N Minimum load on wheel in loading cases I, II and III 4.2.4.1

Pmax I, II,III N Maximum load on wheel in loading cases I, II and III 4.2.4.1

Pmed kW Equivalent mean power 5.8.1.3.2

p mm Span of crane 2.2.3.3

pa mm Pitch of thread 3.2.2.2.1

Q1 à Q4 - Spectrum classes for cranes 2.1.2.3

q - Correction factor for shape coefficient ks A-4.1.3

q N/mm2 Dynamic pressure of the wind 2.2.4.1.1

R0 N/mm2 Minimum ultimate tensile strength of the wire of a rope 4.2.2.1.3

RE N/mm2 Apparent elastic limit σE according to ISO 3800/1 3.2.2.2.1

r - Number of levers of loading :Ratio of stresses for large deformations

2.1.3.33.5



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r mm Radius of cylindrical shells in buckling calculations :Radius of rope groove :Radius of rail head :Blending radius

A-3.44.2.3.24.2.4.1.2A-4.1.3

r Ω/km Ohmic resistance per unit length 5.3.2

S N Stress :Maximum tensile force in rope

2.1.3.3 4.2.2.1.1.2

S m2 Area of all members of lattice girders and towers 2.2.4.1.4.4

S mm2 Cross sectional area of conductor 5.2.3.3.2

S1 mm Bearing diameter under bolt head 3.2.2.2.1

SG N Load due to dead weight. constant load . 2.2.1 & 3.5

SH N Load due to horizontal motions 2.2.3

SL N Load due to working load 2.2.1

SM N Load due to torques 2.5

SMmoy N Mean type M load in bearing calculation 4.2.1.2

SMmin N Minimum type M load in bearing calculation 4.2.1.2

SMmax I N Maximum type M load in load case I 2.6.1.1

SMmax II N Maximum type M load in load case II 2.6.2.1

SMmax III N Maximum type M load in load case III 2.6.3.1

SMA N Load due to acceleration or braking 2.5.1

SMCmax N Load due to maximum motor torque 2.6.4.3

SMF N Load due to frictional forces 2.5.1

SMG N Load due to vertical displacement of moveable parts of a liftingappliance. excluding the working load 2.5.1

SML N Load due to vertical displacement of the working load 2.5.1

SMW N Load due to the effect of limiting wind for appliance in service2.5.1

SMW 8 N Load due to wind effect for q - 80 N/mm2 2.6.2.1

SMW 25 N Load due to wind effect for q - 250 N/m2 2.6.2.1

SR N Load due to forces not reacted by torques 2.5



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SRmax I N Maximum type R load in loading case I 2.6.1.1

SRmax II N Maximum type R load in loading case II 2.6.2.1

SRmax III N Maximum type R load in loading case III 2.6.3.1

SRmin N Minimum type R load in bearing calculation 4.2.1.3

SRmoy N Mean type R load in bearing calculation 4.2.1.3

SRA N Load due to accelerations/decelerations 2.5.2

SRG N Load due to self weight of crane parts 2.5.2

SRL N Load due to working load 2.5.2

SRW N Load due to wind 2.5.2

SRWmax N Load due to out of service wind 2.5.2

SRW25 N Wind load for q - 250 N/m2 2.6.2.2

ST N Load due to buffer effect 2.3.3

SV N Variable load when calculating structural members subject to largedeformations 3.5

SW N Load due to in service wind 2.3.2

SWmax N Load due to out of service wind 2.3.3

Sb mm2 Root sectional area of bolt 3.2.2.2.1

Seq mm2 Equivalent sectional area of tightened bolt 3.2.2.2.1

Sp mm2 Area of members of lattice girders and towers 2.2.4.1.4.4

s m Span of lifting appliance :Rail centres of crab :Distance between travel rails of lifting appliance

8.2.2.18.2.2.48.2.3

T h Total duration of use of lifting appliance 2.1.3.3

T J Total kinetic energy in luffing motion A-2.2.3.-4

T °C Ambient temperature at place of erection 3.1.1.3

T N Force parallel to joint plane in bolted joint3.2.2.2.2

T s Duration of cycle 5.8.1.4

T0 à T9 - Classes of utilization of mechanisms 2.1.3.2



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T1 s Period of oscillation A-2.2.3.-2

Ta N Permissible load per bolt which can be transmitted by friction3.2.2.2.2

Tc °C Test temperature for impact test 3.1.3

Ti h Total duration of use of mechanism A-2.1.1

Tm s Mean duration of acceleration or deceleration A-2.2.3-2

t s Time when calculating loads due to horizontal motionA-2.2.3.-2.1

t mm Thickness of structural member when choosing steel quality :Thickness of cylindrical shell wall in buckling analysis :Thickness of web of trolley rail girder

3.1.1.2

A-3.48.2.2.7

t1, t2...ti, tr

s Duration of different levers of loading 2.1.3.3

t1, t2, t3 s Duration of action of couples M1, M2 and M3 5.8.1.3.1

t* mm Ideal section thickness when choosing steel quality 3.1.1.2

td s Duration of deceleration when calculating loads due to horizontalmotion 2.2

tmc s Average duration of a hoisting cycle A-2.1.1

U0 à U9 - Classes of utilization of lifting appliances 2.1.2.2

∆∆∆∆u V Permissible voltage drop 5.3.2

VL m/s Hoisting speed : 2.2.2.1.15.8.2 .1

Vs m/s Theoretical wind speed 2.2.4.1.1

Vt m/s Nominal travel speed of appliance 2.2.3.4.1

v m/s Steady horizontal speed of point of suspension of load A-2.2.3.-2

v mm Distance of extreme fibre from centre of gravity of section incrippling calculation A-3.3

v m/s Travel speed 5.8.3.1

W0, W1, W2 - Notch cases of unwelded members A-3.6

Wi s-1 Angular velocity of a mechanism part about its centre of rotationwhen calculating loads dueto horizontal motion A-2.2.3



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x Ω/km Reactance per unit length 5.3.2

x m Coordinate of point of suspension of hoist rope along an axisparallel to the direction of travel 2.1

x1 m Coordinate of position of centre of gravity of suspended load alongan axis having the same direction. sense and origin as the axis ofx 2.1

ZA - Assessing coefficient for influence A 3.1.1.1

ZB - Assessing coefficient for influence B 3.1.1.2

ZC - Assessing coefficient for influence C 3.1.1.3

Zp - Minimum practical factor of safety for choice of steel wire ropes4.2.2.1

z m Coordinate expressing horizontal displacement of load relative tocrane A-2.2.3.-2.1

zd m Displacement of load during travel motion of craneA-2.2.3.-2.2

zm m Displacement of load during travel motion of craneA-2.2.3.-2.2

αααα - Ratio of sides of panel in buckling calculation T.A-3.4.1

ααααi - Ratio of duration of use of mechanism during a hoisting cycle toaverage duration of cycle A-2.1.1

ααααm ° Angle of inclination of rope during acceleration of craneA-2.2.3.-2.1

ββββ - Time coefficient relating to acceleration of craneA-2.2.3

ββββcrit - Critical value of β A-2.2.3.-2.2

γγγγc - Amplifying coefficient of loading depending on crane group2.3

γγγγm - Amplifying coefficient of loading depending on mechanism group2.6

∆∆∆∆l1 mm Shortening of joined elements under the tightening force in boltedjoints 3.2.2.2.1

∆∆∆∆l2 mm Extension of bolt under tightening force 3.2.2.2.1

∆∆∆∆s mm Divergence in span of crane :Divergence in crane rail centres

8.2.2.18.2.3

δδδδb - Elastic coefficient of bolted joints 3.2.2.2.1

ηηηη - Shielding coefficient in calculation of wind force :Poisson's ratio :Overall efficiency of mechanism

2.2.4.1.4.2A-3.45.8.3.1



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θθθθ ° Angle of wind relative to longitudinal axis of member 2.2.4.1.4.4

κκκκ, κκκκ’, κκκκ’’ - Safety coefficients applying to bolted joints 3.2.2.2.1

κκκκ - Ratio of the extreme stress values in fatigue calculation3.6

κκκκ m/Ωmm2Electric conductivity 5.2.3.3.2

κκκκx, κκκκy, κκκκxy - Ratio of extreme individual stresses σx, σy , τxy in fatiguecalculation A-3.6

λλλλ - Coefficient applied to horizontal forces in travel motions :Slenderness of column in crippling calculation

2.2.3.3A-3.3

µµµµ - Mass constant in calculation of loads due to acceleration ofhorizontal motion :Coefficient of friction in threads :Coefficient of friction of contact surfaces in bolted joints

A-2.2.3.-23.2.2.2.13.2.2.2.2.-3

νννν - Safety coefficient for critical stresses in structural members 3.Intro]

νννν‘ - Dead weight coefficient in calculation of structural memberssubjected to significant deformation 3.5

ννννE - Safety coefficient for calculation of structural members dependingon case of loading 3.2.1.1

ννννR - Safety coefficient for calculation of mechanism parts depending oncase of loading 4.1.1.1

ννννT - = νE , safety coefficient for calculation of bolted joints depending oncase of loading 3.2.2.2.2

ννννV - Safety coefficient for buckling 3.4

ννννK - Safety coefficient for verification of fatigue strength of mechanismparts 4.1.3.7

ξξξξ - Experimentally determined coefficient depending on crane type forcalculating dynamic coefficient 2.2.2.1.1

ρρρρ - Reducing coefficient applied to critical stresses in bucklingcalculation A-3.4

ρρρρ1 - Coefficient used to determine the dynamic test load 2.3.3

ρρρρ2 - Coefficient used to determine the static test load 2.3.3

σσσσ N/mm2 Calculated stress in structures in general 3.2.1.1

σσσσ0 N/mm2 Tensile stress for κ =0 in calculation of fatigue strengthA-3.6



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σσσσ1 N/mm2 Working stress in the root section of bolts 3.2.2.1

σσσσ‘1 N/mm2 Equivalent stresses permissible for bolts 3.2.2.1

σσσσ+1 N/mm2 Permissible tensile stress for κ =+1 in fatigue calculationA-3.6

σσσσA N/mm2 Amplitude of the permissible maximum stress in bolts for fatiguecalculations 3.2.2.1

σσσσE N/mm2 Apparent elastic limit of steel 3.2.2.1

σσσσG N/mm2 Tensile stress due to permanent load :Stress due to dead weight

3.1.1.13.5

σσσσR N/mm2 Ultimate tensile strength 3.2.2.1

σσσσER N/mm2 The EULER Stress A-3.4

σσσσV N/mm2 Stress due to variable loads 3.5

σσσσa N/mm2 Permissible tensile stress for structural members :Permissible stress for mechanism parts

3.1.1.14.1.1.1

σσσσaf N/mm2 Permissible normal stress for verification of fatigue strength ofmechanism parts 4.1.3.7

σσσσb N/mm2 Initial stress in calculating bolted joints 3.2.2.2.1

σσσσbw N/mm2 Endurance limit of materials of mechanism parts under alternatingbending 4.1.3.2

σσσσc N/mm2 Permissible fatigue strength in compression for structural members:Calculated compressive stress for mechanism parts

A-3.64.1.1.3

σσσσcg N/mm2 Compression stress in wheel and rail 4.2.4.2

σσσσcp N/mm2 Equivalent stress used in calculating structural members 3.2.1.3

σσσσcr N/mm2 Critical stress used in calculating structural members subjected tolarge deformations 3.5

σσσσvcr N/mm2 Critical buckling stress A-3.4

σσσσvcr.c N/mm2 Critical comparison stress used in buckling calculation A-3.4

σσσσd N/mm2 Endurance limit of materials of mechanism parts 4.1.3.4

σσσσf N/mm2 Calculated bending stress in mechanism parts 4.1.1.3

σσσσvi N/mm2 Ideal buckling stress for thin walled circular cylinders A-3.4



1 - 18

σσσσinf N/mm2 Lower stress in determination of stress spectrum 2.1.4.3

σσσσk N/mm2 Fatigue strength of mechanism parts 4.1.3.6

σσσσkx N/mm2 Fatigue strength for normal stresses in the x direction 4.1.3.7

σσσσky N/mm2 Fatigue strength for normal stresses in the y direction 4.1.3.7

σσσσm N/mm2 Arithmetic mean of all upper and lower stresses during the totalduration of use :Permissible stress in conformity tests to ISO 3600/1

2.1.4.33.2.2.2.1

σσσσmax N/mm2 Maximum stress in fatigue calculation for structural members 3.6

σσσσmin N/mm2 Minimum stress in fatigue calculation for structural members 3.6.4

σσσσn N/mm2 Bearing pressure in riveted joints 3.2.2.1

σσσσp N/mm2 Theoretical tensile stress in bolt due to tightening 3.2.2.2.1

σσσσsup N/mm2 Upper stress in determination of stress spectrum 2.1.4.3

σσσσsup max N/mm2 Maximum upper stress in determination fo stress spectrum 2.1.4.3

σσσσsup min N/mm2 Minimum upper stress in determination of stress spectrum 2.1.4.3

σσσσt N/mm2 Permissible tensile stress in fatigue verification of structuralmembers :Calculated tensile stress in mechanism parts :Tensile stress in rope

A-3.64.1.1.3A-4.2.2

σσσσv N/mm2 Reduced buckling stress of thin walled circular cylinders A-3.4

σσσσw N/mm2 Permissible stress in alternating tension/compression in fatigueverification of mechanism parts A-3.6

σσσσwk N/mm2 Permissible alternating stress in fatigue verification of mechanismparts 4.1.1.3

σσσσx N/mm2 Normal stress in the x direction when calculating structuralmembers 3.2.1.3

σσσσxa N/mm2 Permissible stress in fatigue verification of structural members A-3.6

σσσσx max N/mm2 Maximum stress in fatigue verification of structural members A-3.6

σσσσx min N/mm2 Minimum stress in fatigue verification of structural members A-3.6

σσσσy N/mm2 Normal stress in the y direction when calculating structuralmembers 3.2.1.3

σσσσya N/mm2 Permissible stress in fatigue verification of structural members A-3.6



1 - 19

σσσσy max N/mm2 Maximum stress in fatigue verification of structural membersA-3.6

σσσσy min N/mm2 Minimum stress in fatigue verification of structural members A-3.6

ττττ N/mm2 Shear stress in general :Calculated shear stress for mechanism parts

3.2.1.34.1.1.3

ττττa N/mm2 Permissible shear stress when calculating structural members 3.2.1.2

ττττaf N/mm2 Permissible shear stress in fatigue verification of mechanism parts 4.1.3.7

ττττb N/mm2 Torsional stress in bolts due to tightening 3.2.2.2.1

ττττvcr N/mm2 Critical buckling shear stress A-3.4

ττττd N/mm2 Endurance limit of materials of mechanism parts 4.1.3.4

ττττk N/mm2 Fatigue strength of mechanism parts 4.1.3.6

ττττmax N/mm2 Maximum shear stress in fatigue verification of mechanism parts 3.6.4

ττττmin N/mm2 Minimum shear stress in fatigue verification of mechanism parts 3.6.4

ττττw N/mm2 Endurance limit under alternating shear of materials of mechanismparts 4.1.3.2

ττττwk N/mm2 Endurance limit under alternating shear in fatigue verification ofmechanism parts 4.1.3.3

ττττxy N/mm2 Shear stress when calculating structural members 3.2.1.3

ττττxya N/mm2 Permissible shear stress in fatigue verification of structuralmembers A-3.6

ττττxy max N/mm2 Maximum shear stress in fatigue verification of structural members A-3.6

ττττxy min N/mm2 Minimum shear stress in fatigue verification of structural members A-3.6

ϕϕϕϕ, ϕϕϕϕ‘ - Slope of Wöhler curve 4.1.3.5

ψψψψ - Dynamic coefficient for hoist motion :Ratio of stresses at plate edges in buckling calculation

2.2 .2.1.13.4

ψψψψh - Dynamic coefficient when calculating loads due to acceleration ofhorizontal motions A-2.2.3.-2

ΩΩΩΩ - Tolerance factor in bolted joints 3.2.2.2.1

ωωωω - Crippling coefficient 3.3

ωωωω s-1 Angular velocity of shaft when calculating loads due to horizontal



1 - 20

motion A-2.2.3.-3

ωωωω1, ωωωω2, ωωωωr s-1 Frequencies of oscillation during load swing A-2.2.3.-2.2

ωωωωm s-1 Angular velocity of motor A-2.2.3.-2.1




SECTION I


F.E.M.

1.001 3rd EDITION

REVISED

1998.10.01


HOISTING APPLIANCES

B O O K L E T 2

CLASSIFICATION AND LOADING ON STRUCTURES AND MECHANISMS





Booklet 2

CLASSIFICATION AND LOADING

ON STRUCTURES AND MECHANISMS

2.1 GROUP CLASSIFICATION OF HOISTING APPLIANCES AND THEIR COMPONENT PARTS.......................................................................................................................................................................4

2.1.1. GENERAL PLAN OF CLASSIFICATION .................................................................................4

2.1.2. CLASSIFICATION OF HOISTING APPLIANCES AS A WHOLE..........................................42.1.2.1. CLASSIFICATION SYSTEM ...................................................................................................... 42.1.2.2. CLASSES OF UTILIZATION...................................................................................................... 42.1.2.3. LOAD SPECTRUM .................................................................................................................... 52.1.2.4. GROUP CLASSIFICATION OF HOISTING APPLIANCES............................................................ 72.1.2.5. GUIDANCE ON GROUP CLASSIFICATION OF AN APPLIANCE................................................. 7

2.1.3. CLASSIFICATION OF INDIVIDUAL MECHANISMS AS A WHOLE .....................................72.1.3.1. CLASSIFICATION SYSTEM ...................................................................................................... 72.1.3.2. CLASSES OF UTILIZATION...................................................................................................... 92.1.3.3. LOADING SPECTRUM............................................................................................................... 92.1.3.4. GROUP CLASSIFICATION OF INDIVIDUAL MECHANISMS AS A WHOLE............................... 102.1.3.5. GUIDANCE FOR GROUP CLASSIFICATION OF INDIVIDUAL MECHANISMS AS A WHOLE .... 10

2.1.4. CLASSIFICATION OF COMPONENTS .................................................................................122.1.4.1. CLASSIFICATION SYSTEM .................................................................................................... 122.1.4.2. CLASSES OF UTILIZATION.................................................................................................... 122.1.4.3. STRESS SPECTRUM............................................................................................................... 132.1.4.4. GROUP CLASSIFICATION OF COMPONENTS ........................................................................ 14



2 - 2

2.2. LOADS ENTERING INTO THE DESIGN OF STRUCTURES ..........................................................15

2.2.1. PRINCIPAL LOADS...................................................................................................................15

2.2.2. LOADS DUE TO VERTICAL MOTIONS..................................................................................162.2.2.1. LOADS DUE TO HOISTING OF THE WORKING LOAD............................................................. 16

2.2.2.1.1. VALUES OF THE DYNAMIC COEFFICIENT ψ ................................................................... 162.2.2.2. LOADS DUE TO ACCELERATION (OR DECELERATION) OF THE HOISTING MOTION AND TOVERTICAL SHOCK LOADINGS WHEN TRAVELLING ALONG RAIL TRACKS ...................................... 172.2.2.3. SPECIAL CASE........................................................................................................................ 17

2.2.3. LOADS DUE TO HORIZONTAL MOTIONS SH......................................................................192.2.3.1. HORIZONTAL EFFECTS DUE TO ACCELERATION (OR DECELERATION)........................ 19

2.2.3.1.1. TRAVERSE AND TRAVEL MOTIONS................................................................................ 192.2.3.1.2. SLEWING AND LUFFING (DERRICKING) MOTIONS ......................................................... 20

2.2.3.2. EFFECTS OF CENTRIFUGAL FORCE....................................................................................... 202.2.3.3. TRANSVERSE REACTIONS DUE TO ROLLING ACTION.......................................................... 212.2.3.4. BUFFER EFFECTS ST............................................................................................................... 21

2.2.3.4.1. BUFFER EFFECTS ON THE STRUCTURE ........................................................................ 212.2.3.4.2. BUFFER EFFECTS ON THE SUSPENDED LOAD ............................................................. 22

2.2.4. LOADS DUE TO CLIMATIC EFFECTS...................................................................................222.2.4.1 WIND ACTION........................................................................................................................... 22

2.2.4.1.1. WIND PRESSURE......................................................................................................... 222.2.4.1.2. DESIGN WIND CONDITIONS ............................................................................................ 23

2.2.4.1.2.1. In-service wind ................................................................................................................ 232.2.4.1.2.2. Wind out of service .......................................................................................................... 24

2.2.4.1.3. WIND LOAD CALCULATIONS........................................................................................... 252.2.4.1.4. SHAPE COEFFICIENTS.................................................................................................... 25

2.2.4.1.4.1. Individual members, frames, etc. ........................................................................................ 252.2.4.1.4.2. Multiple frames of members : shielding factors...................................................................... 282.2.4.1.4.3. Lattice towers.................................................................................................................. 292.2.4.1.4.4. Parts inclined in relation to the wind direction ....................................................................... 29

2.2.4.2. SNOW LOAD........................................................................................................................... 302.2.4.3. TEMPERATURE VARIATIONS.................................................................................................. 30

2.2.5 MISCELLANEOUS LOADS.......................................................................................................302.2.5.1. LOADS CARRIED BY PLATFORMS......................................................................................... 30

2.3. CASES OF LOADING ........................................................................................................................31

2.3.1. CASE I : APPLIANCE WORKING WITHOUT WIND.............................................................31

2.3.2. CASE II : APPLIANCE WORKING WITH WIND ....................................................................31

2.3.3. CASE III : APPLIANCE SUBJECTED TO EXCEPTIONAL LOADINGS .............................32

2.3.4. CHOOSING THE AMPLIFYING COEFFICIENT γC ...............................................................33

2.4. SEISMIC EFFECTS ............................................................................................................................33

2.5. LOADS ENTERING INTO THE DESIGN OF MECHANISMS..........................................................34

2.5.1. TYPE SM LOADS........................................................................................................................34

2.5.2. TYPE SR LOADS........................................................................................................................34



2 - 3

2.6. CASES OF LOADING ........................................................................................................................35

2.6.1. CASE I - NORMAL SERVICE WITHOUT WIND....................................................................352.6.1.1. TYPE SM LOADS..................................................................................................................... 352.6.1.2. TYPE SR LOADS ..................................................................................................................... 35

2.6.2. CASE II - NORMAL SERVICE WITH WIND ...........................................................................362.6.2.1. TYPE SM LOADS..................................................................................................................... 362.6.2.2. TYPE SR LOADS ..................................................................................................................... 36

2.6.3. CASE III - EXCEPTIONAL LOADS ..........................................................................................372.6.3.1. TYPE SM LOADS..................................................................................................................... 372.6.3.2. TYPE SR LOADS ..................................................................................................................... 37

2.6.4. APPLICATION OF THE ABOVE CONSIDERATIONS FOR CALCULATING SM ..............372.6.4.1. HOISTING MOTIONS................................................................................................................ 382.6.4.2. HORIZONTAL MOTIONS.......................................................................................................... 382.6.4.3. COMBINED MOTIONS .............................................................................................................. 39

.....................................................................................................................................................................39

APPENDIX..................................................................................................................................................40

A.2.1.1. - HARMONISATION OF THE CLASSES OF UTILIZATION OF APPLIANCES ANDMECHANISMS.......................................................................................................................................40

A.2.2.3. - CALCULATION OF LOADS DUE TO ACCELERATIONS OF HORIZONTAL MOTIONS.................................................................................................................................................................45



2 - 4

2.1 GROUP CLASSIFICATION OF HOISTING APPLIANCESAND THEIR COMPONENT PARTS

2.1.1. GENERAL PLAN OF CLASSIFICATION

In the design of a hoisting appliance and its component parts, account must be taken of the dutywhich they will be required to perform during their duration of use ; for this purpose groupclassification is employed of :

- the appliance as a whole ;

- the individual mechanisms as a whole ;

- the structural and mechanical components.

This classification is based on two criteria, namely :

- the total duration of use of the item considered ;

- the hook load, loading or stress spectra to which the item is subjected.

2.1.2. CLASSIFICATION OF HOISTING APPLIANCES AS A WHOLE

2.1.2.1. CLASSIFICATION SYSTEM

Appliances as a whole are classified in eight groups, designated by the symbol A1, A2, ..., A8respectively (see section 2.1.2.4.), on the basis of ten classes of utilization and four load spectra.

2.1.2.2. CLASSES OF UTILIZATION

By duration of use of a hoisting appliance is meant the number of hoisting cycles which theappliance performs. A hoisting cycle is the entire sequence of operations commencing when aload is hoisted and ending at the moment when the appliance is ready to hoist the next load.

The total duration of use is a computed duration of use, considered as a guide value,commencing when the appliance is put into service and ending when it is finally taken out ofservice.

On the basis of the total duration of use, we have ten classes of utilization, designated by thesymbol U0, U1, ..., U9. They are defined in table T.2.1.2.2.



2 - 5

Table T.2.1.2.2. - Classes of utilization

SymbolTotal duration of use

(number nmax of hoisting cycles)U0U1U2U3U4U5U6U7U8U9

16 00032 00063 000

125 000250 000500 000

1 000 0002 000 0004 000 000

<<<<<<<<<

nmax

nmax

nmax

nmax

nmax

nmax

nmax

nmax

nmax

nmax

≤≤≤≤≤≤≤≤≤

16 00032 00063 000125 000250 000500 000

1 000 0002 000 0004 000 000

2.1.2.3. LOAD SPECTRUM

The load spectrum characterises the total number of loads hoisted during the total duration ofuse (see 2.1.2.2.) of an appliance. It is a distribution function (summed) y = f(x), expressing thefraction x (O ≤ x ≤ 1) of the total duration of use, during which the ratio of the hoisted load to thesafe working load attains at least a given value y (O ≤ y ≤ 1).

Examples of a load spectrum are given in figs. 2.1.2.3.1. - a and b.

Figure 2.1.2.3.1. - a Figure 2.1.2.3.1. - b

ml = loads ; ml max = safe working load ;n = number of hoisting cycles in respect of which the hoisted load is greaterthan or equal to ml;nmax = number of hoisting cycles determining the total duration of use.Each spectrum is assigned a spectrum factor kp, defined by :

KP =0

1

∫ yd dx



2 - 6

For the purposes of group classification the exponent d is taken by convention as equal to 3.

In many applications the function f(x) may be approximated by a function consisting of a certainnumber r of steps (see fig. 2.1.2.3.2.), comprising respectively n1, n2, ..., nr hoisting cycles, theload may be considered as practically constant and equal to mli during the ni cycles of the ith step.If nmax represents the total duration of use and ml max the greatest among the mli loads, thereexists a relation :

n1 + n2 + ..... + nr = i

r

=∑

1

ni = nmax

or in approximated form :

kp = ( ml1/mlmax)3.(n1/nmax) + ( ml2/mlmax)

3.(n2/nmax) + .....+ ( mlr/mlmax)3.(nr/nmax)

kp = i

r

=∑

1

[ ( mli/mlmax)3.(ni/nmax) ]

Figure 2.1.2.3.2.

According to its load spectrum, a hoisting appliance is placed in one of the four spectrumclasses Q1, Q2, Q3, Q4 defined in table T.2.1.2.3.

Table T.2.1.2.3. - Spectrum classes

Symbol Spectrum factor kp

Q1Q2Q3Q4

kp ≤ 0,1250,125 < kp ≤ 0,2500,250 < kp ≤ 0,5000,500 < kp ≤ 1,000



2 - 7

2.1.2.4. GROUP CLASSIFICATION OF HOISTING APPLIANCES

Group classification of hoisting appliances as a whole is determined from table T.2.1.2.4.

Table T.2.1.2.4. - Appliance groups

Load Class of utilizationspectrum

class U0 U1 U2 U3 U4 U5 U6 U7 U8 U9Q1Q2Q3Q4

A1A1A1A2

A1A1A2A3

A1A2A3A4

A2A3A4A5

A3A4A5A6

A4A5A6A7

A5A6A7A8

A6A7A8A8

A7A8A8A8

A8A8A8A8

2.1.2.5. GUIDANCE ON GROUP CLASSIFICATION OF AN APPLIANCE

Directions concerning the classification of hoisting appliances are given in table T.2.1.2.5.

Since appliances of the same type may be used in a wide variety of ways, the grouping shown inthis table can only be taken as a model. In particular, where several groups are shown asappropriate to an appliance of a given type, it is necessary to ascertain, on the basis of theappliance's computed total duration of use and load spectrum, in which classes of utilization andload spectrum it has to be placed, and consequently in which group.

2.1.3. CLASSIFICATION OF INDIVIDUAL MECHANISMS AS A WHOLE


Individual mechanisms as a whole are classified in eight groups, designated respectively by thesymbol M1, M2, ..., M8 (see 2.1.3.4.), on the basis of ten classes of utilization and four classes ofloading spectrum.



2 - 8

Table T.2.1.2.5. - Guidance for group classification of appliances

Type of appliance Particulars concerning ApplianceRefe-rence Designation

nature of use(1)

group(see 2.1.2.4.)

1 Hand-operated appliances A1 - A22 Erection cranes A1 - A23 Erection and dismantling cranes for power

stations, machine shops, etc. A2 - A44 Stocking and reclaiming transporters Hook duty A5

5Stocking and reclaiming transporters Grab or magnet

A6 - A86 Workshop cranes A3 - A57 Overhead travelling cranes, pigbreaking

cranes, scrapyard cranesGrab or magnet

A6 - A88 Ladle cranes A6 - A89 Soaking-pit cranes A8

10 Stripper cranes, open-hearth furnace-charging cranes

A8

11 Forge cranes A6 - A812.a

12.b

Bridge cranes for unloading, bridge cranesfor containersOther bridge cranes (with crab and/orslewing jib crane)

Hook or spreader duty

Hook duty

A5 - A6

A413 Bridge cranes for unloading, bridge cranes

(with crab and/or slewing jib crane)Grab or magnet

A6 - A814 Drydock cranes, shipyard jib cranes, jib

cranes for dismantling Hook duty A3 - A515 Dockside cranes (slewing, on gantry),

floating cranes and pontoon derricks Hook duty A5 - A616 Dockside cranes (slewing, on gantry),

floating cranes and pontoon derricksGrab or magnet

A6 - A817 Floating cranes and pontoon derricks for

very heavy loads (usually greater than 100t) A2 - A3

18 Deck cranes Hook duty A3 - A4

19Deck cranes Grab or magnet

A4 - A520 Tower cranes for building A3 - A421 Derricks A2 - A322 Railway cranes allowed to run in train

A4

(1) Only a few typical cases of use are shown, by way of guidance, in this column.



2 - 9


By duration of use of a mechanism is meant the time during which the mechanism is actually inmotion.

The total duration of use is a calculated duration of use, considered as a guide value, applyingup to the time of replacement of the mechanism. It is expressed in terms of hours.

On the basis of this total duration of use, we have ten classes of utilization, TO, T1, T2, ..., T9.They are defined in table T.2.1.3.2.


Symbol Total duration of use T (h)T0T1T2T3T4T5T6T7T8T9

T ≤ 200200 < T ≤ 400400 < T ≤ 800800 < T ≤ 1600

1 600 < T ≤ 32003 200 < T ≤ 63006 300 < T ≤ 12 500

12 500 < T ≤ 25 00025 000 < T ≤ 50 00050 000 < T

2.1.3.3. LOADING SPECTRUM

The loading spectrum characterizes the magnitude of the loads acting on a mechanism duringits total duration of use. It is a distribution function (summed) y = f(x), expressing the fraction x (0≤ x ≤ 1) of the total duration of use, during which the mechanism is subjected to a loadingattaining at least a fraction y (0 ≤ y ≤ 1) of the maximum loading (see figure 2.1.2.3.1.).

Each spectrum is assigned a spectrum factor km defined by :

km =0

1

∫ yd dx

For the purposes of group classification, d is taken by convention as equal to 3.

In many applications the function f(x) may be approximated by a function consisting of a certainnumber r of steps (see fig. 2.1.2.3.2.), of respective durations tl, t2, ..., tr, the loadings S may beconsidered as practically constant and equal to Si during the duration ti. If T represents the totalduration of use and Smax the greatest of the loadings S1, S2, ..., Sr, there exists a relation :

t1 + t2 + ... + tr = i

r

=∑

1

ti = T



2 - 10

and in approximated form :

km = (S1/Smax)3 ( t1/T) + (S2/Smax)

3 ( t2/T) + ..... +(Sr/Smax)3 ( tr/T) =

i

r

=∑

1

[ (Si/Smax)3 ( ti/T) ]

Depending on its loading spectrum, a mechanism is placed in one of the four spectrum classesL1, L2, L3, L4, defined in table T.2.1.3.3.


Symbol Spectrum factor km

L1L2L3L4

km ≤ 0,1250,125 < km ≤ 0,2500,250 < km ≤ 0,5000,500 < km ≤ 1,000

2.1.3.4. GROUP CLASSIFICATION OF INDIVIDUAL MECHANISMS AS A WHOLE

On the basis of their class of utilization and their spectrum class, individual mechanisms as awhole are classified in one of the eight groups M1, M2, ..., M8, defined in table T.2.1.3.4.

Table T.2.1.3.4. - Mechanism groups

Class of Class of utilizationload

spectrum T0 T1 T2 T3 T4 T5 T6 T7 T8 T9L1L2L3L4

M1M1M1M2

M1M1M2M3

M1M2M3M4

M2M3M4M5

M3M4M5M6

M4M5M6M7

M5M6M7M8

M6M7M8M8

M7M8M8M8

M8M8M8M8

2.1.3.5. GUIDANCE FOR GROUP CLASSIFICATION OF INDIVIDUAL MECHANISMS AS A WHOLE

Guidance for group classification of an individual mechanism as a whole is given in tableT.2.1.3.5.

Since appliances of the same type may be used in a wide variety of ways, the grouping directionsin this table can only be taken as a model. In particular, where several groups are shown asappropriate to a mechanism of a given type, it is necessary to ascertain, on the basis of themechanism's calculated total duration of use and loading spectrum, in which class of utilization(see 2.1.3.2.) and spectrum (see 2.1.3.3.) it has to be placed, and consequently in which groupof mechanisms (see 2.1.3.4.).



2 - 11

Table T.2.1.3.5. - Guidance for group classification of a mechanism

Type of appliance Particulars Type of mechanismRefe-rence Designation

concerningnature of use (1)

Hoisting Sle-wing

Luffing Traver-se

Travel

1 Hand-operated appliances M1 - - M1 M12 Erection cranes M2-M3 M2-M3 M1-M2 M1-M3 M2-M33 Erection and dismantling cranes for

power stations, machine shops, etc. M2 - - M2 M24 Stocking and reclaiming transporters Hook duty

M5-M6 M4 - M4-M5 M5-M65 Stocking and reclaiming transporters Grab or magnet

M7-M8 M6 - M6-M7 M7-M86 Workshop cranes M6 M4 - M4 M57 Overhead travelling cranes,

pigbreaking cranes, scrapyardcranes

Grab or magnetM8 M6 - M6-M7

M7-M8

8 Ladle cranes M7-M8 - - M4-M5 M6-M79 Soaking-pit cranes M8 M6 - M7 M8

10 Stripper cranes, open-hearthfurnace-charging cranes M8 M6

-M7 M8

11 Forge cranes M8 -- - M5 M612-a

12-b

Bridge cranes for unloading, bridgecranes for containersOther bridge cranes (with craband/or slewing jib crane)

a - Hook orspreader duty

b - Hook duty

M6-M7

M4-M5

M5-M6

M4-M5

M3-M4

-

M6-M7

M4-M5

M4-M5

M4-M513 Bridge cranes for unloading, bridge

cranes (with crab and/or slewing jibcrane)

Grab or magnetM8 M5-M6 M3-M4 M7-M8 M4-M5

14 Drydock cranes, shipyard jib cranes,jib cranes for dismantling

Hook dutyM5-M6 M4-M5 M4-M5 M4-M5 M5-M6

15 Dockside cranes (slewing, on gantry,etc.), floating cranes and pontoonderricks

Hook dutyM6-M7 M5-M6 M5-M6 - M3-M4

16 Dockside cranes (slewing, on gantry,etc.), floating cranes and pontoonderricks

Grab or magnetM7-M8 M6-M7 M6-M7 - M4-M5

17 Floating cranes and pontoonderricks for very heavy loads (usuallygreater than 100 t)

M3-M4 M3-M4 M3-M4 - -

18 Deck cranes Hook duty M4 M3-M4 M3-M4 M2 M319 Deck cranes Grab or magnet

M5-M6 M3-M4 M3-M4 M4-M5 M3-M420 Tower cranes for building M4 M5 M4 M3 M321 Derricks M2-M3 M1-M2 M1-M2 - -22 Railway cranes allowed to run in

train M3-M4 M2-M3 M2-M3 - -

(1) Only a few typical cases of use are shown, by way of guidance, in this column.



2 - 12

2.1.4. CLASSIFICATION OF COMPONENTS


Components, both structural and mechanical, are classified in eight groups, designedrespectively by the symbol E1, E2, ..., E8, on the basis of eleven classes of utilization and fourclasses of stress spectrum.


By duration of use of a component is meant the number of stress cycles to which the componentis subjected.A stress cycle is a complete set of successive stresses, commencing at the moment when thestress under consideration exceeds the stress σm defined in fig. 2.1.4.3. and ending at the

moment when this stress is, for the first time, about to exceed again σm in the same direction.

Fig. 2.1.4.3. therefore represents the trend of the stress σ over a duration of use equal to fivestress cycles.The total duration of use is a computed duration of use, considered as a guide value, applyingup to the time of replacement of the component.In the case of structural components the number of stress cycles is in a constant ratio with thenumber of hoisting cycles of the appliance. Certain components may be subjected to severalstress cycles during a hoisting cycle depending on their position in the structure. Hence the ratioin question may differ from one component to another. Once this ratio is known, the total durationof use of the component is derived from the total duration of use which determined the class ofutilization of the appliance.As regards mechanical components, the total duration of use is derived from the total duration ofuse of the mechanism to which the component under consideration belongs, account beingtaken of its speed of rotation and/or other circumstances affecting its operation.On the basis of the total duration of use, we have eleven classes of utilization, designatedrespectively by the symbol BO, B1, ..., B10. They are defined in table T.2.1.4.2.


SymbolTotal duration of use

(number n of stress cycles)B0B1B2B3B4B5B6B7B8B9B10

n ≤ 16 00016 000 < n ≤ 32 00032 000 < n ≤ 63 00063 000 < n ≤ 125 000

125 000 < n ≤ 250 000250 000 < n ≤ 500 000500 000 < n ≤ 1 000 000

1 000 000 < n ≤ 2 000 0002 000 000 < n ≤ 4 000 0004 000 000 < n ≤ 8 000 0008 000 000 < n



2 - 13

2.1.4.3. STRESS SPECTRUM

The stress spectrum characterizes the magnitude of the load acting on the component during itstotal duration of use. It is a distribution function (summed) y = f(x), expressing the fraction x (O ≤ x≤ 1) of the total duration of use (see 2.1.4.2.), during which the component is subjected to astress attaining at least a fraction y (O ≤ x ≤ 1) of the maximum stress.

Each stress spectrum is assigned a spectrum factor ksp, definedby

ksp = 0

1

∫ yc dx

Where c is an exponent depending on the properties of the material concerned, the shape andsize of the component in question, its surface roughness and its degree of corrosion (seebooklet 4).

In many applications the function f(x) may be approximated by a function consisting of a certainnumber r of steps, comprising respectively n1, n2, ..., nr stress cycles ; the stress σ may be

considered as practically constant and equal to σi during ni cycles. If n represents the total

duration of use and σmax the greatest of the stresses σ1, σ2, ..., σr there exists a relation :

n1 + n2+ ..... + nr = i

r

=∑

1

ni = n

and in approximated form :

ksp = (σ1/ σmax)c (n1 / n) + (σ2/ σmax)

c (n2 / n) + ..... +(σr/ σmax)c (nr / n) =

i

r

=∑

1

[ (σi/ σmax)c (ni / n) ]

Depending on its stress spectrum, a component is placed in one of the spectrum classes P1,P2, P3, P4, defined in table T.2.1.4.3. 1


Symbol Spectrum factor ksp

P1P2P3P4

ksp ≤ 0,1250,125 < ksp ≤ 0,2500,250 < ksp ≤ 0,5000,500 < ksp ≤ 1,000

1 There are components, both structural and mechanical, such as spring loaded components,which are subjected to loading that is quite or almost independent of the working load. Specialcare shall be taken in classifying such components. In most cases ksp = 1 and they belong toclass P4.



2 - 14

For structural components, the stresses to be taken into consideration for determination of thespectrum factor are the differences σsup - σm between the upper stresses σsup and the average

stress σm, these concepts being defined by fig. 2.1.4.3. representing the variation of the stressover time during five stress cycles.

Fig. 2.1.4.3. - Variation of stress as a function of time during a five stress cycles

σsup = upper stress σsup max = maximum upper stress

σsup min = minimum upper stress σinf = longer stress

σm = arithmetic mean of all upper and lower stresses during the total duration of use

In the case of mechanical components, we can put σm = 0 the stresses to be introduced into thecalculation of the spectrum factor then being the total stresses occurring in the relevant sectionof the component.

2.1.4.4. GROUP CLASSIFICATION OF COMPONENTS

On the basis of their class of utilization and their stress spectrum class, components areclassified in one of the eight groups E1, E2, ..., E8, defined in table T.2.1.4.4.

Table T.2.1.4.4. - Component groups

StressSpectrum

Class of utilization

class B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B10P1P2P3P4

E1E1E1E1

E1E1E1E2

E1E1E2E2

E1E2E3E4

E2E3E4E5

E3E4E5E6

E4E5E6E7

E5E6E7E8

E6E7E8E8

E7E8E8E8

E8E8E8E8



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2.2. LOADS ENTERING INTO THE DESIGN OF STRUCTURES

The structural calculations shall be conducted by determining the stresses developed in anappliance during its operation. These stresses shall be calculated on the basis of the loadsdefined below :

a) The principal loads exerted on the structure of the appliance, assumed to be stationary, inthe most unfavourable state of loading ;

b) Loads due to vertical motions ;

c) Loads due to horizontal motions ;

d) Loads due to climatic effects.

The various loads, the factors to be applied, and the practical method of conducting thecalculations are examined below. In what follows, the definitions given below are used :

Working load : Weight of the useful load lifted, plus the weight of the accessories (sheavesblocks, hooks, lifting beams, grab, etc.).

Dead load : Dead weight of components acting on a given member, excluding the workingload.

2.2.1. PRINCIPAL LOADS

The principal loads include :

- the loads due to the dead weight of the components : SG

- the loads due to the working load : SL

all movable parts being assumed to be in their most unfavourable position.

Each structural member shall be designed for the position of the appliance and magnitude of theworking load (between zero and the safe working load) which gives rise to the maximumstresses 2 in the member in question.

2 (1) In certain cases, the maximum stress may be obtained with no working load.



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2.2.2. LOADS DUE TO VERTICAL MOTIONS

These loads stem from picking up the working load more or less suddenly from accelerations(or decelerations) of the hoisting motion, and from vertical shock loadings due to travelling alongrails tracks.

2.2.2.1. LOADS DUE TO HOISTING OF THE WORKING LOAD

Account shall be taken of the oscillations caused when lifting the load by multiplying the loadsdue to the working load by a factor called the "dynamic coefficient" ψ.

2.2.2.1.1. VALUES OF THE DYNAMIC COEFFICIENT ψψψψ

The value of the dynamic coefficient ψto be applied to the load arising from the working load isgiven by the expression :

ψ = 1 + ξ VL

Where :VL is the hoisting speed in m/s, and ξ an experimentally determined coefficient 3

The following values shall be adopted :ξ = 0,6 for overhead travelling cranes and bridge cranes ξ = 0,3 for jib cranes.

The maximum figure to be taken for the hoisting speed when applying this formula is 1 m/s. Forhigher speeds, the dynamic coefficient ψ is not further increased.

The value to be applied for the coefficient ψ in the calculations shall in no case be less than 1,15.

The values of ψ are given in the curves of figure 2.2.2.1.1. in terms of hoisting speeds VL.

A : Overhead travelling cranes, Bridge cranes B : Jib cranes

Figure 2.2.2.1.1. - Values of dynamic coefficient ψψψψ

3 In certain cases, the maximum stress may be obtained with no working load.



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Note - The above mentioned coefficient ξ is not the same for "overhead travelling cranes andbridge cranes" and for "jib cranes".

The difference arises from the fact that the dynamic coefficient ψ is, other things being equal,smaller when the hoisting load is carried by a member having some flexibility, as in jib craneswhere the jib is never rigid.

In a similar way, use of the coefficient ψ as indicated for jib cranes may be extended to certainother appliances such as, for example, transporters for the design case corresponding to loadon the cantilever boom ; the value of ψ indicated for overhead travelling cranes should, of course,be used for the design cases where the load is applied between the legs of the machine as therigidity of the structure at this point is comparable with that one of an overhead travelling cranegirder.

2.2.2.2. LOADS DUE TO ACCELERATION (OR DECELERATION) OF THE HOISTING MOTION ANDTO VERTICAL SHOCK LOADINGS WHEN TRAVELLING ALONG RAIL TRACKS

Since the coefficient ψ takes account of the degree of snatch on the working load which is thelargest shock loading, loads due to acceleration (or deceleration) of the hoisting motion and thevertical reactions due to travelling along tracks, assumed to be properly laid, shall be neglected 4

2.2.2.3. SPECIAL CASE

In the case of certain appliances, the loads due to the dead loads are of opposite sign to thosedue to the working load, in which case a comparison must be made between the loading figureobtained in the "appliance under load" condition, with the dynamic coefficient ψ applied to theworking load, and the loading figure obtained in the "no-load" condition, taking into account theoscillations resulting from setting clown the load, as follows :Let :

SG be the algebraic value of the loads due to the dead load

SL be the algebraic value of the loads due to the working load.

SG - SL (ψ-1)/2

Which is compared with the load for the "appliance under load" condition determined by theexpression :

4 This assumes that the rail joints are in good condition. The detrimental effect on hoisting appliances of railtracks in poor condition is so great, both for the structure and the machinery, that it is necessary to stipulatethat the rail joints must be maintained in good condition : no shock loading coefficient can allow for thedamage caused by faulty joints. In so far as high speed appliances are concerned, the best solution is tobutt-weld the rails, in order to eliminate entirely the shock loadings which occur when an appliance runs overjoints.The amplified total load, when setting clown the load is obtained by the expression :



2 - 18

SG + ψ SL



2 - 19

the component being finally designed on the basis of the more unfavourable of these two values.

Note - This formula is based on the fact that the dynamic coefficient determines the maximumamplitude of the oscillations set up in the structure when the load is picked up. The amplitude ofthe oscillation is given by :

SL (ψ-1)

It is assumed that the amplitude of the oscillation set up in the structure when the load is setclown is half that of the oscillation caused when hoisting takes place.

The ultimate state of loading is therefore :SG - SL (ψ-1)/2

which must be compared with the state of loading given by :

SG + ψ SL

Hoisting and lowering curve when SL and SG are of opposite sign



2 - 20

2.2.3. LOADS DUE TO HORIZONTAL MOTIONS SH

The loads due to horizontal motions are as follows :

1) The inertia effects due to acceleration (or deceleration) of the traverse, travel, slewing orluffing motions. These effects can be calculated in terms of the value of the acceleration (ordeceleration).

2) The effects of centrifugal force.

3) Transverse horizontal reactions resulting from rolling action.

4) Buffer effects.

2.2.3.1. HORIZONTAL EFFECTS DUE TO ACCELERATION (OR DECELERATION)

The loads due to the accelerations (or decelerations) imparted to the movable elements whenstarting or braking are calculated for the various structural members.

2.2.3.1.1. TRAVERSE AND TRAVEL MOTIONS

For these motions the calculation is made by considering a horizontal force applied at the treadof the driven wheels parallel to the rail.

The loads shall be calculated in terms of the acceleration (or deceleration) time assumedaccording to the working conditions and the speeds to be attained.

From it is deduced the value (in m/s2) of the acceleration to be used for calculating the horizontalforce according to the masses to be set in motion.

Note - If the speed and acceleration values are not specified by the user, acceleration timescorresponding to the speeds to be reached may be chosen according to the three followingworking conditions :

a) Appliances of low and moderate speed with a great length of travel ;

b) Appliances of moderate and high speed for normal applications ;

c) High speed appliances with high acceleration.

In the latter case, it is almost always necessary to drive all the rail wheels.

Table T.2.2.3.1.1. gives the values of acceleration times and accelerations for the threeconditions.



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Table T.2.2.3.1.1. - Acceleration time and acceleration value

Speed

(a)low and moderate speed

with long travel

(b)moderate and high speed

(normal applications)

(c)high speed with high

accelerationsto be reached

m/s

Accelerationtime

s

Acceleration

m/s2

Accelerationtime

s

Acceleration

m/s2

Accelerationtime

s

Acceleration

m/s2

4,003,152,52

1,601,000,630,400,250,16

9,18,36,65,24,13,22,5

0,220,190,150,120,0980,0780,064

8,07,16,35,65,04,03,22,5

0,500,440,390,350,320,250,190,16

6,05,44,84,23,73,0

0,670,580,520,470,430,33

The horizontal force to be taken into account shall be not less than 1/30th nor more than 1/4 ofthe load on the driven or braked wheels.

2.2.3.1.2. SLEWING AND LUFFING (DERRICKING) MOTIONS

For slewing and luffing motions the calculations shall be based on the accelerating (ordecelerating) torque applied to the motor shaft of the mechanisms.

The rates of acceleration will depend upon the appliance ; for a normal crane a value between0.1 m/s2 and 0.6 m/s2, according to the speed and radius, may be chosen for the acceleration atthe jib head so that an acceleration time of from 5 to 10 s is achieved.

Note - A method for calculating the effects of acceleration of horizontal motions is given inappendix A.2.2.3.

2.2.3.2. EFFECTS OF CENTRIFUGAL FORCE

In the case of jib cranes, account shall be taken of the centrifugal force due to slewing. Inpractice, it is sufficient to determine the horizontal force exerted at the jib head as a result of theinclination of the rope carrying the load and in general to neglect the effects of centrifugal force onthe other elements of the crane.



2 - 22

2.2.3.3. TRANSVERSE REACTIONS DUE TO ROLLING ACTION

When two wheels (or two bogies) roll along a rail, the couple formed by the horizontal forcesnormal to the rail shall be taken into consideration. The components of this couple are obtainedby multiplying the vertical load exerted on the wheels (or bogies) by a coefficient λ whichdepends upon the ratio of the span p to the wheel base a 5.

As shown in the graph, this coefficient lies between 0.05 and 0.2 for ratios p/a between 2 and 8.

2.2.3.4. BUFFER EFFECTS ST

The case must be considered when the impact due to collision with buffers is applied to thestructure, and the case when it is applied to the suspended load.

2.2.3.4.1. BUFFER EFFECTS ON THE STRUCTURE

A distinction must be drawn between :

1) the case in which the suspended load can swing.

2) that in which rigid guides prevent swing.

In the first case the following rules shall be applied :

For horizontal speeds below 0.7 m/sec, no account shall be taken of buffer effects.

For speeds in excess of 0.7 m/sec, account must be taken of the reactions set up in thestructure by collisions with buffers.

It shall be assumed that a buffer is capable of absorbing the kinetic energy of the appliance(without the working load) at a fraction of the rated speed Vt fixed at 0.7 Vt.

5 By "wheelbase" is understood the centre distance between the outermost pairs of wheels, or, in the caseof bogies, the centre distance between the fulcrum pins on the crane structure of the two bogies or bogiesystems. Where horizontal guilding wheels are provided, the wheelbase shall be the distance between therail contact points of two horizontal wheels.



2 - 23

The resulting loads set up in the structure shall be calculated on the basis of the retardationimparted to the appliance by the buffer in use.

However, for higher speeds (greater than 1 m/sec), the use of decelerating devices which actupon approach to the ends of the track is permitted provided the action of these devices isautomatic and they produce an effective deceleration of the appliance which always reduces thespeed to the predetermined lower value before the buffers are reached.

In this case the reduced speed obtained after slowing down is used for the value of Vt whencalculating the buffer effect 6.

In the second case where the load cannot swing the buffer effect is calculated in the samemanner but taking account of the value of the working load.

(1) It must be emphasised that a sure and effective device must be fitted. A mere end-of-travel limit switchcutting off the power supply to the motor is not sufficient reason to assume reduced speed for the buffereffect.

2.2.3.4.2. BUFFER EFFECTS ON THE SUSPENDED LOAD

Impacts due to collision between the load and fixed obstructions are taken into account only forappliances where the load is rigidly guided. In that case, the loads generated by such a collisionare to be taken into consideration.

The loads can be computed by considering that horizontal force applied at the lever of the loadwhich is capable of causing two of the crab wheels to lift.

2.2.4. LOADS DUE TO CLIMATIC EFFECTSThe loads due to climatic effects are those resulting from the action of the wind, from snow loadsand from temperature variations.

2.2.4.1 WIND ACTION

INTRODUCTIONThis clause relates to wind loads on crane structure.It gives a simplified method of calculation and assumes that the wind can blow horizontally fromany direction, that the wind blows at a constant velocity and that there is a static reaction to theloadings it applies to the crane structure.

2.2.4.1.1. WIND PRESSURE

The dynamic wind pressure is given by : q = 0.613 Vs2

Where q is the dynamic pressure N/m2., and Vs is the design wind speed in m/s.

6 Where a wind speed measuring device is to be attached to an appliance it shall normally be placed at themaximum height of the appliance. In cases where the wind speed at a different lever is more significant tothe safety of the appliance, the manufacturer shall state the height at which the device shall be placed.



2 - 24

2.2.4.1.2. DESIGN WIND CONDITIONS

Two design wind conditions are taken into account in calculating wind loads on cranes.

2.2.4.1.2.1. In-service wind

This is the maximum wind in which the crane is designed to operate. The wind loads areassumed to be applied in the least favourable direction in combination with the appropriateservice loads. In-service design wind pressures and corresponding speeds are given in tableT.2.2.4.1.2.1. They are assumed to be constant over the height of the appliance 7.

It is assumed that the operating speeds and nominal accelerations are not necessarily reachedunder extreme wind conditions.

Table T.2.2.4.1.2.1. - In-service design wind pressure

Type of applianceWind pressure

in serviceN/m2

Wind speedin service

m/sLifting appliance easily protectedagainst wind action or designedfor use exclusively in light wind.

Erection operations.125 14

All normal types of craneinstalled in the open

250 20

* Appliances which mustcontinue to work in high winds

500 28

* For example appliances of type 12a in table T.2.1.2.5.

Action of wind on the load

The action of the wind on the hook load for a crane which handles miscellaneous loads shall bedetermined from the relationship :

F = 2,5 . A . qwhere :

F is the force exerted by the wind on the hook load in N,

7 (1) Where, exceptionally, a crane is required to handle loads of large surface area, it is admissible for themanufacturer to determine a wind speed less than that specified in table T.2.2.4.1.2.1. above which suchloads shall not be handled.



2 - 25

q is the in-service wind pressure from table 2.2.4.1.2.1. in N/m2,

A is the maximum area of the solid parts of the hook load in m2 8. Where this area is notknown, a minimum value of 0.5 m2 per tonne of safe working load shall be used.

Where a crane is designed to handle loads of a specific size and shape only, the wind loadingshall be calculated for the appropriate dimensions and configurations.

2.2.4.1.2.2. Wind out of service

This is a maximum (storm) wind for which the lifting machine is designed to remain stable in outof service conditions, as indicated, by the manufacturer. The speed varies with the height of theapparatus above the surrounding ground lever, the geographical location and the degree ofexposure to the prevailing winds.

For lifting appliances used in the open air, the normal theoretical wind pressure and thecorresponding speed, for "out of service" conditions are indicated in the table T.2.2.4.1.2.2.

Table T.2.2.4.1.2.2. - Out of service wind

Height above ground lever

m

Out of service designwind pressure

N/m2

Approximate equivalentout of service design

wind speed m/s0 to 20

20 to 100More than 100

8001 1001 300

364246

When calculating wind loads for out of service conditions the wind pressure may be taken asconstant over the vertical height intervals in table T.2.2.4.1.2.2. Alternatively, the design windpressure at the top of the crane may be assumed constant over its entire height.

Where cranes are to be permanently installed or used for extended periods in areas where windconditions are exceptionally severe, the above figures may be modified by agreement betweenthe manufacturer and purchaser in the light of local meteorological data.

For certain types of appliance of which the jib can be quickly lowered, (such as a tower cranewhich can be easily lowered by a built-in mechanism) the out of service wind need not be takeninto consideration provided the machine is intended for lowering after each working day.

8 Where, execptionnally, a crane is required to handle loads of large surface area, it isadmissible for the manufacturer to détermine a wind speed less than that spécifie in tableT.2.2.4.1.2.1. above wich such loads shall not be handled.



2 - 26

2.2.4.1.3. WIND LOAD CALCULATIONS

For most complete and part structures, and individual members used in crane structures thewind load is calculated from :

F = A . q . Cf

Where :F is the wind load in N,

A is the effective frontal area of the part under consideration in m2,

q is the wind pressure corresponding to the appropriate design condition in N/m2,

Cf is the shape coefficient in the direction of the wind for the part under consideration.

The total wind load on the structure is taken as the sum of the loads on its component parts.

In determining strength and stability requirements of the appliance the total wind load shall beconsidered.

The magnitude of the wind load to be allowed for in the design of a mechanism, in determiningthe motor and brake requirements for the mechanism and to provide for the safety of theappliance in the wind, are given in the chapter dealing with the design of mechanisms.

2.2.4.1.4. SHAPE COEFFICIENTS

2.2.4.1.4.1. Individual members, frames, etc.

Shape coefficients for individual members, single lattice frames and machinery houses aregiven in table T.2.2.4.1.4.1. The values for individual members vary according to the aerodynamicslenderness and, in the case of large box sections, with the section ratio. Aerodynamicslenderness and section ratio are defined in figure 2.2.4.1.4.1.

The wind load on single lattice frames may be calculated on the basis of the coefficients for theindividual members given in the top part of table T.2.2.4.1.4.1. In this case the aerodynamicslenderness of each member shall be taken into account. Alternatively the overall coefficients forlattice frames constructed of flat sided and circular sections given in the middle part of the tablemay be used.

Where a lattice frame is made up of flat-sided and circular sections, or of circular sections inboth flow regimes (D.VS < 6 m2/s and D.VS ≥ 6 m2/s) the appropriate shape coefficients areapplied to the corresponding frontal areas.

Where gusset plates of normal size are used in welded lattice construction no allowance for theadditional area presented by the plates is necessary, provided the lengths of individualmembers are taken between the centres of node points.



2 - 27

Shape coefficients obtained from wind-tunnel or full-scale tests may also be used.

Table T.2.2.4.1.4.1. - Force coefficients

Aerodynamic Slenderness l/b or l/D (1)Type Description ≤ 5 10 20 30 40 50 > 50

Rolled sections [ ]

Rectangular hollowsections up to356 mm square

and 254 x 457 mmrectangular

1,15

1,4

1,05

1,15

1,45

1,05

1,3

1,5

1,2

1,4

1,55

1,3

1,45

1,55

1,4

1,5

1,55

1,5

1,6

1,6

1,6

Other sections 1,30 1,35 1,60 1,65 1,70 1,80 1,80Individualmembers

Circular sections where :

D.Vs < 6 m2/sD.Vs ≥ 6 m2/s

0,600,60

0,700,65

0,800,70

0,850,70

0,900,75

0,900,80

0,900,80

Rectangularhollow sectionsover 356 mmsquare and254 x 457 mmrectangular

Wind →

b/d21

0,50,25

1,551,401,00,80

1,751,551,200,90

1,951,751,300,90

2,101,851,351,0

2,201,901,401,0

Flat-sided sections 1,70Singlelatticeframes

Circular sections where :

D.Vs < 6 m2/sD.Vs ≥ 6 m2/s

1,100.80

Machineryhousesetc.

Rectangular cladstructures on groundor solid base

1,10

(1) See figure 2.2.4.1.4.1.

b

d



2 - 28

(I) Aerodynamic slenderness :( length of member ) / ( breadth of section across wind front ) = l/b * or l/D *

* In lattice construction the lengths of individual members are taken between the centres ofadjacent node points. See diagram below

(II) Solidity ratio : (area of solid parts) / (enclosed area) = A /Ae = 1

n

∑ [(li . bi)/(L . B)]

(III) Spacing ratio :(distance between facing sides) / (breadth of members across wind front ) = a/b or a/B

for "a" take the smallest possible value in the geometry of the exposed face.

(IV) Section ratio :(breadth of section across wind front) / (depth of section parallel to wind flow)= b/d

Figure 2.2.4.1.4.1. - Definitions : Aerodynamic Slenderness, Solidity Ratio,Spacing Ratio, and Section Ratio



2 - 29

2.2.4.1.4.2. Multiple frames of members : shielding factors

Where parallel frames or members are positioned so that shielding takes place, the wind loadson the windward frame or member and on the unsheltered parts of those behind it are calculatedusing the appropriate shape coefficients. The wind load on the sheltered parts is multiplied by ashielding factor η given in table T.2.2.4.1.4.2. Values of η vary with the solidity and spacing ratiosas defined in figure 2.2.4.1.4.1.

Table T.2.2.4.1.4.2. - Shielding coefficients

Spacing ratio Solidity ratio A/Ae

a/b 0,1 0,2 0,3 0,4 0,5 ≥0,60,51,02,04,05,06,0

0,750,920,951,01,01,0

0,400,750,800,880,951,0

0,320,590,630,760,881,0

0,210,430,500,660,811,0

0,150,250,330,550,751,0

0,100,100,200,450,681,0

Where a number of identical frames or members are spaced equidistantly behind each other insuch a way that each frame shields those behind it, the shielding effect is assumed to increaseup to the ninth frame and to remain constant thereafter.The wind loads are calculated as follows :

On the 1st. frame F1 = A.q.Cf in N

On the 2nd. frame F2 = η.A.q.Cf in N

On the n.th frame Fn = η (n-1).A.q.Cf

(where n is from 3 to 8) in N

On the 9th and subsequent F9 = η8.A.q.Cf in Nframes

The total wind load is thus :

Where there are up to 9 frames Ftotal = [1 + η + η2 + η3 + .... + η(n-1)].A.q.Cf

= [(1 - ηn) / (1 - η)].A.q.Cf in N

Where there are more than Ftotal = [1 + η + η2 + η3 + .... + n8 + (η - 9)8].A.q.Cf

9 frames = [(1 - η9) / (1 - η) + (n - 9) η8].A.q.Cf in N

Note - The term ηx used in the above formula is assumed to have a longer limit of 0.10. It is taken

as 0.10 whenever ηx < 0.10.



2 - 30

2.2.4.1.4.3. Lattice towers

In calculating the "face-on" wind load on square towers, in the absence of a detailed calculation,the solid area of the windward face is multiplied by the following overall force coefficient :For towers composed of flat sided sections 1,7 (1 + η)For towers composed of circular sections

where D.Vs < 6 m2/s 1,1 (1 + η)where D.Vs ≥ 6 m2/s 1,4

The value of η is taken from table 2.2.4.1.4.2. for a/b = 1 according to the solidity ratio of thewindward face.

The maximum wind load on a square tower occurs when the wind blows on to a corner. In theabsence of a detailed calculation, this load can be considered as 1.2 times that developed with"face-on" wind on one side.

2.2.4.1.4.4. Parts inclined in relation to the wind direction

Individual members. frames, etc.

Where the wind blows at an angle to the longitudinal axis of a member or to the surface of aframe, the wind load in the direction of the wind is obtained from :

F = A.q.Cf sin2 θ in N

where F, A, q and Cf are as defined in 2.2.4.1.3.and θ is the angle of the wind (θ < 90°) to the longitudinal axis or face.

Lattice trusses and towers

Where the wind blows at an angle to the longitudinal axis of a lattice truss or tower, the wind loadin the direction of the wind is obtained from :

F = A.q.Cf.K2 in Nwhere :F, A, q and Cf are as defined in 2.2.4.1.3. and K2 = θ / [50 (1,7 - Sp/S)]which cannot be less than 0,35 or greater than 1.

θ is the angle of the wind in degrees (θ < 90°) to the longitudinal axis of the truss or tower.

Sp is the area in m2 of the bracing members of the truss or tower projected on to its windwardplane.

S is the area in m2 of all (bracing and main) members of the truss or tower projected on to itswindward plane.

The value of K2 is assumed to have lower and upper limits of 0.35 and 1.0 respectively. It is takenas 0.35 whenever the calculated value < 0.35 and as 1.0 whenever the calculated value > 1.0.



2 - 31

2.2.4.2. SNOW LOAD

Snow loads shall be neglected in the design calculations for overhead travelling cranes, bridgecranes and jib cranes.

2.2.4.3. TEMPERATURE VARIATIONS

Stresses due to temperature variations shall be considered only in special cases such as whenmembers are not free to expand.

In such cases, the maximum temperature fluctuation shall be taken to be :- 20° C to + 45° C.

2.2.5 MISCELLANEOUS LOADS

2.2.5.1. LOADS CARRIED BY PLATFORMS

Access gangways, driver 's cabine and platforms shall be designed to carry the followingconcentrated loads :

3000 N for maintenance gangways and platforms where materials may be placed,

1500 N for gangways and platforms intended only for access of personnel,

300 N as the horizontal force which may be exerted on handrails and toe-guards.

These loads are not to be used in the calculations for girders.



2 - 32

2.3. CASES OF LOADING

Three different cases of loading are to be considered for the purpose of the calculations :

- the working case without wind,

- the working case with limiting working wind,

- the case of exceptional loadings.

Having determined the various loads in accordance with section 2.2, account is taken of a certainprobability of exceeding the calculated stress, which results from imperfect methods ofcalculation and unforeseen contingencies, by applying an amplifying coefficient γC, which variesaccording to the group classification of the appliance.

The values of this coefficient γC are indicated in clause 2.3.4.

2.3.1. CASE I : APPLIANCE WORKING WITHOUT WIND

The following shall be taken into consideration : the static loads due to the dead weight SG, theloads due to the working load SL multiplied by the dynamic coefficient ψ, and the two mostunfavourable horizontal effects SH among those defined in clause 2.2.3., excluding buffer forces.

All these loads must then be multiplied by the amplifying coefficient γC specified in clause 2.3.4.,viz :

γC (SG + ψ SL + SH)

In cases where travel motion takes place only for positioning the appliance and is not normallyused for moving loads the effect of this motion shall not be combined with another horizontalmotion. This is the case for example with a dockside crane which, once it has been positioned,handles a series of loads at a fixed point.

2.3.2. CASE II : APPLIANCE WORKING WITH WIND

The loads of case I are taken to which are added the effects of the limiting working wind SW

defined under 2.2.4.1.2.1. (table T.2.2.4.1.2.1.) and, where, applicable the load due totemperature variation, viz :

γC (SG + ψ SL + SH) + SW

Note - The dynamic effects of acceleration and retardation do not have the same values in case IIas in case I, for when a wind is blowing the accelerating or braking times are not the same aswhen still conditions prevail.



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2.3.3. CASE III : APPLIANCE SUBJECTED TO EXCEPTIONAL LOADINGS

Exceptional loadings occur in the following cases :

- appliance out of service with maximum wind- appliance working and subjected to a buffer effect- appliance undergoing the tests indicated in booklet 8.

The highest of the following combinations shall be considered :

a) The loads SG due to the dead weight, plus the load Sw max due to the maximum wind asmentioned under clause 2.2.4.1.2.2. (including the reactions of the anchorages)

b) the loads SG due to the dead weight and SL due to the working load plus the greatest buffereffect ST as envisaged in clause 2.2.3.4.

c) the loads SG due to the dead weight plus the highest of the two loads ψρ1 SL and ρ2 SL ; ρ1

and ρ2 being the coefficients by which the safe working load is multiplied for the dynamic

test (ρ1) and for the static test (ρ2) as in clauses 8.1.1. and 8.1.2.These three cases are expressed by the formulae :

a) SG + Sw max

b) SG + SL + ST 9

c) SG + ψρ1 SL or SG + ρ2 SL

Note 1 - It should be noted that the checks under (c) are only to be made in cases where theworking load, when assumed to act alone, produces stresses opposed in direction to thosecaused by the dead weight up to the point at which the static test load does not exceed 1,5 timesthe safe working load.

Note 2 - When using decelerating devices in advance of buffer impact under the conditionsmentioned in clause 2.2.3.4.1. ST will be taken to be the highest load resulting either from theretardation previously caused by the decelerating device or from that finally caused by the buffer.

9 Loadings resulting from the working load are taken into account but the effects of load swingresulting from the stock are neglected because this swing only loads the structure when theother effects have been practically absorbed. This comment does not apply to rigidly guide loadswhich cannot swing.



2 - 34

2.3.4. CHOOSING THE AMPLIFYING COEFFICIENT γγγγC

The value of the amplifying coefficient γc depends upon the group classification of the appliance.

Table T.2.3.4. - Values of amplifying coefficient γγγγC

Appliancegroup A1 A2 A3 A4 A5 A6 A7 A8

γc 1,00 1,02 1,05 1,08 1,11 1,14 1,17 1,20

2.4. SEISMIC EFFECTS

In general the structures of lifting appliances do not have to be checked for European seismiceffects.

However, if official regulations or particular specifications so prescribe, special rules orrecommendations can be applied in areas subject to earthquakes.

This requirement shall be advised to the supplier by the user of the installation who shall alsoprovide the corresponding seismic spectra.



2 - 35

2.5. LOADS ENTERING INTO THE DESIGN OF MECHANISMS

Mechanisms are subjected to two kinds of loading :

a) The loads, represented by the symbol SM, which are directly dependent upon the torquesexerted on the mechanisms by the motors or the brakes.

b) The loads, represented by the symbol SR, which are independent of motor or brake actionbut which are determined by the reactions which act upon the mechanical parts and whichare not balanced by a torque acting on the drive shafts 10.

2.5.1. TYPE SM LOADS

The loads of this type to be considered are :

a) SMG loads, corresponding to a vertical displacement of the centre of gravity of moving partsof the appliance other than the working load.

b) SML loads, corresponding to a vertical displacement of the working load as defined inclause 2.2. for structures.

c) SMF loads, corresponding to frictional forces which have not been allowed for in calculatingthe efficiency of the mechanism (see clause 4.2.6.1.1., booklet 4).

d) SMA loads, associated with acceleration (or braking) of the motion.

e) SMW loads, corresponding to the effect of the working wind assumed for the appliance.

2.5.2. TYPE SR LOADS

The loads of this type to be considered are :

a) SRG loads due to the weights of components which act on the part under consideration ;b) SRL loads due to the working load as defined in clause 2.2., for structures.c) SRA loads due to the accelerations or decelerations of the various motions of the

appliance or its parts, as calculated according to clause 2. 2.3.1. for structures, insofar asthe order of magnitude of these loads is not negligible compared to the SRG and SRL loads.

d) SRW loads due to the limiting working wind SW or to the maximum wind SW max (see clause2.2.4.1.), insofar as the order of magnitude of these loads is not negligible.

10 In a travel motion, for instance, the loads due to the vertical reaction on the rail wheels and thetransverse loads that stress the wheel axle but are not transmitted to the components of thedriving mechanism.



2 - 36

2.6. CASES OF LOADINGThree cases of loading are to be considered in the calculations :

Case I : Normal service without windCase II : Normal service with windCase III : Exceptional loadings.

A maximum load must be determined for each case of loading which serves as the basis for thecalculations.

Note - Clearly, case I and II are one and the same in the case of appliances which are notexposed to wind.

The various loadings being determined as indicated in paragraph 2.5., account is taken of acertain probability of exceeding the calculated stress, which results from imperfect methods ofcalculation and unforeseen contingencies, by applying an amplifying coefficient γm depending on

the group in which the mechanism is classified. The values of this coefficient γm are indicated intable T.2.6.

Table T.2.6. - Values of amplifying coefficient γγγγm

Mechanismgroup M1 M2 M3 M4 M5 M6 M7 M8

γm 1,00 1,04 1,08 1,12 1,16 1,20 1,25 1,30

2.6.1. CASE I - NORMAL SERVICE WITHOUT WIND

2.6.1.1. TYPE SM LOADS

The maximum load SM max I of the SM type (see clause 2.5.) is determined by combining the loadsSMG, SML, SMF, and SMA defined in clause 2.5.1. which can be expressed by the relation :

SM max I = ( SMG + SML + SMF + SMA ) γm

Note - It must be pointed out that it is not the combination of the maximum values of each of theterms in this relation that must be considered, but the value resulting from the most unfavourablecombination that could actually occur in practice.

2.6.1.2. TYPE SR LOADS

The maximum load SR max I of the SR type (see clause 2.5.) is determined by combining the loadsSRG, SRL, SRA, defined in clause 2.5.2. which can be expressed by the relation :

SR max I = ( SRG + SRL + SRA ) γm

The note in clause 2.6.1.1. above applies here also.



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2.6.2. CASE II - NORMAL SERVICE WITH WIND


The maximum load SM max II of the SM type (see clause 2.5.) is determined by combining the loadsSMG, SML and SMF defined in clause 2.5.1. with one of the following two combinations :

a) the load SMA and the load SMW 8 corresponding to a 80 N/m2 wind.

b) the load SMW 25 corresponding to a 250 N/m2 wind.

The higher of the two values expressed by the relations set out below is taken :

SM max II = ( SMG + SML + SMF + SMA + SMW 8 ) γm

or

SM max II = ( SMG + SML + SMF + SMW 25 ) γm

The note in clause 2.6.1.1. applies here also.


The maximum load SR max II of the SR type (see clause 2.5.) is determined by combining the loadsSRG, SRL and SRA defined in clause 2.5.2. with SRW 25 which corresponds to a 250 N/m2 wind, asexpressed by the relation :

SR max II = ( SRG + SRL + SRA + SRW 25 ) γm

The note in clause 2.6.1.1. applies here also.



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2.6.3. CASE III - EXCEPTIONAL LOADS


The maximum load SM max III of the SM type defined under clause 2.5. is determined byconsidering the maximum load that the motor can actually transmit to the mechanism, allowingfor limitations due to practical operating conditions.

The values of SM max III are specified in clause 2.6.4.


Since the consequences of an overload due to collision with a buffer or fouling are far lessserious for a mechanism than for the structure, the exceptional loading to be taken is that givenunder paragraph a) of clause 2.3.3. in the structures chapter.

This gives : SR max III = ( SRG + SRW max )

In cases where additional mooring or guying means are used to ensure immobility or stabilityunder maximum wind, the effect of these devices on the mechanism must be taken into accountwhere applicable.

2.6.4. APPLICATION OF THE ABOVE CONSIDERATIONS FOR CALCULATINGSM

The mechanisms of hoisting appliances perform one of the following functions :

- Purely vertical displacements of the centre of gravity of moving masses (e.g. hoistingmotions).

- Purely horizontal displacements in which the centre of gravity of the moving masses as awhole shifts horizontally (e.g. traverse, travel, slewing or counterbalanced luffing motions).

- Movements combining an elevation of the centre of gravity of the moving masses with ahorizontal displacement (e.g. non-counterbalanced luffing).



2 - 39

2.6.4.1. HOISTING MOTIONS

For type SM loads, the formula reduces to the following :

Case I and II : SM max I = ( SML + SMF ) γm

In this case the load due to the hoisting acceleration is neglected because it is small comparedto SML.

Case III : SM max III = 1,6 ( SML + SMF )

Bearing in mind the general rules of clause 2.6.3.1., it is assumed that the maximum loads thatcan be transmitted to hoisting mechanisms are limited in practice to 1,6 times the SM max I load 11.

2.6.4.2. HORIZONTAL MOTIONS

Case I - The formula reduces to :

SM max I = ( SMF + SMA ) γm

Case II - The higher of the following two values is taken :

SM max II = ( SMF + SMA + SMW 8 ) γm

or

SM max II = ( SMF + SMW 25 ) γm

Case III - For SM max III the load corresponding to the maximum torque of the motor (or the brake)is taken unless operating conditions limit the torque actually transmitted, through wheel slip onthe rails, or through the use of suitable limiting means (e.g. hydraulic coupling, torque limiter,etc.). In this case the value actually transmitted must be taken 12.

11 In a hoisting motion it is impossible under normal working conditions to transmit to the mechanism loadsgreater than those due to the hoisting of the working load, as the effects of acceleration are negligible.A greater load could result only from mishandling (poor judgement of the load, etc.).On the basis of experience gained over many years of practice with widely differing hoistingappliances it is now accepted that a coefficient of 1,6 gives adequate safety. It must be stressedthat the use of excessively powerful motors should be avoided.12 Whereas in the case of hoisting motions the loads normally transmitted to the mechanism are limited by theload lifted, in horizontal motions the maximum torque of the motor can always be transmitted to themechanism if no mechanical limitation exists. This is why a different way of evaluating SM max III has beenspecified according to whether a hoist motion or other motion is being considered.



2 - 40

2.6.4.3. COMBINED MOTIONS

Case I and II :For cases I and II, the load SM max II

13 is determined by applying the general formula defined inclauses 2.6.1.1. and 2.6.2.1.

Case III :The load caused by applying the maximum motor torque SMC max III can be taken for the maximumvalue SM max III This often unduly high value is always acceptable since it enhances safety.

It must be used when the power involved for raising the centres of gravity of the moving massesis negligible compared to the power needed to overcome accelerations or wind effects.

Conversely, when the effect of the accelerations or the wind is negligible in comparison with theeffect of displacing the centres of gravity of the moving masses vertically, this value is too highand SM max III can be calculated from the formula :

SM max III = 1,6 SM max II

Between these two limiting values, each individual case should be examined according to themotor chosen, the method of starting and the relative magnitudes of the loads due to inertia andwind effects on the one hand and those due to raising of the centres of gravity on the other.

Without exception, when operating conditions limit the torque actually transmitted to themechanism (see clause 2.6.4.2.), this limiting torque will be taken as the value of SMC max if it isless than the values defined above.

.

13 or SM max I in the case of appliances not subjected to wind.



2 - 41

APPENDIX

A.2.1.1. - HARMONISATION OF THE CLASSES OF UTILIZATION OFAPPLIANCES AND MECHANISMS

The present appendix sets out to demonstrate a method by which it is possible in many cases toderive the class of utilization of mechanisms from that of appliances as a whole and from certainparameters characterising the duty to be performed.

The starting point is the average duration tmc (in seconds) of a hoisting cycle as defined in clause2.1.2.2. This is therefore the time necessary to perform all the operations in such a cycle.

The total duration of use T of the appliance, expressed in hours, is then given by the relation :

T = N.tmc / 3600

Where N represents the number of hoisting cycles determining the class of utilization of theappliance.

Table T.A.2.1.1.1. gives the values of T for cycle durations of 30 - 480 s in accordance with theclass of utilization of the appliance. The number of hoisting cycles is the maximum number forthis class of utilization ; these values are, however, adjusted to 15 625, 31 250 and 62 500respectively for class U0, U1 and U2, in order to reduce the number of different values for T.

The next step is to determine for each mechanism the ratio αi between the duration of use of themechanism during a hoisting cycle and the average duration tmc of the cycle.

Table T.A.2.1.1.2. gives the total durations of use Ti of the mechanism depending on the totalduration of use of the appliance, and for various conventional values of the ratio αi . This tablealso shows the class of utilization of the mechanism. The various classes are represented bythe stepped areas.

It is thus sufficient to determine the class of utilization of the appliance by reference to tableT.2.1.2.2., the average duration of the hoisting cycle and the values of αi in order to obtain theclasses of utilization of the mechanisms.

From the curves of the nomogram T.A.2.1.1.3. the classes of utilization for the mechanisms interms of these three parameters can be found directly.



2 - 42

Table T.A.2.1.1.1. - Total duration of use (T) of lifting appliances in hours

Averagedurationof a

Class of utilization of appliances

hoisting cycletmc (s)

U0 U1 U2 U3 U4 U5 U6 U7 U8 U9

30

45

60

75

90

120

150

180

240

300

360

420

480

130

195

260

325

390

520

650

780

1 040

1 300

1 565

1 825

2 085

260

390

520

650

780

1 040

1 300

1 565

2 085

2 605

3 125

3 645

4 165

520

780

1 040

1 300

1 565

2 085

2 605

3 125

4 165

5 210

6 250

7 290

8 335

1 040

1 565

2 085

2 605

3 125

4 165

5 210

6 250

8 335

10 415

12 500

14 585

16 665

2 085

3 125

4 165

5 210

6 250

8 335

10 415

12 500

16 665

20 835

25 000

29 165

33 335

4 165

6 250

8 335

10 415

12 500

16 665

20 835

25 000

33 335

41 665

50 000

58 335

66 665

8 335

12 500

16 665

20 835

25 000

33 335

41 665

50 000

66 665

83 335

100 000

116 665

133 335

16 665

25 000

33 335

41 665

50 000

66 665

83 335

100 000

133 335

166 665

200 000________> 200 000

> 200 000

33 335

50 000

66 665

83 335

100 000

133 335

166 665

200 000________> 200 000

> 200 000

> 200 000

> 33 335

> 50 000

> 66 665

> 83 335

> 100 000

> 133 335

> 166 665________> 200 000



2 - 43

Table T.A.2.1.1.2. - Total duration of use Ti (in hours) of mechanisms in terms of T and ααααi

T Values of αi Class ofutilization for

(h) 1,00 0,63 0,40 0,25 0,16 0,10 mechanism130 130 82 52 33 21 13195 195 123 78 49 31 20260 260 164 104 65 42 26325 325 205 130 81 52 33390 390 246 156 98 62 39520 520 328 208 130 83 52 T0650 650 410 260 163 104 65780 780 491 312 195 125 78

1 040 1 040 655 416 260 166 1041 300 1 300 819 520 325 208 1301 565 1 565 986 626 391 250 1571 825 1 825 1 150 730 456 292 1832 085 2 085 1 314 834 521 334 2092 605 2 605 1 641 1 042 651 417 261 T13 125 3 125 1 969 1 250 781 500 3133 645 3 645 2 296 1 458 911 583 3654 165 4 165 2 624 1 666 1 041 666 4175 210 5 210 3 282 2 084 1 303 834 521 T26 250 6 250 3 938 2 500 1 563 1 000 6257 290 7 290 4 593 2 916 1 823 1 166 7298 335 8 335 5 251 3 334 2 084 1 334 834

10 415 10 415 6 561 4 166 2 604 1 666 1 042 T312 500 12 500 7 875 5 000 3 125 2 000 1 25014 585 14 585 9 189 5 834 3 646 2 334 1 45916 665 16 665 10 499 6 666 4 166 2 666 1 66720 835 20 835 13 126 8 334 5 209 3 334 2 084 T425 000 25 000 15 750 10 000 6 250 4 000 2 50029 165 29 165 18 374 11 666 7 291 4 666 2 91733 335 33 335 21 001 13 334 8 334 5 334 3 33441 665 41 665 26 249 16 666 10 416 6 666 4 167 T550 000 50 000 31 500 20 000 12 500 8 000 5 00058 335 58 335 36 751 23 334 14 584 9 334 5 83466 665 66 665 41 999 26 666 16 666 10 666 6 66783 335 83 335 52 501 33 334 20 834 13 334 8 334 T6

100 000 100 000 63 000 40 000 25 000 16 000 10 000116 665 116 665 73 499 46 666 29 166 18 666 11 667133 335 133 335 84 001 53 334 33 334 21 334 13 334166 665 166 665 104 999 66 666 41 666 26 666 16 667 T7200 000 200 000 126 000 80 000 50 000 32 000 20 000

> 200 000 > 200 000 > 126 000 > 80 000 > 50 000 > 32 000 > 20 000T8

T9



2 - 44

Table T.A.2.1.1.3. - Classes of utilization for appliances and mechanisms

U - Class of utilization for appliances T - Class of utilization for mechanisms



2 - 45

EXAMPLE OF APPLICATION

Dockside cargo crane.

The class of utilization for the appliance will be U5.

A hoisting cycle comprises the following operations :

- hoisting of load ;- travelling ;- slewing ;- lowering ;- unhooking of load ;- hoisting empty ;- slewing ;- travelling ;- lowering empty ;- hooking on of new load.

The average time for completion of the cycle will be estimated at 150 s.

The ratios αi will be estimated as follows :

- hoisting (hoisting and lowering) : αi = 0.63

- slewing (2 directions) : αi = 0.25

- travelling (do.) : αi = 0.10

Table T.A.2.1.1.1. gives us for class U5 and tmc = 150 s :

T = 20 835 h

For the various mechanisms, table T.A.2.1.1.2. gives us, for T = 20 835 h, the following totaldurations Ti and classes of utilization :

- hoisting (αi = 0.63) : Ti = 13 126 h T7

- slewing (αi = 0.25) : Ti = 5 209 h T5

- travelling (αi = 0.10) : Ti = 2 084 h T4

From the curves in table T.A.2.1.1.3. the same conclusions are drawn on the basis of theordinate tmc = 150 s (broken line).



2 - 46

A.2.2.3. - CALCULATION OF LOADS DUE TO ACCELERATIONS OFHORIZONTAL MOTIONS

PART 1 - METHOD

1. - BASIC DATA

Let

v be the steady horizontal velocity of the point of suspension of the load, either at the end ofthe acceleration period, or at the beginning of the braking period, according to whether anacceleration or a braking process is being considered, and

F an imaginary horizontal force in the same direction as v, applied at the point of suspensionof the load and producing the same effect on the motion under consideration as theaccelerating or decelerating torque applied by the motor or the brake.

2. - PROCEDURE

The different quantities set out below must be calculated in succession.

Equivalent mass (m)

The inertia of all moving parts other than the load, in the motion under consideration, is replacedby a single equivalent mass m assumed to be concentrated at the point of suspension of theload and given by the relation :

m = m0 + i∑ [ ( Ii . wi

2) / v2 ]

Where :

m0 is the total mass of all elements, other than the load, undergoing the same pure linearmotion as the point of suspension of the load ;

Ii the moment of inertia of a part undergoing a rotation during the motion under consideration,this moment of inertia being considered about the axis of rotation, and

wi the angular velocity of the part referred to, about its axis of rotation, corresponding to thelinear velocity v of the point of suspension of the load.

The sum Σ covers all parts in rotation (structure, mechanisms, motor) during the motionconsidered. However, in the case of mechanisms, the inertia of components other than thosedirectly coupled to the motor shaft can be ignored.

Mean acceleration or deceleration ( Jm ) :Jm = F / (m + m1 )

where m1 is the mass of the load.



2 - 47

Mean duration of acceleration or deceleration ( Tm ) :

Tm = v / Jm

Mean inertia forces :

The acceleration corresponding to the acceleration Jm at the point of suspension of the load iscalculated for each component part in motion. Multiplying this acceleration by the mass of thecomponent considered gives the mean inertia force it sustains.

In the particular case of the load itself, this force of inertia Fcm will be given by :

Fcm = m1 . Jm

Period of oscillation : Tl T1 = 2 . π . ( l / g )0,5

l = the length of suspension of the load when it is in its uppermost position (values of l below2,00 m need not be taken into consideration) and,

g = the acceleration due to gravity.

Value of µ : µ = m1 / m

When the system driving the motion controls the acceleration and the deceleration andmaintains it at a constant value, µ is taken equal to 0 irrespective of the masses m and m1.

Value of β : β = Tm / T1

Value of ψh :

With the values obtained for µ and β, the graph in figure A.2.2.1. is used to find the corresponding

value ψh.

Inertia forces to be considered in the design of the structure :

The forces of inertia which take account of dynamic effects and which must therefore beconsidered in the structural calculations are obtained as follows :

- Inertia force due to the load : ψh . Fcm

- Inertia force on moving parts other than the load : twice the mean inertia forces.

3. - JUSTIFICATION

A justification of the method given above follows in part 2 of this appendix.



2 - 48

PART 2 - EXPLANATION OF THE METHOD

1. - STATEMENT OF THE PROBLEM

A hoisting appliance is a physical system consisting essentially of :

- concentrated masses (hook load, counterweights, ...) and distributed masses (girders,ropes, ...),

- elastic connections between these masses (girders, ropes, ...).

If such a system, originally in a state of equilibrium, is subjected to a varying load, it does nottend progressively towards a new state of equilibrium even if the new load applied is itselfconstant. On the contrary, it is set in a more or less complex oscillating motion about this newstate of equilibrium. During this motion, the various internal loads and stresses of the systemcan exceed sometimes to a marked extent - the values they would have assumed had thesystem been in static equilibrium under the influence of the new load.

Such a situation arises during acceleration or deceleration (braking) of a horizontal motion of ahoisting appliance. Thus if, starting from a position of rest, an appliance or part of an appliancebegins a motion of translation or rotation, the component parts of the system undergoaccelerations and are therefore subjected to inertia forces. Once a steady speed is attained, theacceleration ceases, the inertia forces disappear and the external load undergoes a newvariation.

The angle through which a rotating system turns (e.g. the rotating part of a crane) during the timefor which inertia forces are applied is generally relatively small. This being so, no appreciableerror will be involved if one assumes that each point in the system follows a straight path duringthis time. Since, moreover, there is no difference of principle between the treatment used forlinear motions and motions of rotation, in what follows the linear motion will be considered ingreater detail (chapter 2), whereas only a short note (chapter 3) will cover rotation.



2 - 49

2. - CALCULATING THE LOADS IN THE CASE OF A LINEAR MOTION

2.1. - GENERAL DATA

It is now proposed to examine the particular case of braking of the travel motion of a completeoverhead travelling crane when it is carrying a load suspended from its hoisting rope. Othercases encountered in practice can be dealt with in similar fashion.

Considering figure A.2.1. let :m1 be the mass of the suspended load,m the total mass of the overhead travelling crane including the crab (see note below

concerning the inertia of the motor and of the machinery driving the motion),x a coordinate defining the position of the crane along its track (more precisely, x represents

the coordinate of the point of suspension of the hoisting rope along an axis parallel to thedirection of travel),

x1 a coordinate defining the position of the centre of gravity of the suspended load along anaxis of the same direction, sense and origin as the axis of x ,

z = x1 - x a coordinate expressing the horizontal displacement of the load relative to the crane.

Let us assume that at the instant t = 0 the overhead travelling crane is moving in the positivesense of the x axis at a velocity v, and that the load is at rest relative to the crane.

( z = z' = 0, with : z' = dz / dt )

If the brake is applied to the travel mechanism at the instant t = 0, it will give rise from that instantto a horizontal braking force parallel to, but of opposite sense to, the x axis at each point where adriving wheel is in contact with its rail. To simplify masters, let us assume that the crab is locatedat mid-span of the main girders of the overhead travelling crane. It follows by symmetry that thetotal force at each rail is the same. Let us designate its projection on the x axis by F/2 (with F > 0),so that the total braking force acting on the system in motion 2 (crane plus load) is equal to F inabsolute value.

If the system were composed of rigidly interconnected masses, this would result in adeceleration of absolute value Jm given by the relation : Jm = F / ( m +m1 ) (2.1.1)



2 - 50

Figure A.2.1.

It must not be forgotten however that F originates in the braking torque applied to the travelmechanism which must not only brake the travel inertia of the crane and the load but also therotational inertia of the driving motor and the intervening machinery. Generally speaking, one canneglect the rotating inertia of all components other than those integral with the motor shaft. Inmany cases, however, the inertia of the latter must be taken into account and the relation (2.1.1.)holds good only provided that m incorporates an equivalent mass me given by the relation :

me . v2 = Im . ωm

2 (2.1.2.)where :

Im is the moment of inertia of all the components integral with the motor shaft (including themotor itself, of course) and

ωm the angular velocity of the motor corresponding to the travelling speed v of the crane.

Under the effect of the deceleration Jm, the suspension rope cannot retain its vertical position. Itsnew position of equilibrium is inclined to the vertical at an angle αm given by the relation :

αm = arctg( Jm / g ) (2.1.3.)

where g is the acceleration due to gravity. In this case the rope exerts a horizontal force on thecrane whose projection Fcm on the x axis is given by :

Fcm = m1 . Jm (2.1.4.)



2 - 51

In point of fact, the system is not rigid, the deceleration is not constant and is not therefore givenby (2.1.1.), the load and its suspension rope adopt an oscillating motion, and the horizontal forcedeveloped by the rope on the crane can assume values differing greatly from (2.1.4.).

By a similar reasoning, one may conclude that the deceleration of the system gives rise to inertiaforces which act on each component part of the crane and the crab, but that because of theelasticity of the girders the system will undergo an oscillating motion in the course of which thestresses will be subject to fluctuations which must be estimated.

The next two paragraphs deal in succession with the effect of the inertia forces on the load andon the girders.



2 - 52

2.2. - EFFECT OF INERTIA FORCES ON THE LOAD

In determining the motion which the load executes after the brake is applied, one can neglect themovement of the point of suspension due to girder flexibility in a horizontal plane. The amplitudeof this movement is, in fact, very small compared with the amplitude of swinging of the load.Calculations can therefore be carried out with the crane considered as a system which is notsubject to deformation.

The projection FC on the x axis of the force exerted by the rope on the crane is given by therelation :

FC= m1 . g [( x1 - x ) / l] = m1 . g . z / l (2.2.1)where l is the suspension length of the load. It will be noted that FC is proportional to thedisplacement z of the load with respect to its position of initial equilibrium, just as if it were anelastic restoring force.

The equations of motion can be written :

ml . x’’1 = m1 . g [( x1 - x ) / l] (2.2.2.)

m . x’’ = m1 . g [( x1 - x ) / l] - F (2.2.3.)

while, assuming x = 0, for t = 0, the initial conditions are as follows :

for t = 0, x1 = x = 0 (2.2.4.)

x'1 = x' = v (2.2.5.)

z = x1 - x = 0 (2.2.6.)

z’ = x’1 - x’ = 0 (2.2.7.)

Let :g / l = ω1

2 (2.2.8.)

(m1 / m) . (g / l) = ω22 (2.2.9.)

ω12 + ω2

2 = ωr2 (2.2.10.)

F / m = J0 (2.2.11.)

Equations (2.2.2.) and (2.2.3.) then become :

x" + z" + ω12 . z = 0 (2.2.12.)

x" - ω22 . z = - J0 (2.2.13.)

whence



2 - 53

z’’ + ωr2 . z = J0 (2.2.14.)

With the initial conditions of (2.2.4.) to (2.2.7.), the solution to these equations is given by :

z = ( J0 / ωr2 ) . [1 - cos( ωr . t)] (2.2.15.)

x' = v -[ ( ω12./ ωr

2 ) . J0 . t ] - [ ( ω22./ ωr

2 ) . ( J0 / ωr ) ] . sin(ωr . t) (2.2.16.)The complete expression for x is of no direct interest to us.

Let : J0 / ωr2 = zm (2.2.17.)

it can then be seen without difficulty that zm is the position of equilibrium that can be assumed bythe load during a constant deceleration of the crane equal to the value Jm defined by (2.1.1.), i.e.during the deceleration that would be obtained by applying the braking force F to the total mass(crane plus load) in motion, this mass being assumed to constitute a rigid system. The value z =zm defining the load displacement corresponds to the horizontal force Fcm, defined by (2.1.4.)exerted by the rope on the crane. Comparison between (2.2.1.), (2.2.15.) and (2.2.17.) thenshows that :

Fc = Fcm . [ 1 - cos(ωr . t) ] (2.2.18.)

If the deceleration period of the crane lasts for a time td such that :

ωr . td ≥ π (2.2.19.)

it will be seen that Fc momentarily becomes twice Fcm, or in other words, that its maximum valueFc max is given by the relation :

Fc max = 2 . Fcm (2.2.20.)

If the condition (2.2.19.) is not satisfied, this means that the crane has stopped before the loadhas reached its maximum displacement z = 2 zm. However, after the crane stops, the load willusually continue to oscillate, so the rope will continue to exert a varying horizontal force on thecrane, and the maximum value which this can attain must be sought.

It is easy to verify that after the crane has stopped, the motion of the load is defined by theexpression :

z = zd . cos[ ω1 . (t - td) ] + (z’d / ω1) . sin[ ω1 . (t - td) ] (2.2.21.)

withzd = zm . [ 1 - cos(ωr . td) ] (2.2.22.)

z'd = ωr . zm . sin(ωr . td) (2.2.23.)

where td is the smallest positive value of t that makes the expression (2.2.16.) for x' equal to zero.

The maximum value Fc max assumed by Fc is then given by the relation :



2 - 54

Fc max = Fcm . [ 1 - cos( ωr . td ) ]2 + ( ωr

2 / ω12 ) . sin2( ωr . td )

0,5 (2.2.24.)



2 - 55

Generally speaking, we may take :

Fc max / Fcm = ψh (2.2.25.)

The determination of ψh is simplified by introducing the following quantifies :

Tm = v / Jm the time for which the slowing-down phase of the crane would last if thedeceleration were constant and the system in motion not subject to deformation.

T1 = 2 π / ω1 the period of oscillation of the pendulum system formed by the suspended load(crane stopped).

T1 = 2 π . ( l / g )0,5

It can be verified without difficulty that ψh depends only on two non-dimensional parameters µ

and β defined by the ratios :

µ = m1 / m (2.2.26.)

β = Tm / T1 (2.2.27.)

which can be obtained very easily. It will be noted that (2.2.16.) can be written :

x’ = v . 1 - [ ωr . t + µ . sin( ωr . t ) ] / [ 2 π . β ( 1 + µ )0,5 ] (2.2.28.)

and therefore :[ ωr . td + µ . sin( ωr . td ) ] / [ 2 π . β ( 1 + µ )0,5 ] = 1 (2.2.29.)

this equation makes it possible to determine the value of ωr . td to be introduced into (2.2.24.).

The graph in figure (2.2.1.) plots the values of ψh against β for various values of µ. (The curve

µ = 0 will be explained later in Chapter 5).

If µ < 1 (which is generally the case with overhead travelling crane travel motions, such as that in

the example dealt with), an analysis of the problem shows that ψh can in no case exceed 2. Thisvalue is reached during the crane deceleration phase if the condition (2.2.19.) is satisfied or,which is the same thing, if β reaches or exceeds a certain critical value, βcrit dependent upon µ.

Above this critical value, ψh therefore remains constant and equal to 2, whatever the value of β.

If µ > 1 (which could be the case with traverse motions, in which m essentially represents only

the mass of the crab, or with slewing motions), the same analysis shows that, again provided β

reaches or exceeds a certain critical value βcrit dependent upon µ, ψh can exceed 2 and reach amaximum given by :

ψh = [ 2 + µ + ( 1 / µ ) ]0,5 (2.2.30.)



2 - 56



2 - 57

This maximum can actually be reached only during the swinging motion of the load subsequentto the bringing to rest of its point of suspension. The critical value βcrit is such that the crane ishalted before the condition (2.2.19.) is satisfied, or before Fc reaches 2 Fcm. However, any valueof β greater than βcrit leads to the condition (2.2.19.) being satisfied and Fc necessarily passes

the value 2 Fcm , whence ψh > 2. It will also be noted that if β > βcrit has been calculated taking vequal to the maximum steady speed of the motion, braking applied starting from the initial speed

v . βcrit / β

will necessarily lead to the maximum value of ψh given by (2.2.30.). This is the reason why, in the

graph of figure A.2.2.1., the values of ψh have been maintained for all values of β greater than βcrit.

Figure A.2.2.1.

As regards the choice of T1, it should be noted that the danger of reaching high values of ψh is all

the greater as the suspension length l of the load becomes shorter, because β then attains itscritical value more rapidly. The calculations must therefore be made assuming that the load isnear its uppermost position. In practice l will generally lie between 2 and 8 m. The table belowgives the values of T1 for a few values of l.

l (m) T1 (s)2345678

2,843.474.014.494.915.315.67



2 - 58

It remains for us to examine the effect of the horizontal force Fc max on the loading conditionssustained by the structure.

This force actually exist, so that any components such as the crab which transmit it directly mustbe designed to withstand it. The configuration of the load acting on the girder as a wholetherefore deserves some attention.

Let us first consider the case where Fc max occurs before the crane has come to halt. It would beincorrect to consider the latter as a beam supported at both ends and subjected at its centre tothe force Fc max. One must not lose sight of the fact that each of the two supporting points cantransmit only a reaction F/2. The successive diagrams in figure A.2.2.2. illustrate how theproblem must be considered. Diagram "a" represents the ideal state of equilibrium, in which thesystem as a whole is subjected to a deceleration Jm (or an accelerationx" = - Jm) and in which the rope develops a force Fcm. Each material element dm of the systemtherefore sustains an inertia force Jm dm. Diagram "a" is a superimposition of diagram "b" anddiagram "c". Diagram "b" relates to the load due to the inertia forces on the crane proper (this isdealt with in paragraph 2.3.), while diagram "c" shows the effect of the load due to the rope. Inpoint of fact, the actual force developed by the rope is not the force Fcm represented in diagram "c"but the force :

Fc max = ψh . Fcm (2.2.31.)

Since the supporting points (braked wheels) are not capable of increasing theirreaction, the excess force (ψh - 1)Fcm can only result in a supplementary acceleration x"expressed by :

x" = ( ψh - 1) . Fcm / m (2.2.32.)

which is translated into a distributed load - x" dm on all material elements of the crane. Diagram"d" consequently represents the loading configuration to be taken into account when designingthe girders.

Let us consider the case in which Fc max arises after the crane has halted. This time, the brakedwheels no longer have to devote part of the reaction of which they are capable to taking up theinertia forces on the crane, and in general, must be regarded as being fixed. This being so, thegirder must be designed as if it were supported at each end and subjected to the force Fc max atits centre. This latter case is in point of fact the only one which needs to be considered, becausewhen Fc reaches its maximum value 2 Fcm before the crane comes to a standstill this force canstill arise in the course of the pendulum motion which follows after it has stopped.

All the preceding considerations still hold good if, instead of considering a braking phase, one isdealing with an acceleration phase of the crane, in the course of which it is speeded up, by aconstant driving torque, from rest to a given steady speed.



2 - 59

2.3. - EFFECT OF INERTIA FORCES ON THE STRUCTURAL STEELWORK

In the previous chapter, the structure was assumed to be perfectly rigid. In fact, however, itpossesses a degree of elasticity and consequently also assumes an oscillating motion duringthe braking period and after coming to rest. Because the structure is composed essentially ofdistributed rather than simple concentrated masses, it is usually very difficult to determine themotion theoretically, and such calculations would be justified only in the case of very largeappliances in which the inertia forces play an appreciable part.

LOADING ACCELERATION

Figure A.2.2.2.



2 - 60

In almost all cases, it will suffice to represent a structure as being a simple oscillating systemhaving restoring forces proportional to the extension and subjected to the overall acceleration ofthe reference system to which it is referred. In view of the note following expression (2.2.1.) theconsiderations developed in paragraph 2.2. can be applied here also. However, the naturalperiod of the oscillations (comparable to the period T1 of paragraph 2.2.) is always appreciablyshorter than that of a suspended load, not exceeding a few tenths of a second in most cases.The result of this is that the parameter corresponding to β always exceeds the critical value βcrit,

so that ψh must always be taken equal to 2, this being the coefficient applicable to inertia loadscalculated with the mean deceleration Jm. The only exception that could be made to this rulewould be for extremely brief retardation phases, such as those resulting from braking a low-speed travel motion, with the wheels slipping on the rails.

Because the oscillating motions of the structure have a high frequency, the maximum resultingloadings are superimposed momentarily upon those due to the load.



2 - 61

3. - CALCULATING THE LOADS IN THE CASE OF A SLEWING MOTION

In the case of a slewing motion, considerations similar to those of chapter 2 can be developed.To calculate the effects of the inertia forces on the load, it is only necessary to determine m fromthe relation :

m v2 = I ω2 (3.1.)

where

v is the horizontal linear velocity of the suspension point of the load ;

I is the moment of inertia of all parts in motion (structure, machinery, motor) referred to aparticular shaft,

ω is the angular velocity of that shaft corresponding to the velocity v above.

4. - CALCULATING THE LOADS IN THE CASE OF A LUFFING MOTION

In the case of a luffing motion, considerations similar to those of chapter 2 can be developed. Itwill suffice to determine m from the relation :

m v2 = 2 T (4.1.)

wherev is the horizontal linear velocity of the suspension point of the load.

T is the total kinetic energy of the masses in motion when the horizontal linear velocity of thesuspension point of the load is equal to v.

5. - SYSTEMS WITH REGULATED ACCELERATIONIn some control systems, such as certain Ward-Leonard or hydraulically actuated systems, themagnitudes of the accelerations and decelerations are dictated by the characteristics of thesystem and are maintained constant regardless of external conditions. For this reason, loadswing does not disturb the acceleration or deceleration conditions of the appliance or part of theappliance in motion.

In the exempla dealt with in paragraph 2.2., this would be tantamount to assuming that x" is agiven constant. Using equation (2.2.12.) and its derivations, it is easy to show that in this case

ψh = 2 sinβ π for β ≤ 0,5 (5.1.)

ψh = 2 for β > 0,5 (5.1.)

Such a situation would also obtain if one assumed the mass m1 to be infinitely small comparedwith m and therefore unable to disturb its motion. This being so, (5.1.) is the limiting curveobtained by making µ tend to zero, and is represented on diagram 2.2.1. by the curve µ = 0.

The considerations in paragraph 2.3. are in no way modified.



2 - 62

6. - GENERAL CONCLUSIONSKnowing the torque or the braking or accelerating force, the first step is to calculate the meandeceleration or acceleration Jm, obtained on the assumption that the various parts of thestructure are perfectly rigid and the load is concentrated at its point of suspension. Using thisacceleration, one calculates the inertia forces acting on both the load and the various elementsof the structure. These forces are then-multiplied by a certain coefficient ψh in order to takeaccount of the elasticity of the various connections.

For the inertia forces acting on the structure ψh is always taken equal to 2, except possibly in thespecial case mentioned in the penultimate paragraph of 2.3., provided justification can beprovided for the reduction.

In the case of the inertia forces acting on the load, the mass m is calculated (incorporating,where necessary, the mass equivalent to the inertia of the motor and the mechanism) and themean deceleration or acceleration time Tm is then determined on the basis of the maximumsteady speed of the motion. The value of T1 depends on the suspension length of the load in itsuppermost position, and is therefore known. Hence one can determine the parameters µ and β

(µ = 0 in the case of a regulated-acceleration system), and figure A.2.2.1. furnishes the

corresponding value ψh. In almost all cases, the maximum force appears or can appear aftercompletion of the braking or starting phase under consideration. Its effects on the structure canbe ascertained by applying the ordinary laws of statics.

It will be noted that the calculations developed in Chapter 2 assume the load to be relatively atrest (z = z' = 0) at the initial time t = 0. If this is not so, the motion of the system is affected and ψh

can reach values considerably higher than those we have fixed. Such a situation could arise forinstance when a motion is braked by repeated intermittent applications of the brake, or whensuccessive motions take place at fairly short intervals. The method of calculation indicated aboveis therefore not excessive in any way, and special cases exist in which it would be well toexercise some caution in applying it.




SECTION I


F.E.M.

1.001 3rd EDITION

REVISED

1998.10.01


HOISTING APPLIANCES

B O O K L E T 3

CALCULATING THE STRESSES IN STRUCTURES





Booklet 3

CALCULATING THE STRESSES IN STRUCTURES

INTRODUCTION ......................................................................................................................... 3

3.1. THE CHOICE OF STEEL QUALITIES................................................................................. 4

3.1.1. ASSESSMENT OF THE FACTORS WHICH INFLUENCE BRITTLE FRACTURE........ 43.1.1.1. INFLUENCE A : COMBINED EFFECT OF LONGITUDINAL RESIDUAL TENSILESTRESSES WITH STRESSES FROM DEAD WEIGHT .....................................................................43.1.1.2. INFLUENCE B : THICKNESS OF MEMBER t........................................................................63.1.1.3. INFLUENCE C : INFLUENCE OF COLD ...............................................................................7

3.1.2. DETERMINATION OF THE REQUIRED STEEL QUALITY GROUP............................. 7

3.1.3. QUALITY OF STEELS ................................................................................................... 8

3.1.4. SPECIAL RULES......................................................................................................... 10

3.2. CHECKING WITH RESPECT TO THE ELASTIC LIMIT.................................................... 11

3.2.1. STRUCTURAL MEMBERS OTHER THAN JOINTS.................................................... 113.2.1.1. MEMBERS SUBJECTED TO SIMPLE TENSION OR COMPRESSION ...............................113.2.1.2. MEMBERS SUBJECTED TO SHEAR .................................................................................123.2.1.3. MEMBERS SUBJECTED TO COMBINED LOADS - EQUIVALENT STRESS ......................12

3.2.2. CASE OF JOINTS........................................................................................................ 133.2.2.1 RIVETED JOINTS................................................................................................................13

1 - Rivets in shear.................................................................................................................................................132 - Rivets in tension ..............................................................................................................................................133 - Rivets loaded in tension and shear ................................................................................................................144 - Limit of bearing pressure ................................................................................................................................145 - Notes concerning riveted joints ......................................................................................................................14

3.2.2.2. BOLTED JOINTS................................................................................................................143.2.2.2.0. GENERAL ............................................................................................................................................143.2.2.2.1. JOINTS MADE WITH TENSION BOLTS WITH CONTROLLED TIGHTENING...............................143.2.2.2.2. BOLTED JOINTS SUBJECTED TO FORCES ACTING PARALLEL TO THE JOINT PLANE ........18

3.2.2.3. WELDED JOINTS...............................................................................................................21

3.3. CHECKING MEMBERS SUBJECT TO CRIPPLING ......................................................... 23

3.4. CHECKING MEMBERS SUBJECT TO BUCKLING.......................................................... 24

3.5. CASE OF STRUCTURES SUBJECTED TO SIGNIFICANT DEFORMATION .................. 25



3.6. CHECKING MEMBERS SUBJECTED TO FATIGUE........................................................ 26

3.6.1. CONVENTIONAL NUMBER OF CYCLES AND STRESS SPECTRUM ...................... 26

3.6.2. MATERIAL USED AND NOTCH EFFECT ................................................................... 26

3.6.3. DETERMINATION OF THE MAXIMUM STRESS σmax ................................................ 26

3.6.4. THE RATIO κ BETWEEN THE EXTREME STRESSES.............................................. 27

3.6.5. CHECKING MEMBERS SUBJECTED TO FATIGUE .................................................. 27

.APPENDIX ............................................................................................................................... 28

A - 3.2.2.2.2.3. DESIGN OF JOINTS USING HIGH STRENGTH BOLTS WITHCONTROLLED TIGHTENING ............................................................................................... 28

A- 3.2.2.3. - STRESSES IN WELDED JOINTS...................................................................... 32

A - 3.3. - CHECKING STRUCTURAL MEMBERS SUBJECT TO CRIPPLING...................... 34

A - 3.6. - CHECKING STRUCTURAL MEMBERS SUBJECT TO FATIGUE.......................... 461 - VERIFICATION OF STRUCTURAL MEMBERS..........................................................................472 - VERIFICATION OF THE JOINING MEANS (welds, bolts, rivets).................................................54

EXAMPLES OF CALCULATING CHECKS.............................................................................. 67

EXAMPLES OF FATIGUE CHECKS FOR A WELDED WEB TO FLANGE JOINT STEELSt 37....................................................................................................................................... 67

CHECKING FOR FATIGUE AND ELASTIC LIMIT................................................................. 68FIRST EXAMPLE - COMPONENT IN GROUP E4 WITH FILLET WELD (O Q )................................68SECOND EXAMPLE - COMPONENT IN GROUP E6 - K WELD (S.Q.) ............................................71



INTRODUCTION

The stresses set up in the various structural members are determined for the three cases ofloading defined under section 2.3., and a check is made to ensure that there is a sufficientsafety coefficient ν in respect of the critical stresses, considering the following three possiblecauses of failure :

- exceeding the elastic limit ;

- exceeding the critical crippling or buckling load ;

- exceeding the limit of endurance to fatigue.

The quality of the steels used must be stated and the physical properties, chemical compositionand welding qualities must be guaranteed by the manufacturer of the material.

The permissible stresses for the materials used are determined as stipulated in clauses 3.2.,3.3., 3.4. and 3.6. thereunder, with reference to the critical stresses for the material.

These critical stresses are those which correspond either to the elastic limit (which in practice,involves establishing the stress corresponding to a critical limit for elongation), or to the criticalstress for crippling or buckling, or, in the case of fatigue, to the stress for which the probability ofsurvival, under tests, is 90 %.

The stresses in the structural members shall be calculated on the basis of the different cases ofloading envisaged under section 2.3. by applying conventional strength of materials calculationprocedures.

The sections of metal to be considered shall be the gross sections (i.e. without deducting theareas of holes) for all parts which are subjected to compression loads 1, and the net sections(i.e. with the areas of holes deducted) for all parts subjected to tensile loads.

In the case of a member subjected to bending, a half-net section should be assumed, taking thenet section in parts under tension and the gross section in parts under compression. To simplifythe calculations, however, one may use either the section modulus of the net section or thesection modulus computed for the half-net section, using as centre of gravity of the section thatof the gross section.

1 The area of the holes shall be included in the cross-sectional area only when they are filled by a rivetor a bolt.



3.1. THE CHOICE OF STEEL QUALITIES

The verifications required in the design rules for the safety of the structure against yielding,instability and fatigue failure do not guarantee safety against brittle fracture.

In order to obtain sufficient safety against brittle fracture, a steel quality has to be chosendepending on the conditions influencing brittle fracture.

The most important influences on the sensitivity to brittle fracture in steel structures are :

A. Combined effect of longitudinal residual tensile stresses with tensile stresses from deadload.

B. Thickness of the member.

C. Influence of cold.

Influences A, B, and C are valued with points. The required steel quality depends on the sum ofthese points.

3.1.1. ASSESSMENT OF THE FACTORS WHICH INFLUENCE BRITTLE FRACTURE

In the following, influences A, B, and C in paragraph 3.1. are described and quantified.

3.1.1.1. INFLUENCE A : COMBINED EFFECT OF LONGITUDINAL RESIDUAL TENSILESTRESSES WITH STRESSES FROM DEAD WEIGHT

σa = permissible tensile stress with respectto the elastic limit, loading case I.

σG = tensile stress from permanent load,e.g. from dead weight

ZA = assessing coefficient for influence A

Equations for lines I, II and III in figure 3.1.1.1.

Line I : no welds, or only transverse weldsZA = σG / ( 0,5 . σa ) - 1

valid only for σG ≥ 0,5 . σa

Line II : longitudinal welds

ZA = σG / ( 0,5 . σa )

Line III : accumulation of welds

ZA = σG / ( 0,5 . σa ) + 1



The danger of brittle fracture is increased by high stress concentrations, in particular by3-axial tensile stresses, as is the case with an accumulation of welds.If members with low-stresses are stress relieved after welding (approx. 600-650° C) line I canbe used for all types of welds.

Assessing coefficient

I : No welds or only tranverse welds II : Longitudinal weldsIII : Weld accumulation

Figure 3.1.1.1. - ZA in terms of stresses and welds



3.1.1.2. INFLUENCE B : THICKNESS OF MEMBER t

t = Thickness of member in mm

ZB = Assessing coefficient for influence B

from t = 5 to t = 20 mmZB = 9 . t2 / 2500.

from t = 20 to t = 100 mmZB = 0,65 . ( t - 14,81 )0,5 -0,05

Thickness of member

Figure 3.1.1.2. - Assessing coefficient ZB = f (t)

tmm

ZB tmm

ZB tmm

ZB

56789

101215

0,100,150,200,250,300,400,500,80

162025303540455055

0,91,452,02,52,93,23,53,84,0

6065707580859095100

4,34,554,85,05,25,45,65,86,0

For rolled sections an idealised thickness t* is to be used. This is :

for round sections : t* = d / 1,8

for square sections : t* = t / 1,8

for rectangular sections : t* = b / 1,8

where b represents the larger side of the rectangle and the ratio of the sides b / t ≤ 1,8

For b / t > 1,8 then t* = t.



3.1.1.3. INFLUENCE C : INFLUENCE OF COLD

The lowest temperature at the place of erection of the crane determines the classification. Thistemperature is generally lower than the working temperature.

T = Temperature at the place of erection in °C

ZC = Assessing coefft. for influence C

from T = 0°C to T = - 30°C take

ZC = 6 . T2 / 1600

from T = - 30°C to T = - 55°C take

ZC = [ ( - 2,25 . T ) -33,75 ] / 10

Ten ° C

ZC Ten ° C

ZC

0- 5

- 10- 15- 20- 25

0,00,10,40,81,52,3

- 30- 35- 40- 45- 50- 55

3,44,55,66,77,99,0

Temperature T in °C

Figure 3.1.1.3. - Assessing coefft. ZC = f (T)

3.1.2. DETERMINATION OF THE REQUIRED STEEL QUALITY GROUP

It is the sum of assessing coefficients from paragraph 3.1.1. which determines the minimumrequired quality for the steel structure.

Table T. 3.1.2. shows the classification of the quality group in relation to the sum of theassessing coefficients.

If the sum of the assessing coefficients is higher than 16 or if the required steel quality cannotbe obtained, special measures will be necessary to obtain the steel quality necessary for safetyagainst brittle fracture which will have to be determined with material experts.



Table T.3.1.2.Classification of quality groups in relation to the sum of the assessing coefficients

Sum of the assessing coefficientsfrom paragraph 3.1.1.ΣZ = ZA + ZB + ZC

Quality group correspondingin table T.3.1.3

≤ 2

≤ 4

≤ 8

≤ 16

1

2

3

4

3.1.3. QUALITY OF STEELS

The quality of steels in these design rules is the property of steel to exhibit a ductile behaviourat determined temperatures.

The steels are divided into four quality groups. The group in which the steel is classified, isobtained from its notch ductility in a given test and temperature.

Table T.3.1.3. comprises the notch ductility values and test temperatures for the four qualitygroups.

The indicated notch ductilities are minimum values, being the mean values from three tests,where no value must be below 20 Nm/cm2.

The notch ductility is to be determined in accordance with V-notch impact tests to ISO R 148and Euronorm 45-63.

Steels of different quality groups can be welded together.

TC is the test temperature for the V-notch impact test.

T is the temperature at the place of erection of the crane.

TC and T are not directly comparable as the V-notch impact test imposes a more unfavourablecondition than the loading on the crane in or out of service.



Table T.3.1.3. - Quality groups

Qualitygroup

Notch ductilitymeasured in

ISO sharp notchtest ISO R 148

in Nm/cm2

Test temperature

Tc °C

Steels, correspondingto the quality group

Designation of steels

Standard

Fe 360 - AFe 430 - A

Euronorm 25

1 - -St 37 - 2St 44 - 2

DIN 17100

E 24 - 1 NF A 35-50143 A 50 B * BS 4360 1972Fe 360 - BFe 430 - BFe 510 - B

Euronorm 25

2 35 + 20R St 37-2St 44-2

DIN 17100

E 24 (A37) - 2E 26 (A42) - 2E 36 (A52) - 2

NF A 35-501

40 B 43 B * BS 4360 1972Fe 360 - CFe 430 - CFe 510 - C

Euronorm 25

3 35 0

St 37 - 3USt 44 - 3USt 52 - 3U

DIN 17100

E 24 (A37) - 3E 26 (A42) - 3E 36 (A52) - 3

NF A 35-501

40 C 43 C *50 C 55 C

BS 4360 1972

Fe 360 - DFe 410 - DFe 510 - D

Euronorm 25

4 35 -20

St 37 - 3NSt 44 - 3NSt 52 - 3N

DIN 17100

E 24 (A37) - 4E 26 (A42) - 4E 36 (A52) - 4

NF A 35-501

40 D 43 D *50 D 55 E

BS 4360 1972

* The test requirements of steels to BS.4360 do not in all cases agree with the Euronorm andother national standards, and the guaranteed impact test properties for steels to BS.4360 maybe different to other steels in the same quality group. Impact test properties are stated in BS.4360 and where the requirements are different from those guaranteed in BS. 4360, agreementmust be obtained from the steel suppliers.



3.1.4. SPECIAL RULES

In addition to the above provisions for the choice of the steel quality, the following rules are tobe observed :

1 - Non killed steels of group 1 shall be used for load carrying structures only in case of rolledsections and tubes not exceeding 6 mm thickness.

2 - Members of more than 50 mm thickness, shall not be used for welded load carryingstructures unless the manufacturer has a comprehensive experience in the welding ofthick plates. The steel quality and its testing has in this case to be determined byspecialists.

3 - If parts are cold bent with a radius/plate thickness ratio < 10 the steel quality has to besuitable for folding or cold flanging.



3.2. CHECKING WITH RESPECT TO THE ELASTIC LIMIT

For this check, a distinction is made between the actual members of the structure and theriveted, bolted or welded joints.

3.2.1. STRUCTURAL MEMBERS OTHER THAN JOINTS

3.2.1.1. MEMBERS SUBJECTED TO SIMPLE TENSION OR COMPRESSION

1) Case of steels for which the ratio between the elastic limit σE and the ultimate tensile strengthσR is < 0,7.

The computed stress σ must not exceed the maximum permissible stress σa obtained bydividing the elastic limit stress σE by a coefficient νE which depends upon the case of loading asdefined under section 2.3.

The values of νE and the permissible stresses are :

Values of νE Case I1,5

Case II1,33

Case III1,1

Permissible stresses σa σE / 1,5 σE / 1,33 σE / 1,1

For carbon steels of current manufacture A.37 - A.42 - A.52 (also called E.24 - E.26 - E.36 or Fe360 - Fe 510) the critical stress σE is conventionally taken as that which corresponds to anelongation of 0,2 %.

Table T.3.2.1.1. - Values of σσσσE and σσσσa for steels A.37 - A.42 - A.52

Elastic limit Maximum permissible stresses : σa

STEELS σE Case I Case II Case IIIN/mm2 N/mm2 N/mm2 N/mm2

E.24 (A.37, Fe 360)

E 26 (A.42)

E.36 (A.52, Fe 510)

240

260

360

160

175

240

180

195

270

215

240

325



2) Case of steels with high elastic limit ( σE / σR > 0,7)

For steels with high elastic limit where the ratio σE / σR is greater than 0.7, the use of the νE

coefficients does not ensure a sufficient margin of safety. In this case a check can be made thatthe permissible stress σa given by the formula below is not exceeded :

σa = [ (σE + σR ) / (σE.52 + σR.52 ) ] . σa 52

where :

σE and σR are the elastic limit and the ultimate tensile strength of the steel considered

σE.52 and σR.52 these same stresses for steel A.52, i.e. 360 N/mm2 and 510 N/mm2

σa 52 the permissible stress for steel A.52 in the case of loading considered.

3.2.1.2. MEMBERS SUBJECTED TO SHEAR

The permissible stress in shear τa has the following value :

τa = σa / 3 0,5

σa being the permissible tensile stress.

3.2.1.3. MEMBERS SUBJECTED TO COMBINED LOADS - EQUIVALENT STRESS

σx , σy and τxy being respectively the two normal stresses and the shear stress at a given point,a check shall be made :

1 - that each of the two stresses σx and σy is less than σa and that τxy is less than τa

2 - that the equivalent stress σcp is less than σa, i.e. :

σcp = ( σx2 + σy

2 - σx . σy + 3 . τxy2 ) 0,5 ≤ σa

When using this formula, a simple method is to take the maximum values σx , σy and τxy. But, infact, such a calculation leads to too great an equivalent stress if it is impossible for themaximum values of each of the three stresses to occur simultaneously.

Nevertheless, the simple calculation method, being conservative, is always acceptable.

If it is desired to calculate more precisely, it is necessary to determine the most unfavourablepractical combination that may occur. Three checks must then be made by calculatingsuccessively the equivalent stress resulting from the three following combinations :

σx max and the corresponding stresses σy and τxy

σy max and the corresponding stresses σx and τxy

τxy maw and the corresponding stresses σx and σy



Note : It should be noted that when two out of the three stresses are approximately of the samevalue, and greater than half the permissible stress, the most unfavourable combination of thethree values may occur in different loading cases from those corresponding to the maximum ofeach of the three stresses.

Special case :

- Tension (or compression) combined with shear

The following formula should be checked :

( σ2 + 3 . τ2 )0,5 ≤ σa

3.2.2. CASE OF JOINTS

3.2.2.1 RIVETED JOINTS

1 - Rivets in shear

Taking the effect of the clamping force into account, the calculated shearing stress τ must notexceed :

τ = 0,6 . σa in the case of single shearand

τ = 0,8 . σa in the case of double or multiple shear

where σa is the permissible tensile stress of the metal used for the rivet.

single shear double or multiple shear

2 - Rivets in tension

The calculated tensile stress σ must not exceed the value :σ = 0,2 . σa



3 - Rivets loaded in tension and shear

The following conditions must be checked : σ ≤ 0,2 . σa

and τ ≤ 0,6 . σa for single shearor τ ≤ 0,8 . σa for double shear

4 - Limit of bearing pressure

The bearing pressure in the walls of holes σn must not exceed :σn ≤ 1,5 . σa for single shearσn ≤ 2 . σa for double shear

5 - Notes concerning riveted joints

a) Rivets subjected to tension should be avoided, particularly for the main members ;

b) all joints must have at least two rivets aligned in the direction of the force.

3.2.2.2. BOLTED JOINTS

3.2.2.2.0. GENERAL

Bolted joints may be subjected to stresses due to forces acting perpendicular to the joint (jointsby tension bolts), due to forces acting parallel to the joint surfaces, and due to forces actingsimultaneously perpendicular and parallel to the joint surface.

3.2.2.2.1. JOINTS MADE WITH TENSION BOLTS WITH CONTROLLED TIGHTENING

1 - General

A joint by tension bolts with controlled tightening is a joint in which the main tension is in thedirection of the axis of the bolt, screw or threaded rod and which has been subject to atightening effect, applied in the absence of any external load, which is recommended for alljoints subjected to fatigue.

Care must be taken to ensure that the bolt is not subjected to shear loading. These bolts do notcome into the category of H.S. bolts but may be used if they fulfil the conditions of 3.2.2.2.2.3.

Care should be taken to ensure that the bolts are correctly tightened and that the tightening ispermanent (tolerance +/- 10 %). Factor Ω = 1,1 is introduced to take account of tolerances.

During the application of the initial tightening on the bolt, under the combined effect of tensionand torsional loading the stress should not exceed 80 % of the elastic limit, taking account ofthe scatter in applying the initial tightening.



2 - Calculation of the permissible load on joints

A - Calculation of the initial tightening force to be used

a) Tightening with twistσb = (σp

2 + 3 . τb2 )0,5 ≤ 0,8 σE

τb = [ ( 2 . d2 . σp ) / dt ] . [ pa / ( π . d2 ) + 1,155 . µ]where :σp = theoretical tensile stress under the tightening effectτb = torsional stress under the tightening effectd2 = diameter of the root of the threaddt = nominal diameter of the boltpa = thread pitchµ = friction coefficient in the threadsσE = elastic limit of the bolt metal

b) Tightening without twist σb ≤ 0,8 σE

B - Permissible load F1 on the joint

Two checks are to be made :

a) Under the maximum load, taking into account the safety coefficient κ and κ‘, the elastic limitof the bolt must not be exceeded.

determine : σ‘1 = ( σb2 - 3 . τb

2 )0,5

check that : F1 / Sb ≤ ( σ‘1 - σp ) / ( κ . κ‘ . δb ) where :

Sb = section of the root < section of the shank.

δb = ∆l1 / (∆l1 + ∆l2 )

∆l1 = shortening of the elements to be tightened under the action of the tightening force

∆l2 = lengthening of bolt under the action of the tightening force.

For assembled steel parts, the section to be considered for ∆l1 :

Seq = 0,25 . π . [ ( S1 + 0,1 . lk )2 - Dt

2 ]where :

S1 = bearing diameter under head

lk = length of tightened parts

Dt = diameter of bolt holes



For bolts whose shank diameter differs considerably from the root diameter of the thread andwhere there is an appreciable threaded length remaining in the part submitted to stress, acomplete calculation of ∆l2 should be made.

b) Under the maximum load with application of coefficients Ω, κ' and κ " separation of the partsshould not occur.

σ1 = F1 / Sb ≤ σp / [ κ' . κ'‘ . ( 1 - δb ) . Ω ]

Safety coefficients κ , κ' and κ'‘

κ depends on the surface state of the parts to be tightened (machined surface κ = 1 )

κ' corresponds to safety in relation to the elastic limit in accordance with table T.3.2.2.2.

κ'' corresponds to safety against separation of the parts.

Table T.3.2.2.2.

Case I Case II Case III

κ‘ 1,50 1,33 1,1

κ‘’ 1,3 1,0 1,0

Note : The coefficients κ‘ and κ‘’ should be applied to the most unfavourable condition arisingfrom the scatter in applying the initial tightening effort.

C - Checking for fatigue

Checking bolts for fatigue is carried out solely for case I loads.

Under the effect of the service load F1, the true tensile stress varies between the values :

σp and σp + ( F1 . δb ) / Sb

The following equation must be verified :

σ1 = F1 / Sb ≤ 2 . σA / δb

σA is the amplitude of the maximum permissible stress for fatigue given in the followinggraph.

For any other type of bolt or design method the σA value should ensure at least an equivalentlever of safety against fatigue.

Any conformity tests should be carried out according to ISO specification 3800/1with σm = 0,8 . RE . ( RE = σE )



Amplitude of maximum permissible fatigue stress

Graph for ISO bolts

- standard thread- classes 8.8, 10.9, 12.9- cold rolled thread with heat treatment after rolling



3.2.2.2.2. BOLTED JOINTS SUBJECTED TO FORCES ACTING PARALLEL TO THE JOINT PLANE

1 - Bolts subjected to shear (fitted bolts)

Preferably for non-fluctuating stresses with and without preload.

The following checks presuppose that the bolting has been effected under proper conditions,i.e. using fitted bolts (turned or cold finished) with ISO tolerances and the shanks of whichbear against the full length of holes drilled in the parts being assembled. Holes must bedrilled and reamed with the ISO tolerances.

Black bolts are permitted only for secondary joints which do not transmit heavy loads. Theyare prohibited for joints subject to fatigue.

The calculated stress τ on the shank shall not exceed the values given forrivets in clause 3.2.2.1.1-.

The bearing pressure shall not exceed the values indicated in clause 3.2.2.1.4.

2 - Bolts subjected to combined tension and shear

A check shall be made that :

σ ≤ 0,65 . σa

and τ ≤ 0,6 . σa for single shear

or τ ≤ 0,8 . σa for double shear

and that ( σ2 + 3 . τ2 )0,5 ≤ σa

The permissible stress in a bolt is limited to :

σa = 0,7 . σE(0,2) for normal execution

σa = 0,8 . σE(0,2) for a construction which preventsstripping the thread.

where σE(0,2) is the 0,2 % proof stress of the metal constituting the bolt.



3 - Joints using high strength bolts with controlled tightening (H.S.)

This type of joint is recommended for assemblies subjected to fatigue and whose main loadsare parallel to joint faces. Members joined by H.S. bolts are subjected to the following typesof loads :

A - Loads acting in the plane of the joint (symbol T)

In this case, the loads tend to make the parts in contact slip and the force is transmitted byfriction. To determine the permissible load per bolt Ta which can be transmitted by friction,the tensile force F which exists in the bolt after tightening must be considered. This ismultiplied by the coefficient of friction µ of the contact surfaces, and the safety coefficientsνT which are the same as those in clause (3.2.1.1.) are applied to this limiting force, i.e.

νT = 1,5 for case I loading

= 1,33 for case II loading

= 1,1 for case III loading

This may be expressed : Ta = m . ( µ . F )/ νT

m being the number of friction surfaces.

The tension, F, in a bolt depends upon the tightening torque ; the value of µ depends uponthe metal constituting the members, the state of the surfaces in contact, and the method ofpreparation. Appendix A 3.2.2.2.2.3. gives information on this subject.

B - Forces perpendicular to the plane of the joint (symbol N)

The checking by calculation of the forces perpendicular to the assembly surface shall becarried out in accordance with clause 3.2.2.2.1.

If the bolted joint is subjected to an external couple M, the tensile loading has to bedetermined at the bolt which is subjected to the maximum loading and, where applicable,added to the existing tensile load N.



C - Combined loads of the T, N and M types

Two checks must be made :

a) That, for the most highly stressed bolt, the sum of the tensile forces due to N and Mloadings remains less than the permissible tensile force as defined in 3.2.2.2.2.

b) That the mean load which is transmitted by friction is less than the following value :

T = µ . ( F - N ) . m / νT

D - Determination of the stresses in the members joined

For members subject to compression, the stress is calculated on the gross section (cross -sectional area of the holes not deducted).

For members subjected to tension there are two cases :

1st case : Bolts set in a single row, perpendicular to the direction of the load ; the followingconditions must be checked :

a) the total load on the gross section

b) 60 % of the total load on the net section (cross-sectional area of holes deducted)

2nd case : Several rows of bolts perpendicular to the direction of the load.

The most heavily loaded section (corresponding torow 1 for the member A - see figure) must beanalysed and the following two conditions checked :

a) the total load on the gross section, and

b) on the net section, the total load from rows 2 and 3 (i.e. in the case of the figure, 2/3 ofthe total load of the joint) to which 60 % of the load taken by row 1 is added.

This assumes that the load is equally divided amongst all the bolts and that the number ofrows of bolts is small because if there are too many, the last bolts carry little load. It istherefore recommended that not more than two rows of bolts should be used orexceptionally three.



E - Execution of joints with high-strength bolts

It must be emphasised that the above calculations to check the adequacy of joints withhigh strength bolts are valid only for joints made in accordance with accepted practicewhich requires controlled tightening of the bolts and preparation of the contact surfaces toobtain suitable coefficients of friction.

See appendix A - 3.2.2.2.2.3. for further guidance.

3.2.2.3. WELDED JOINTS

In welded joints, it is assumed that the deposited metal has at least as good characteristics asthe parent metal.

It must be verified that the stresses developed, in the cases of longitudinal tension andcompression, do not exceed the permissible stresses σa given in clause 3.2.1.1.For shear in the welds, the permissible stress τa is given by :

τa = σa / 20,5

However, for certain types of loading, particularly transverse stresses in the welds, themaximum permissible equivalent stress is reduced.

Table T. 3.2.2.3. summarises the values not to be exceeded, for certain steels, according to thetype of loading.



Table T. 3.2.2.3. - Maximum permissible equivalent stresses in welds(N/mm2) : steels A.37 (Fe 360) - A.42 - A.52 (Fe 510)

Types of loading A.37 A.42 A.52Case I Case II Case

IIICase I Case II Case

IIICase I Case II Case

III

Longitudinal equivalent

stresses for all types

of welds

160 180 215 175 195 240 240 270 325

Transverse tensile

stresses

1) Butt-welds andspecial

quality K welds

2) Ordinary quality K-welds

3) Fillet welds

160

140

113

180

158

127

215

185

152

175

153

124

195

170

138

240

210

170

240

210

170

270

236

191

325

285

230

Transverse compressive

stresses

1) Butt-welds and Kwelds

2) Fillet welds

160

130

180

146

215

175

175

142

195

158

240

195

240

195

270

220

325

265

ShearAll tapes of welds

113 127 152, 124 138 170 170 191 230

Appendix A-3.2.2.3. gives some additional information on welded joints.



3.3. CHECKING MEMBERS SUBJECT TO CRIPPLING

The guiding principle shall be that parts subject to crippling must be designed with the samesafety margin as that adopted in respect of the elastic limit ; in other words, having determinedthe practical crippling stress, the maximum permissible stress shall be the crippling stressdivided by the appropriate coefficient 1,5 or 1,33 or 1,1 specified in 3.2.1.1.

The choice of a practical method of calculation is left to the manufacturer who must state theorigin of the method chosen.

If the method chosen involves multiplying the computed stress by a crippling coefficient ωdepending upon the slenderness ratio of the member and then checking that this amplifiedstress remains less than a certain allowable stress, the value to be chosen for this allowablestress shall be as specified in 3.2.1.1.

Note : Appendix A-3.3. shows how to apply various classical methods of calculation inaccordance with the above requirements.



3.4. CHECKING MEMBERS SUBJECT TO BUCKLING

In determining the new buckling safety coefficients, stated below, it was considered that flatplates under compressive stresses equally distributed over the plate width, are exposed to agreater danger of buckling than plates under stresses changing from compression to tensionover the plate width.

In consequence, safety against buckling was made dependent on the ratio ψ of stresses at theplate edges (appendix A-3.4.)

In addition it was found necessary to determine the critical buckling stress for circular cylindersand the spacing and moment of inertia of the transverse stiffeners in order to avoid too greatdivergences in the effective safety due to the use of highly divergent data in technical literature.

It shall be verified that the calculated stress is not higher than the critical buckling stress dividedby the following coefficients νV :

Case Buckling safety νV

Buckling of plane members IIIIII

1,70 + 0,175 ( ψ - 1)1,50 + 0,125 (ψ - 1)1,35 + 0,075 (ψ - 1)

Buckling of curved members ;Circular cylinders(e.g. tubes)

IIIIII

1,701,501,35

The edge-stresses ratio ψ varies between + 1 and - 1.

Appendix A.3.4. gives the procedure for determining the critical buckling stress.



3.5. CASE OF STRUCTURES SUBJECTED TO SIGNIFICANTDEFORMATION

In this case the stresses in the members may not be proportional to the forces which causethem due to the deformation of the structure as a result of the application of these forces.

This is the case, for exempla, with the stresses produced in thecolumn of a crane (illustrated diagrammatically) where it is clear thatthe moment in the column is not proportional to the forces appliedbecause of deformations which increase their moment arm.

In this case the calculation is made as follows :

1 - First make the checks required by clauses 3.2. - 3.3. - 3.4.calculating the stresses resulting from the various cases of loadingand checking that there is a sufficient safety margin in relation to thecritical stresses (elastic limit, crippling, buckling). In the calculation ofthe stresses account is taken of the deformation due to the loads onthe structure.

2 - A further check is also carried out by calculating the stresses resulting from the application ofthe loads multiplied by the coefficient ν of the case of loading considered and taking intoaccount the deformations resulting from the application of these increased loads and checkingthat the stresses thus calculated remain less than the critical stresses for the elastic limit, forcrippling and for buckling.However, to take account of the fact that the variable loads Sv (loads due to the hoisted loadmultiplied by ψ, to the wind and to horizontal movements) are more dangerous than theconstant load due to the dead weight SG, a check can be made in practice by considering twocases as follows :

1 - When the effects of the dead weight SG and of the variable load Sv lead to deformation inopposite directions :Determine the stress σG resulting from the application of the dead weight SG (withoutamplification) and σv resulting from the variable loads SV, multiplied by the coefficient νcorresponding to the case considered (clause 3.2. elastic limit, 3.3. crippling, 3.4. buckling) andcheck that this stress is less than the critical value i.e. :

σ resulting from ( SG + ν . Sv ) ≤ σcr

2 - when the dead weight and the variable load lead to deformations in the same direction :determine the stress resulting from the application of the variable load multiplied by thecoefficient ν and of the dead weight multiplied by the coefficient :

ν‘ = 1 + ( ν - 1 ) . rwhere r = σG / (σG + σV ) calculated in the initial stage of the deformations.We then have : σ resulting from (ν' . SG + ν . Sv ) ≤ σcr



3.6. CHECKING MEMBERS SUBJECTED TO FATIGUE

Danger of fatigue occurs when a member is subjected to varying and repeated loads.

Fatigue strength is calculated by considering the following parameters :

1 - the conventional number of cycles and the stress spectrum to which the member issubjected ;

2 - the material used and the notch effect at the point being considered ;

3 - the extreme maximum stress σmax which can occur in the member ;

4 - the ratio κ between the values of the extreme stresses.

3.6.1. CONVENTIONAL NUMBER OF CYCLES AND STRESS SPECTRUM

The number of cycles of variations of loading and the spectrum of stresses to be taken intoconsideration are discussed in clause 2.1.2.2. and in clause 2.1.2.3.

These two parameters are taken into account when considering solely the group in which themember is classified in accordance with clause 2.1.4.

3.6.2. MATERIAL USED AND NOTCH EFFECT

The fatigue strength of a member depends upon the quality of the material used and upon theshape and the method of making the joints. The shapes of the parts joined and the means ofdoing it have the effect of producing stress concentrations (or notch effects) which considerablyreduce the fatigue strength of the member.

Appendix A-3.6. gives a classification of various joints according to their degree of stressconcentration (or notch effect).

3.6.3. DETERMINATION OF THE MAXIMUM STRESS σσσσmax

The maximum stress, σmax is the highest stress in absolute value (i.e. it may be tension orcompression) which occurs in the member in loading case I referred to in clause 2.3.1. withoutthe application of the amplifying coefficient γC

When checking members in compression for fatigue the crippling coefficient, ω given in clause3.3. should not be applied.



3.6.4. THE RATIO κκκκ BETWEEN THE EXTREME STRESSES

This ratio is determined by calculating the extreme values of the stresses to which thecomponent is subjected under case I loadings.

The ratio may vary depending upon the operating cycles but it errs on the safe side todetermine this ratio κ by taking the two extreme values which can occur during possibleoperations under case I loadings.

If cmax and cmin are the algebraic values of these extreme stresses, cmax being the extremestress having the higher absolute value, the ratio κ may be written :

κ = σmin / σmax or τmin / τmax in the case of shear.

This ratio, which varies from + 1 to - 1, is positive if the extreme stresses are both of the samesense (fluctuating stresses) and negative when the extreme stresses are of opposite sense(alternating stresses).

3.6.5. CHECKING MEMBERS SUBJECTED TO FATIGUE

Using the parameters defined in clauses 3.6.1. to 3.6.4. the adequacy of the structural membersand of the joints subjected to fatigue is ensured by checking that the stress σmax , as defined inclause 3.6.3. is not greater than the permissible stress for fatigue of the members underconsideration.

This permissible stress for fatigue is derived from the critical stress, defined as being the stresswhich, on the basis of tests made with test pieces, corresponds to a 90 % probability of survivalto which a coefficient of safety of 4/3 is applied thus :

σa for fatigue = 0,75 . c at 90 % survival.

The determination of these permissible stresses having regard to all these considerations is acomplex problem and it is generally advisable to refer to specialised books on the subject.

Appendix A-3.6. gives practical indications, based on the results of research in this field, on thedetermination of permissible stresses for A.37 - A.42 and A.52 steels, according to the variousgroups in which the components are classified, and the notch effects of the main types of jointsused in the manufacture of hoisting appliances.



.APPENDIX

A - 3.2.2.2.2.3. DESIGN OF JOINTS USING HIGH STRENGTH BOLTS WITHCONTROLLED TIGHTENING

Clause 3.2.2.2.2.3. determines the general requirements to be observed for the execution ofjoints with high strength bolts.

This appendix gives some directions on the preparation of the surfaces to be joined, the frictioncoefficients obtained and the tightening methods.

Coefficient of friction µ

The coefficient of friction used for the calculation of the force transmitted by friction dependsupon the joined material and upon the preparation of the surfaces.

A minimum preparation before jointing will consist in removing every trace of dust, rust, oil andpaint by energetic brushing with a clean metallic brush. Oil stains must be removed by flamecleaning or by the application of suitable chemical products (carbon tetrachloride, for instance).

A more careful preparation will increase the coefficient of friction. This could be sandblasting,shotblasting or oxy-acetylene flame cleaning clone not more than five hours before tightening ;brushing must be alone just prior to jointing.

The coefficients of friction are given in the following table.

Table T.A.3.2.2.2.2.3.1. - Values of µµµµ

Joined material Normally prepared surfaces(degreasing and brushing)

Specially prepared surfaces(flame-cleaned, shot or

sand-blasted)

E-24 (A.37) Fe 360

E-26 (A.42)

E-36 (A.52) Fe 510

0,30

0,30

0,30

0,50

0,50

0,55

It is necessary to insert two washers, one under the boit head, the other under the nut. Thesewashers must have a 45° bevel, at least on the internal rim, and turned towards the boit head orthe nut. They must be heat-treated in order that their hardness shall be at least equal to that ofthe metal constituting the boit



Bolt tighteninq

The value of the tension induced in the bolt must reach the value determined by calculation.

This tension, resulting from tightening, can be measured by calculation of the torque to beapplied to the boit and given by the formula :

Ma = 1,10 . C . d .F

where :

Ma is the torque to be applied in Nm

d is the nominal diameter of the bolt in mm

F is the nominal tension to be induced in the bolt (kN)

C is a coefficient depending on the thread form,the friction coefficient or the threads andbetween the nut and the washer.

With metric-threaded bolts and washers as delivered (slightly oiled, without rust or dust) :

C = 0,18

The tensile stress in the boit must not exceed that defined under clause 3.2.2.2.2.

Value of the tensile stress area of the bolts

When determining the stress in the bolt, the tensile stress area shall be calculated by taking thearithmetic mean of the core (minor) diameter and the effective thread diameter. These valuesare given in the following table :

Nominaldiameter( mm )

8 10 12 14 16 18 20 22 24 27 30

Tensilestress area( mm2 )

36,6 58 84,3 115 157 192 245 303 353 459 561



Qualitv of the bolts

Bolts used for this type of joint have a high elastic limit.The ultimate tensile strength σR must be greater than the values given hereunder :

σE 0,2

N/mm2σR

N/mm2

< 700 > 1,15 . σE

700 to 850 > 1,12 . σE

> 850 > 1,10 . σE

The diameter of holes shall not exceed by more than 2 mm the diameter of the bolt.

The following table gives per bolt and per friction surface, the values of the transmissible forcesin the plane parallel to that of the joint for bolts of 1000 - 1200 N/mm2 with an elastic limit of σE =90O N/mm2 for various friction coefficients for the steels A. 37, A.42 and A. 52.

To apply these figures, the number of effective friction surfaces as indicated in the drawingbelow must be determined.

1 friction surface m = 1

2 friction surfaces m = 2

3 friction surfaces m = 3

Effective friction surfaces



Table T.A.3.2.2.2.2.3.2.Transmissible forces in the plane of the joint per bolt and per friction surface

Bolts of 1000/1200 N/mm2 : σE = 90O N/mm2

with means of preventing stripping of the threads : σa = 0,8 . σE

Bolt- Ten-Normally prepared

surfacesSpecially prepared surfaces

dia-me-ter

silestressarea

Clam-pingforce

Appliedtorque

SteelsA-37, A-42, A-52

µ = 0,30

SteelsA-37, A-42µ = 0,50

SteelA-52

µ = 0,55

mm mm2 kN NmCase

IkN

CaseII

kN

CaseIIIkN

CaseI

kN

CaseII

kN

CaseIIIkN

CaseI

kN

CaseII

kN

CaseIIIkN

10

12

14

16

18

20

22

24

27

58

84,3

115

157

192

245

303

353

459

41,7

60,6

82,7

113,0

138,0

176,0

218,0

254,0

330,0

82,7

144,0

229,0

358,0

492,0

697,0

950,0

1200,0

1760,0

8,3

12,1

16,5

22,6

27,6

35,2

43,6

50,8

66,0

9,4

13,6

18,6

25,5

31,0

39,7

49,3

57,1

74,2

11,4

16,5

22,5

30,8

37,6

48,0

59,7

69,4

90,0

13,9

20,2

27,5

37,7

46,0

58,5

72,5

84,5

110,0

15,7

22,8

31,0

42,5

51,8

66,1

82,0

95,5

124,0

18,9

27,5

37,6

51,4

62,7

80,0

99,0

115,5

150,0

15,2

22,2

30,2

41,5

50,6

64,5

80,0

93,1

121,0

17,2

25,0

34,2

46,8

57,0

72,7

90,2

105,0

136,0

20,8

30,3

41,4

56,5

69,0

88,0

109,0

127,0

165,0

For a bolt with an elastic limit of σE’ the values of the forces and of the torques indicated in thistable are to be multiplied by the ratio σE /9oo.

Where no special measures are taken to avoid stripping of the threads ( σa = 0,7 . σE ) thesevalues are to be divided by 1,14.



A- 3.2.2.3. - STRESSES IN WELDED JOINTS

Determining the stresses in welds is a highly complex problem primarily because of the greatnumber of possible configurations welded joints can assume.

For this reason it is not possible, as the master stands at present, to lay clown precise directivesin these Rules for the Design of Hoisting Appliances. Indeed, both the volume and the subjectmaster of rules relating to welding would be difficult to fit into the general context of the presentdesign rules. It was consequently decided to include only the following general indications :

1 - All methods of calculation assume of necessity a properly executed joint, i. e. a weld withcorrect penetration and a good shape, so that the joint between the components to beassembled and the weld seam is free from discontinuity or sudden change of section as wellas from craters or notches due to undercutting.

The design of the weld must be adapted to the forces to be transmitted, and specialisedliterature on the subject should be consulted.

It should be noted that the strength of a welded joint is significantly improved if the surface ofthe weld is finished by careful grinding.

2 - There is no need to take into consideration stress concentrations due to the design of thejoint or residual stresses.

3 - The permissible stresses in welds are those determined under clause 3.2.2.3. and theequivalent stress σcp in the case of combined stresses (tensile or compressive) σ and shearstress τ is given by the formula :

σcp = ( σ2 + 2 . τ2 )0,5

In cases involving dual stresses σx and σy and the shearing stress τxy the following formula isapplied :

σcp = ( σx2 + σy

2 - σx . σy + 2 . τxy2 )0,5

4 - In a fillet weld, the width of the section considered is the depth of the weld to the bottom ofthe throat and its length is the effective length of the weld less the end craters.

The length need not be reduced if the joint closes on to itself or if special precautions aretaken to limit the effect of the craters.

Attention is drawn to the fact that it seems to be reliably established that fatigue failures inwelded joints seldom occur in the weld seam itself but usually beside it in the parent metal.



The stresses σmin and σmax for the fatigue strength calculations for the parent metal besidethe weld seam, can therefore in general be computed using the classical methods forcalculating the strength of meterials.

In order to verify the fatigue strength of the weld itself, it is generally held that it suffices toconfirm that it is capable of transmitting the same loads as the adjacent parent metal.

This rule is not obligatory however when the parts jointed are generously dimensioned inrelation to the forces actually transmitted. When this is the case it suffices to dimension theweld seam in accordance with those forces, with the proviso that a fatigue check should thenbe performed in accordance with appendix A-3.6.

Whatever the case it is emphasised that the size of a weld should invariably be in proportionto the thickness of the assembled parts.

Special cases

In certain cases of assembly by welding, particularly when there is a transverse load (i.e.perpendicular to the weld seam), the permissible stresses must be reduced (see clause3.2.2.3.).



A - 3.3. AND A - 3.4. - CHECKING STRUCTURAL MEMBERS SUBJECT TO CRIPPLINGAND BUCKLING

The aim of these two appendices is not to adopt any specific stand on the problem but merely togive some general indications and enable reference to be made to existing works.

A number of different methods are at present in use, among which the following are cited :

1 - in Germany, DIN 41142 - in Belgium, regulation NBN 13 - in France, the CM 1966 Rules4 - in the United Kingdom, BS 2573.

A - 3.3. - CHECKING STRUCTURAL MEMBERS SUBJECT TO CRIPPLING

While not wishing to adopt any particular standpoint on this problem, the FEM recommends theuse of a practical method in the simpler cases, consisting in amplifying the calculated stress inthe various loading cases defined in clauses 2.3.1., 2.3.2., and 2.3.3., by a crippling coefficientω dependent upon the slenderness ratio of the member, and checking that, in each of thesecases, the stress thus augmented remains less than the stresses given in table T.3.2.1.1.

The values of ω are given in the tables below for the following cases, as a function of theslenderness ratio λ :

Table T.A.3.3.1. : rolled sections in St 37 steel (Fe 360)

Table T.A.3.3.2. : rolled sections in St 52 steel (Fe 510)

Table T.A.3.3.3. : tubes in St 37 steel (Fe 360)

Table T.A.3.3.4. : tubes in St 52 steel (Fe 510)

Determination of effective lengths for calculating the slenderness ratio λ

1 - In the ordinary case of bars hinged at both ends and loaded axially, the effective length istaken as the length between points of articulation.

2 - For an axially loaded bar encastered at one end and free at the other the effective length istaken as twice the length of the bar.



3 - Because of the uncertainty which exist at present about the effect of fixity on bars incompression between two connections, the effects of fixity are not taken into considerationand the bar is designed as if it were hinged at both ends, the effective length therefore beingtaken as the length between points of intersection of axes.

The case of bars subjected to compression and bending :

In the case of bars loaded eccentrically or loaded axially with a moment causing bending in thebar :

- either check the following two formulae :

F / S + ( Mf . v ) / I ≤ σa

and

ω . F / S + 0,9 . Mf . v / I ≤ σa

where :

F is the compressive load applied to the bar,

S is the section area of the bar,

Mf is the bending moment at the section considered,

v is the distance of the extreme fibre from the neutral axis,

I is the moment of inertia ;

- or perform the precise calculation in terms of the deformations sustained by the bar under thecombined effect of bending and compression, the necessary calculation being effected eitherby integration or by successive approximations.



Table T.A.3.3.1. - Value of the coefficient ωωωω in terms of the slenderness ratiofor rolled sections in St 37 steel (Fe 360)

λ 0 1 2 3 4 5 6 7 8 920

30

40

1,04

1,08

1,14

1,04

1,09

1,14

1,04

1,09

1,15

1,05

1,10

1,16

1,05

1,10

1,16

1,06

1,11

1,17

1,06

1,11

1,18

1,07

1,12

1.19

1,07

1,13

1,19

1,08

1,13

1,20

50

60

70

80

90

1,21

1,30

1,41

1,55

1,71

1,22

1,31

1,42

1,56

1,73

1,23

1,32

1,44

1,58

1,74

1,23

1,33

1,45

1,59

1,76

1,24

1,34

1,46

1,61

1,78

1,25

1,35

1,48

1,62

1,80

1,26

1,36

1,49

1,64

1,82

1,27

1,37

1,50

1,66

1,84

1,28

1,39

1,52

1,68

1,86

1,29

1,40

1,53

1,69

1,88

100

110

120

130

140

1,90

2,11

2,43

2,85

3,31

1,92

2,14

2,47

2,90

3,36

1,94

2,16

2,51

2,94

3,41

1,96

2,18

2,55

2,99

3,45

1,98

2,21

2,60

3,03

3,50

2,00

2,23

2,64

3,08

3,55

2,02

2,27

2,68

3,12

3,60

2,05

2,31

2,72

3,17

3,65

2,07

2,35

2,77

3,22

3,70

2,09

2,39

2,81

3,26

3,75

150

160

170

180

190

3,80

4,32

4,88

5,47

6,10

3,85

4,38

4,94

5,53

6,16

3,90

4,43

5,00

5,59

6,23

3.95

4,49

5,05

5,66

6,29

4,00

4,54

5,11

5,72

6,36

4,06

4,60

5,17

5,78

6,42

4,11

4,65

5,23

5,84

6,49

4,16

4,71

5,29

5,91

6,55

4,22

4,77

5,35

5,97

6,62

4,27

4,82

5,41

6,03

6,69

200

210

220

230

240

6,75

7,45

8,17

8,93

9,73

6,82

7,52

8,25

9,01

9,81

6,89

7,59

8,32

9,09

9,89

6,96

7,66

8,40

9,17

9,97

7,03

7,73

8,47

9,25

10,05

7,10

7,81

8,55

9,33

10,14

7,17

7,88

8,63

9,41

10.22

7,24

7,95

8,70

9,49

10,30

7,31

8,03

8,78

9,57

10,39

7,38

8,10

8,86

9,65

10,47

250 10,55



Table T.A.3.3.2. - Value of the coefficient ωωωω in terms of the slenderness ratio λλλλfor rolled sections in St 52 steel (Fe 510)

λ 0 1 2 3 4 5 6 7 8 920

30

40

1,06

1,11

1,19

1,06`

1,12

1,19

1,07

1,12

1,20

1,07

1,13

1,21

1,08

1,14

1,22

1,08

1,15

1.23

1,09

1,15

1,24

1,09

1,16

1,25

1,10

1,17

1,26

1,11

1,18

1,27

50

60

70

80

90

1,28

1,41

1,58

1.79

2,05

1,30

1,43

1,60

1,81

2,10

1,31

1,44

1,62

1,83

2,14

1,32

1,46

1,64

1,86

2.19

1,33

1,48

1,66

1,88

2,24

1,35

1,49

1,68

1,91

2,29

1,36

1,51

1,70

1.93

2,33

1,37

1,53

1,72

1,95

2,38

1,39

1,54

1.74

1,98

2,43

1,40

1,56

1,77

2,01

2,48

100

110

120

130

140

2,53

3,06

3,65

4,28

4,96

2,58

3,12

3,71

4,35

5,04

2,64

3,18

3,77

4,41

5,11

2,69

3,23

3,83

4,48

5,18

2,74

3,29

3,89

4,55

5,25

2,79

3,35

3,96

4,62

5,33

2,85

3,41

4,02

4,69

5,40

2,90

3,47

4,09

4,75

5,47

2,95

3.53

4,15

4,82

5.55

3,01

3.59

4,22

4,89

5,62

150

160

170

180

190

5,70

6,48

7,32

8,21

9,14

5,78

6,57

7,41

8,30

9,24

5,85

6,65

7,49

8,39

9,34

5,93

6,73

7,58

8,48

9,44

6,01

6,81

7,67

8,58

9,53

6,09

6,90

7,76

8,67

9,63

6,16

6,98

7,85

8,76

9,73

6,24

7,06

7,94

8,86

9,83

6,32

7,15

8,03

8,95

9.93

6,40

7,21

8,12

9,05

10,03200

210

220

230

240

10,13

11,17

12,26

13,40

14,59

10,23

11,28

12,37

13,52

14,71

10,34

11,38

12,48

13,63

14,83

10,44

11,49

12,60

13,75

14,96

10,54

11,60

12,71

13,87

15,08

10,65

11,71

12,82

13,99

15,20

10,75

11,82

12,94

14,11

15,33

10,85

11,93

13,05

14,23

15,45

10,96

12,04

13,17

14,35

15,58

11,06

12,15

13,28

14,47

15,71

250 15,83



Table T.A.3.3.3. - Value of the coefficient ωωωω in terms of the slenderness ratio λλλλfor tubes in St 37 steel (Fe 360)

λ 0 1 2 3 4 5 6 7 8 920

30

40

1,00

1,03

1,07

1,00

1,03

1,07

1,00

1,04

1,08

1,00

1,04

1,08

1,01

1,04

1,09

1,01

1,05

1,09

1,01

1,05

1,10

1,02

1,05

1,10

1,02

1,06

1,11

1,02

1,06

1,11

50

60

70

80

90

1,12

1,19

1,28

1,39

1,53

1,13

1,20

1,29

1,40

1,54

1,11

1,20

1,30

1,41

1,56

1,14

1,21

1,31

1,42

1,58

1,15

1,22

1,32

1,44

1,59

1,15

1,23

1,33

1,46

1,61

1,16

1,24

1,34

1,47

1,63

1,17

1,25

1,35

1,48

1,64

1,17

1,26

1,36

1,50

1,66

1,18

1,27

1,37

1,51

1,68

100

110

1,70

2,05

1,73

2,08

1,76

2,12

1,79

2,16

1,83

2,20

1,87

2,23

1,90 1,94 1,97 2,01

For λ > 115 take the value of ω in T.A.3.3.1.

Table T.A.3.3.4. - Value of the coefficient ωωωω in terms of the slenderness λλλλ ratiofor tubes in St 52 steel (Fe 510)

λ 0 1 2 3 4 5 6 7 8 920

30

40

1,02

1,05

1,11

1,02

1,06

1,11

1,02

1,06

1,12

1,03

1,07

1,13

1,03

1,07

1,13

1,03

1,08

1,14

1,04

1,08

1,15

1,04

1,09

1,16

1,05

1,10

1,16

1,05

1,10

1,17

50

60

70

80

90

1,18

1,28

1,42

1,62

2,05

1,19

1,30

1,44

1,66

1,20

1,31

1,46

1,71

1,21

1,32

1,47

1,75

1,22

1,33

1,49

1,79

1,23

1,35

1,51

1,83

1,24

1,36

1,53

1,88

1,25

1,38

1,55

1,92

1,26

1,39

1,57

1,97

1,27

1,41

1,59

2,01

For λ > 90 take the value of ω in T.A.3.3.2.Note : The values of ω in table T.A.3.3.3. and T.A.3.3.4. are valid for calculating the case of anaxially loaded bar consisting of a single tube whose diameter is equal to at least six times itsthickness.



A - 3.4. - CHECKING STRUCTURAL MEMBERS SUBJECT TO BUCKLING

From the theoretical standpoint, the critical buckling stress σvcr is regarded as a multiple of the

EULER Stress given by the formula :σE

R = π2 . E . ( e / b )2 / [ 12 . ( 1 - η2 ) ]

representing the critical buckling stress for a strip of thickness e, having a width equal to b, thisbeing the plate dimension measured in the direction perpendicular to the compression forces(see sketch below).

In this formula, E is the modulus of elasticity and η Poisson's Ratio.

For normal steels in which E = 210 000N/mm2 and η = 0,3, the EULER Stress becomes :σE

R = 189 800 . ( e / b )2

The critical buckling stress σvcr must be a multiple of this value, whence :

σvcr = κσ . σ

ER

in the case of compression.

In the case of shear the critical stress is :τv

cr = κτ . σE

R

The coefficients κσ and κτ, known as the buckling coefficients, depend on :

- the ratio α = a / b of the two sides of the plate

- the manner in which the plate is supported along the edges

- the type of loading sustained by the plate in its own plane

- any reinforcement of the plate by stiffeners.

Value of coefficients κσ and κτ

Without wishing to enter into the details of this problem, which is the subject of specialisedworks and of particular standards, we give hereafter values of κσ and κτ for a few simple cases(see table T.A.3.4.1.).

For more complex cases, reference should be made to specialised literature.



Combined compression and shear

Taking σ and τ to be calculated stresses in compression and in shear the critical comparisonstress σv

cr.c is determined from the expression :

σvcr.c = (σ2 + 3 τ2 )0,5 / [ ( 1 + ψ) / 4 ] . ( σ / σv

cr ) + [ 0,25 . ( 3 - ψ ) . σ / σvcr ]

2 . [ τ / τvcr ]

2 0,5

ψ being defined in the table T.A.3.4.1.

Important note : It is essential to note that the formulae above giving the critical stresses σvcr

and σvcr.c apply only when the values determined thus are below the limit of proportionality (i.e.

190 N/mm2 for A.37 steel, 290 N/mm2 for A.52 steel).

Similarly, the formula giving τvcr applies only when the value 30,5 . τv

cr is below the limit ofproportionality.

Whenever the formulae give values above these limits, it is necessary to adopt a limiting criticalvalue, obtained by multiplying the calculated critical value by the coefficient ρ given in the tableT.A.3.4.2., which also indicates the reduced values corresponding to various calculated valuesof σv

cr and τvcr .



Table T.A.3.4.1.Value of the buckling coefficients κκκκσσσσ and κκκκττττ for plates supported at their four edges

No. CASE α = a / b κσ or κτ1 Simple uniform compression α ≥ 1

α ≤ 1

κσ = 4

κσ = (α + 1 / α)2

2 Non-uniform compression α ≥ 1

α ≤ 1

κσ = 8,4 / ( ψ + 1,1 )

κσ = 2,1 . (α + 1 / α)2 / ( ψ + 1,1 )

3 Pure bending ψ = - 1 or bendingwith tension preponderant

α ≥ 2 / 3

α ≤ 2 / 3

κσ = 23,9

κσ = 15,87 + 1,87 / α2 + 8,6 α2

4 Bending with compressionpreponderant - 1 < ψ< 0

κσ = ( 1 + ψ ) . κ‘ - ψ . κ‘’ + 10 . ψ . ( 1 + ψ )where :κ‘ = value of κσ for ψ = 0 in case n° 2κ‘’ = value of κσ for pure bending (case n°. 3)

5 Pure shear α ≥ 1

α ≤ 1

κτ = 5,34 + 4 / α2

κτ = 4 + 5,34 / α2

Table T.A.3.4.2. - Values of ρρρρ and the reduced critical stresses σσσσvcr , σσσσ

vcr.c and ττττv

cr

(N/mm2)σv

cror

σvcr.c

calculated

τvcr

calculatedρ

σvcr

or

σvcr.c

reduced

τvcr

reduced

σvcr

or

σvcr.c

calculated

τvcr

calculatedρ

σvcr

or

σvcr.c

reduced

τvcr

reduced

Steel St 37 (Fe 360) Steel St 52 (Fe 510)190200210220230240250260280300340

110116121127133139145150162173197

1,000,970,940,910,880,850,820,800,760,720,65

190194197200202204206208212215221

110113114116117118119120122124128

290300310320330340350360380400440

168173179185191196202208220231254

1,000,980,960,940,920,900,880,860,820,790,73

290294297300303306308309312316322

168169172174175176177178180182185



Determination of permissible buckling stresses

After the critical buckling stresses have been determined as indicated above, the permissiblestress is obtained by dividing the critical stress by the coefficient νV determined in clause 3.4.

The calculations are then performed as follows :

The stresses are determined for each case of loading, in accordance with clause 3.4., afterwhich a check is made to ensure that these calculated stresses do not exceed the permissiblestresses determined as indicated above.

Note : In the case of combined compression and shear, the critical comparison stress σvcr.c must

be compared with the comparison stress calculated from the formula in clause 3.2.1.3. :σcp = ( σ2 + 3 . τ2 )0,5

Example of checking for buckling

Take the case of a plate girder in St 37 steel, having a span of 10 m, a depth of 1,50 m, a webthickness of 0,010 m, a uniformly distributed load of 162 kN/m and stiffeners 1,25 m apart.

Reactions on supports : A = B = 810 kNMoment of inertia of the beam = 1 419 000 cm4

Checking at section MN, located 0,625 m from ABending moment at MN :

Mf = 810 x 0 625 - ( 162 x 0,6252 ) / 2 = 474,7 kNm

Upper stress (compression) :

σ1 = - ( 474,7 x 106 x 0,84 x 103 ) / ( 1 419 000 . 104 ) = - 28 N/mm2

Lower stress (tension) :

σ2 = ( 474,7 x 106 x 0,66 x 103 ) / ( 1 419 000 . 104 ) = 22 N/mm2

These stresses are calculated at the upper and longer edges of the web.



shear stress :( 810 . 103 - 162 . 0,625 . 103 ) / ( 10 . 1500 ) = 47 N/mm2

Bending (case 4 - compression preponderant) :

ψ = 0,22 / -0,28 = -0,79 α = 1,25 / 1,50 = 0,83 (< 1 )

giving κσ = ( 1 + ψ ) . κ‘ - ψ . κ‘’ + 10 . ψ . ( 1 + ψ )

in which κ‘ = ( α+ 1 / α )2 . 2,1 / ( 0 + 1,1 ) = ( 0,83+ 1 / 0,83 )2 . 2,1 / 1,1 = 7,90

and κ‘’ = 23,9

whence κσ = ( 1- 0,79 ) . 7,90 + 0.79 . 23,9 - 10 . 0,79 . ( 1 - 0,79 ) = 18,88

The Euler Stress :σE R = 189 800 . ( e / b )2 = 189 800 ( 10 / 1500 )2 = 8,4 N/mm2

giving a critical buckling stress :σv

cr = κσ . σE

R = 18,88 . 8,4 = 158,6 N/mm2

Shear : κτ = 4 + 5,34 / σ2 = 4 + 5,34 / 0,832 = 11,75

and τvcr = κτ . σ

E R = 11,75 . 8,4 = 99 N/mm2

The critical comparison stress then becomes : σvcr.c =

( 282 + 3 . 472 )0,5

________________________________________________________________________________________________________________

[ ( 1 - 0,79 ) / 4 ] . ( 28 / 158,5 ) + [ 0,25 . ( 3 + 0,79 ) . 28 / 158,5 ]2 . [ 47 / 99 ]2 0,5

σvcr.c = 168 N/mm2



Conclusion :

The comparison stress in the case of tension (or compression) combined with shear is given inclause 3.2.1.3.

( σ2 + 3 τ2 )0,5 = 86 N/mm2.

This value is smaller than the critical buckling stress given in 3.4. (with νV = 1,4)168 / 1,4 = 120 N/mm2 for loading case I.

The permissible buckling stress is therefore not exceeded in loading case I.

Naturally, a check must also be made to ensure that the permissible buckling stresses are notexceeded in loading cases II and III.

Checking of buckling for circular cylinders :

Thin wall circular cylinders such as, for exempla, large tubes, which are subject to central oreccentric axial compression have to be checked for local buckling if :

t / r ≤ 25 . σE / E

where :t = thickness of the wall ;r = radius from the middle of the wall thickness ;σE = elastic limit of the steel type, as in table T. 3.2.1.1.E = modulus of elasticity, see A-3.4.

The ideal buckling stress σvi can be determined from :

σvi = 0,2 E . t / r

In all cases where σvi is situated above the limit of proportionality of the structural steel, the ideal

buckling stress σvi has to be reduced to σv

by means of the factor ρ.

At a maximum spacing of 10 . r, transverse stiffeners have to be provided whose moment ofinertia has to be at least :

I = 0,5 . r . t3 / ( r / t )0,5

The moment of inertia is calculated from the following formulae :

1 - Central disposition of the stiffener F (centre of gravity of the stiffener section in the medianplane of the wall thickness).



2 - Eccentric disposition of the stiffener F (centre of gravity of the stiffener section F2 outside themedian plane of the wall 1). .

I = I1 + I2 + F1 . e12 + F2 . e2

2

It is accepted that this calculation of σvi and σv respectively takes account of geometrical

divergences between the real and the ideal cylinder surfaces due to local construction defectsup to a dimension of t / 2.



A - 3.6. - CHECKING STRUCTURAL MEMBERS SUBJECT TO FATIGUE

It must be remembered that fatigue is one of the causes of failure envisaged in clause 3.6. andtherefore checking for fatigue is additional to checking in relation to the elastic limit ofpermissible crippling or buckling.

If the permissible stresses for fatigue, as determined thereunder, are higher than those allowedfor other conditions then this merely indicates that the dimensions of the components are notdetermined by considerations of fatigue.

Clause 3.6. enumerates the parameters which must be considered when checking structuralcomponents for fatigue.

The purpose of this appendix is firstly to classify the various joints according to their notcheffect, as defined in clause 3.6.2. and, then, to determine for these various notch effects and foreach classification group of the component as defined in clause 2.1.4. the permissible stressesfor fatigue as a function of the coefficient κ defined in clause 3.6.4.

These permissible fatigue stresses were determined as a result of tests carried out by theF.E.M. on test pieces having different notch effects and submitted to various loading spectre.They were determined on the basis of the stress values which, in the tests, assured 90 %survival including a factor of safety of 4/3.

In practice, a structure consists of members which are welded, riveted or bolted together andexperience shows that the behaviour of a member differs greatly from one point to another ; theimmediate proximity of a joint invariably constitutes a weakness that will be vulnerable to avarying extent according to the method of assembly used.

An examination is therefore made in the first sections, of the effect of fatigue on structuralmembers both away from any joint and in immediate proximity to the usual types of joint.

The second section examines the resistance to fatigue of the means of assembly themselves,i.e. weld seams, rivets and bolts.



1 - VERIFICATION OF STRUCTURAL MEMBERS

The starting point is the fatigue strength of the continuous metal away from any joint and, ingeneral, away from any point at which a stress concentration, and hence a lessening of thefatigue strength, may occur.

In order to make allowance for the reduction in strength near joints, as a result of the presenceof holes or welds producing changes of section, the notch effects in the vicinity of these joints,which characterize the effects of the stress concentrations caused by the presence ofdiscontinuities in the metal, are examined.

These notch effects bring about a reduction of the permissible stresses, the extent of whichdepends upon the type of discontinuity encountered, i.e. upon the method of assembly used.

In order to classify the importance of these notch effects, the various forms of joint constructionare divided into categories as follows :

Unwelded parts

These members present three cases of construction.

Case WO concerns the material itself without notch effect.

Cases W1 and W2 concern perforated members (see table T.A.3.6.(1))

Welded parts

These joints are arranged in order of the severity of the notch effect increasing from K0 to K4,corresponding to structural parts located close to the weld fillets.

The table T.A.3.6. (1) gives some indications as to the quality of the welding and a classificationof the welding and of the various joints that are most often used in the construction of liftingappliances.

Determination of the permissible stresses for fatigue

Tensile and compressive loads

The basis values which have been used to determine the permissible stresses in tension andcompression are those resulting from the application of a constant alternating stress± σW (κ = - 1 ) giving a survival rate of 90 % in the tests, to which a factor of safety of 4/3 hasbeen applied.

To take account of the number of cycles and of the stress spectrum, the σW values have beenset for each classification group of the member the latter taking account of these twoparameters.

For unwelded parts, the values σW are identical for steel St 37, and St 44.They are higher for St 52.

For welded parts, the σW values are identical for the three types of steel.



Table T.A.3.6.1.Values of σσσσW depending on the component group and construction case (N/mm2)

Com-Unwelded components

Construction cases

Welded componentsConstruction cases

(Steels St 37 to St 52, Fe 360 to Fe 510)ponent W0 W1 W2

group Fe 360St 37St 44

St 52Fe 510

Fe 360St 37St 44

St 52Fe 510

Fe 360St 37St 44

St 52Fe 510

K0 K1 K2 K3 K4

E1

E2

E3

E4

E5

E6

E7

E8

249,1

224,4

202,2

182,1

164,1

147,8

133,2

120,0

298,0

261,7

229,8

201,8

177,2

155,6

136,6

120,0

211,7

190,7

171,8

154,8

139,5

125,7

113,2

102,0

253,3

222,4

195,3

171,5

150,6

132,3

116,2

102,0

174,4

157,1

141,5

127,5

114,9

103,5

93,2

84,0

208,6

183,2

160,8

141,2

124,0

108,9

95,7

84,0

(361,9)

(293,8)

238,4

193,5

157,1

127,5

103,5

84,0

(323,1)

262,3

212,9

172,8

140,3

113,8

92,4

75,0

(271,4)

220,3

178,8

145,1

117,8

95,6

77,6

63,0

193,9

157,4

127,7

103,7

84,2

68,3

55,4

45,0

116,3

94,4

76,6

62,2

50,5

41,0

33,3

27,0

The values in brackets are greater than 0,75 times the breaking stress and are only theoreticalvalues (see note 2 at the end of this clause).

The following formulae give for all values of κ the permissible stresses for fatigue

a) κ ≤ 0- for tension : σt = 5 . σw / ( 3 - 2 . κ ) (1)

- for compression : σc = 2 . σw / ( 1 - κ ) (2)

σw is given in table above.

b) κ > o- for tension σt = σO / [ 1 - κ . (1 - σO / σ+1 ) ] (3)

- for compression σc = 1,2 . σt (4)



where σO = tensile stress for κ = 0 is given by the formula (1) that is :σO = 1,66 . σw

σ+1 = tensile stress for κ = + 1 that is the ultimate strength σR divided by the coefficient of safety4/3 : σ+1 = 0,75 . σR

σt is limited in every case to 0,75 . σR .

By way of illustration, fig. A.3.6.1. shows curves giving the permissible stress as a function ofthe ratio κ for the following cases :

- steel A.52 ;- predominant tensile stress ;- group E6 ;- construction cases W0, W1, W2 for unwelded components and cases of construction for

joints K0 to K4.

The permissible stresses have been limited to 240 N/mm2, i.e. to the permissible stress adoptedfor checking for ultimate strength.

[permissible stress)

Ratio between the extreme stressesFigure A.3.6.1. - (A 52; tension; group E6)



Shear stresses in the material of structural parts

For each of the group from E1 to E8 the permissible fatigue stress in tension of the case wO

divided by 30,5 is taken :τa = σt of case wO / 30,5

Combined loads in tension (or compression) and shear

In this case the permissible stresses for fatigue for each normal load in tension (orcompression) σxa and σya and shear τxya are determined by assuming that each acts separatelytaking respectively the following values of κ in accordance with clause 3.6.4. :

κx = σx min / σx max κy = σy min / σy max κxy = τxy min / τxy max

Then the following three conditions are checked :

σx max < σxa σy max < σya τxy max < τxya

None of the calculated sheares should exceed the permissible value of σa in case I loading (seetable T.3.2.1.1.).

a) If any one stress is markedly greater than the other two in any given case of loading, it willsuffice to check the member for fatigue under the corresponding load, neglecting the effect ofthe other two.

b) In the other cases, in addition to checking for each loading assumed to act alone, it isrecommended that the following relationship be checked :

(σx max / σxa )2 + (σy max / σya )

2 - σx max . σy max / ( | σxa | . | σya | ) + ( τxy max / τxya )2

≤ 1 2 (5)

where the stress values σxa, σya and τxya are those resulting from the application of formulae (1),(2), (3) and (4) limited to 0,75 . σR.

2 As this inequality constitutes a severe requirement, values slightly higher than 1 are acceptable, but inthis case it is necessary to check the relation :[ (σx max / σxa )

2 + (σy max / σya )2 - σx max . σy max / ( | σxa | . | σya | ) + ( τxy max / τxya )

2 ]

0,5 ≤ 1,05It should also be noted that the values | σxa | and | σya | in the denominator for the third term should betaken as absolute values, σx max and σy max being assigned their algebraic values.



In applying this formula, reference should be made to the directions given in clause 3.2.1.3. Inother words :

- either perform the check by combining the maximum values σx max , σy max and τxy max andcomparing with the permissible stresses σxa, σya and τxya computed on the basis of the mostunfavourable values of κ.

- or seek the most unfavourable combination actually possible by making the check with thefollowing values :

a) σx max and κx min with the corresponding values of σy, τxy, κy and κxy

b) σy max and κy min with the corresponding values of σx, τxy, κx and κxy

c) τxy max and κxy min with the corresponding values of σx, σy, κx and κy

In this connection, see note in clause 3.2.1.3.

In order to facilitate the calculations, table T.A.3.6.2. gives the permissible values of :

τxy max / τxya as a function of σx max / σxa and of σy max / σya

In this table, the values of σx max / σxa are given in the left hand column with the followingconvention : the ratio is considered to be positive if σx max and σy max have the same sign,and negative otherwise.



Table T.A.3.6.2. - Values of ττττxy max / ττττxya in terms of σσσσx max / σσσσxa and σσσσy max / σσσσya

σx max σy max / σya________

σxa 1,0 0,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0,1 0+ 1,0

+ 0,9

+ 0,8

+ 0,7

+ 0,6

+ O,5

+ 0,4

+ 0,3

+ 0,2

+ 0,1

0

- 0,1

- 0,2

- 0,3-

- 0,4

- 0,5

- 0,6

- 0,7

- 0,8

- 0,9

- 1,0

0

0,300

0,400

0,458

0,490

0,500

0,490

0,458

0,400

0,300

0

0,300

0,436

0,520

0,575

0,608

0,625

0,625

C,608

0,575

0,520

0,436

0,300

0,400

0,520

0,600

0,656

0,693

0,714

0,721

0,714

0,693

0,656

0,600

0,520

0,400

0,173

0,458

0,575

0,656

0,714

0,755

0,781

0,794

0,794

0,781

0,755

0,714

0,656

0,575

0,458

0,265

0,490

0,608

0,693

0,755

0,800

0,831

0,849

0,854

0,849

0,831

0,800

0,755

0,693

0,608

0,490

0,300

0,500

0,625

0,714

0,781

0,831

0,866

0,889

0,900

0,900

0,889

0,866

0,831

0,781

0,714

0,625

0,500

0,300

0,490

0,625

0,721

0,794

0,849

0,889

0,917

0,933

0,938

0,933

0,916

0,889

0,849

0,794

0,721

0,625

0,490

0,265

0,458

0,608

0,714

0,781

0,854

0,900

0,933

0,954

0,964

0,964

0,9S4

0,933

0,900

0,854

0,781

0,714

0,608

0,458

0,173

0,400

0,575

0,693

0,781

0,849

0,900

0,938

0,964

0,980

0,985

0,980

0,964

0,938

0,900

0,849

0,781

0,693

0,575

0,400

0,300

0,520

0,656

0,755

0,831

0,889

0,933

0,964

0,985

0,995

0,99S

0,98S

0,964

0,933

0,889

0,831

0,755

0,656

0,520

0,300

0

0,436

0,600

0,714

0,800

0,866

0,917

0,954

0,980

0,995

1,000

0,995

0,980

0,954

0,917

0,866

0,800

0,714

0,600

0,436

0

If σx max and σy max are of opposite sign (tension or compression) read the values ofτxy max / τxya starting from the negative values of σx max / σxa



General notes

Note 1 - In applying the above considerations, it is essential to take into account the secondarybending effects which a particular method of assembly may cause in the members of thestructure.

Note 2 - If reference is made to the table of values of σw it can be seen that in group E1 and E2much higher stresses than those usually permitted in structures are quoted. These values are infact only theoretical values obtained by extrapolation of the test results on higher group (E3 toE8) with medium or severe notch cases (K2, K3 and K4). Therefore there is no need to attachany material significance to these values in brackets, consideration of which could in somecases lead to the conclusion that an assembly of type K0 or K1 could resist fatigue better thanthe unwelded metal (case WO). This apparent anomaly illustrates the well known fact that it isnot always necessary to carry out fatigue checks for the longer group with slight or moderatenotch cases.

With respect to the calculations it must be remembered that these theoretical σw values areused only to determine the permissible fatigue stresses σxa , σya and τxya for use in formula (5)which covers the case of combined loads.

Examples of calculations are given at the end of the Appendix.



2 - VERIFICATION OF THE JOINING MEANS (welds, bolts, rivets)

Welds

a) Tensile and compressive loads in the welds :

Welds subjected to fatigue under tensile and compressive loads are checked using the samepermissible stresses as those of the metal joined.

Note - The limit indicated under 3.2.2.3. for certain particular cases of transverse tension andcompression in weld seams must be observed.

Appendix A-3.2.2.3. gives, in addition, some indications for the determination of the stressesin the weld seams.

b) Shear loads in the welds :

The permissible shear fatigue stresses in the welds are determined by dividing thepermissible stresses in tension for case K0 by 20,5

c) Combined loads :

The method set out above for structural members is used when considering the effect offatigue in weld seams subjected to variable combined loads.

Bolts and rivets

a) Tensile loads :

Fatigue due to variable tensile loads in bolts and rivets need not be considered.

In this connection, it should be noted that bolts and, even more important, rivets working intension should be avoided as far as possible.

b) Shear loads and bearing pressure :

Single and multiple shear loads as defined under 3.2.2.1.1. must be distinguished.

The permissible shear stresses for fatigue for bolts and rivets are fixed by multiplying thepermissible stresses in tension for case W2 by :

0,6 for single shear 0,8 for multiple shear

The permissible bearing pressure values are obtained by multiplying the permissible shearvalues in the bolts and rivets by 2,5.



Table T.A.3.6.(1) - Classification of cases of construction for joints

Joints may be riveted, bolted or welded.

The types of weld most commonly used for hoisting appliances are butt welds, double bevel buttwelds (K welds) and fillet welds, of ordinary quality (O.Q.) or special quality (S.Q.) as specifiedbelow.

Weld testing is also stipulated for certain types of joint.



A - Weld qualities

Type of weldWeld

quality Execution of weld 3

Symbol Weld testing Symbol

Full depthbutt weld

Specialquality(S.Q.)

Root of weld scraped(or trimmed) beforemaking sealing run.No end craters.Weld ground flushwith plate parallel todirection of forces

Check (e.g. with X-rays)over 100 % of seamlength

P 100

Ordinaryquality

Root of weld scraped(or trimmed) before

If the calculatedstress > 80 % timesthe permissible stress

P 100

(O.Q.) making sealing run.No end craters

Otherwise randomcheck over at least10 % of seam length

P 10

K-weld inangle formedby two partswith bevel on


Root of weld scraped(or trimmed) beforemaking weld on otherside. Weld edgeswithout undercuttingand ground ifnecessary.Full penetration welds

Check that for tensileloads the plate D

one of theparts to bejoined atlocation ofseam

Ordinaryquality(O.Q.)

Width clear of weldpenetration between

the two welds < 3 mm

perpendicular to thedirection of the forcesis free from lamination.

Fillet weldsin the angleformed by


Welded edgeswithout undercuttingand ground ifnecessary

Check that for tensileloads the plateperpendicular to thedirection of the forcesis free from lamination

D

two parts Ordinaryquality(O.Q.)

Table T.A.3.6.(1) (continued)B - Cases of construction for joints

In the tables below the various cases of means of assembly are classified in terms of themagnitude of the notch effect they produce.

3 It is forecasted that the symbol shall be adapted to the ISO standard 2553 at the next editionof the Design Rules, when the addition of this standard will be definitively adopted.



It should be noted that, with a given weld, the notch effect differs according to the type ofloading to which the joint is-subjected.

For exempla, a fillet welded joint is classified under case K0 for longitudinal tension orcompression loads (0,31) or longitudinal shear (0,51), and under cases K3 or K4 for transversetension or compression loads (3,2 or 4,4).

1 - Non welded parts

Case WO

Reference Description Figure Symbol

WO

Parent metal, homogeneous surface.Part without joints or breaks in continuity(solid bars) and without notch effectsunless the latter can be calculated.

Case W1


W1

Parts drilled. Parts drilled for riveting orbolting with rivets and bolts loaded upto 20 % of permissible values. Partsdrilled for joints using high strengthbolts (C1 3.2.2.2.2.3.) loaded up to 100% of permissible values(C1 3.2.2.2.2.2.)

Case W2


W2.1

Parts drilled for riveting or bolting inwhich the rivets or bolts are loaded inmultiple shear

W2.2

Parts drilled for riveting or bolting, inwhich the rivets or bolts are loadedin single shear (allowing for eccentricloads), the parts being unsupported

W2.3

Parts drilled for assembling by meansof rivets or bolts loaded in single shear,the parts being supported or guided



2 - welded parts

Case K0 - Slight stress concentration


0,1 Parts butt-welded (S.Q.) at rightangles to direction of forces P 100

0,11

Parts of different thickness butt-welded (S.Q.) at right angles todirection of forces.Asymmetrical slope : 1/4 to 1/5;Symmetrical slope : 1/3

P 100

0,12Butt weld (S.Q.) in transverse joint ofweb plate P 100

0,13Gusset secured by butt-welding (S.Q.)at right angles to the direction of theforces

P 100

0,3Parts joined by butt-welding (O.Q.)parallel to the direction of the forces P 100

or P10

0,31Parts joined by fillet welds (O.Q.)parallel to the direction of the forces(longitudinal to the joined parts)

0,32Butt weld (O.Q.) between sectionforming flange and web of a beam P 100

or P 10

0,33

K- or fillet weld (O.Q.) between flangeand web of a beam calculated for theequivalent stress for combined forces(C1 3.2.1.3.)



Case K0 - Slight stress concentration (continued)


0,5Butt weld (O.Q.) in the case oflongitudinal shear P 100

or P10

0,51 K-weld (O.Q.) or fillet weld (O.Q.) inthe case of longitudinal shear

Case K1 - Moderate stress concentration


1,1Parts joined by butt welding (O.Q.) atright angles to the direction of theforces

P 100or P10

1,11

Parts of different thickness buttwelded (O.Q.) at right angles to thedirection of the forces. Asymmetricalslope : 1 in 4 to 1 in 5 (or symmetricalslopes : 1 in 3)

P 100or P10

1,12 Butt weld (O.Q.) executed fortransverse joint of web plate P 100

or P10

1,13Gusset joined by butt welding (O.Q.)at right angles to the direction of theforces

P 100or P10

1,2

Continuous main member to which arejoined by continuous K-welds (S.Q.)parts at right angles to the direction offorces



Case K1 - Moderate stress concentration (continued)


1,21

Web plate to which stiffeners arejoined at right angles to the directionof the forces by means of fillet welds(S.Q.) which extend round the cornersof the web stiffeners

1,3Parts joined by butt welding parallel tothe direction of the forces (withoutchecking the welding)

1,31K-weld (S.Q.) between curved flangeand web

Case K2 - Medium stress concentration


2,1

Parts of different thickness buttwelded (O.Q.) at right angles to thedirection of the forces. Asymmetricalslope : 1 in 3 (or symmetrical slopes :1 in 2)

2,11Sections joined by butt welds (S.Q.) atright angles to the direction of theforces

P 100or P10

2,12Section joined to a gusset by a buttweld (S.Q.) at right angles to thedirection of the forces

P100

2,13

Butt weld (S.Q.) at right angles to thedirection of the forces, made atintersection of flats, with weldedauxiliary gussets. The ends of thewelds are ground, avoiding notches

P100



Case K2 - Medium stress concentration (continued)


2,2

Continuous main member to whichtransverse diaphragm, web stiffeners,rings or hubs are fillet welded (S.Q.) atright angles to the direction of theforces

2,21Web in which fillet welds (S.Q.) areused to secure transverse webstiffeners with cut corners, the weldsnot extending round the corners

2,22Transverse diaphragm secured byfillet welds (S.Q.) with cut corners, inwhich the welds do not extend roundthe corners

2,3

Continuous main member to theedges of which are butt welded (S.Q.)parts parallel to the direction of theforces. These parts terminal in bevelsor radii. The ends of the welds areground avoiding notches

P100

2,31

Continuous main member to which arewelded parts parallel to the direction ofthe forces. These parts terminal inbevels or radii. Valid where the endsof the welds are K-welds (S.Q.) over alength equal to ten times the thicknessprovided that the ends of the weldsare ground avoiding notches

2,33Continuous member to which a flat (1in 3 bevel) is joined by a fillet weld(S.Q.), the fillet weld being executed inthe X area, with a = 0,5 e

2,34 K-weld (O.Q.) made between curvedflange and web



Case K2 - Medium stress concentration (continued)


2,4Cruciform joint made with K-welds(S.Q.) perpendicular to the direction ofthe forces

D

2,41K-weld (S.Q.) between flange and webin the case of load concentrated in theplane of the web at right angles to theweld

2,5 K-weld (S.Q.) joining parts stressed inbending or shear

Case K3 - Severe stress concentration


3,1

Parts of different thickness connectedby butt welds (O.Q.) at right angles tothe direction of the forces. 1 in 2asymmetrical slope, or symmetricalposition without blend slope

P 100or P10

3,11Butt weld with backing strip and nobacking run. Backing strip secured byintermittent tack welds

3,12Tubes joined by butt welds whose rootis supported by a backing piece andnot covered by a backing run

3,13

Butt weld (O.Q.) at right angles to thedirection of the forces at theintersection of flats with weldedauxiliary gussets. The ends of thewelds are ground, avoiding notches



Case K3 - Severe stress concentration (continued)


3,2

Continuous main member to whichparts are fillet welded (O.Q.) at rightangles to the direction of the forces.These parts take only a small portionof the loads transmitted by the mainmember

3,21Web and stiffener or transversediaphragm secured by uninterruptedfillet weld (O.Q.)

3,3

Continuous member to the edges ofwhich are butt welded (O.Q.) partsparallel to the direction of the forces.These parts terminal in bevels andends of the welds are ground avoidingnotches

3,31

Continuous member to which arewelded parts parallel to the direction ofthe forces. These parts terminal inbevels or radii. Valid where the endsof the welds are fillet welds (S.Q.) overa length equal to 10 times thethickness, provided that the ends ofthe welds are ground, avoidingnotches

3,32

Continuous member through whichextends a plate, terminating in bevelsor radii parallel to the direction of theforces, secured by K-weld (O.Q.) overa length equal to 10 times thethickness

3,33

Continuous member to which iswelded a flat parallel to the direction ofthe forces, by means of fillet weld(S.Q.) in the indicated area whene1 < 1,5 . e2



Case K3 - Severe stress concentration (continued)


3,34

Members at the extremity of whichconnecting gussets are secured by afillet weld (S.Q.) when e1 ≤ e2 In caseof unilateral gusset allow for eccentricload

3,35

Continuous member to whichstiffeners parallel to the direction ofthe forces are welded. The ends of thewelds are fillet welds (S.Q.) over alength equal to ten times the thicknessand are ground avoiding notches

3,36

Continuous member to whichstiffeners parallel to the direction ofthe forces are secured by fillet welds(O.Q.) which are intermittent or madebetween indentations

3,4Cruciform joint made with K-weld(O.Q.) at right angles to the directionof the forces

D

3,41K-weld (O.Q.) between flange andweb in case of concentrated load inthe plane of the web at right angles tothe weld

3,5K-weld (O.Q.) joining parts stressed inbending and shear

D

3,7Continuous member to which sectionsor tubes are fillet welded (S.Q.)



Case K4 - Very severe stress concentration


4,1Parts of different thickness buttwelded (O.Q.) at right angles to thedirection of the forces. Asymmetricalposition without blend slope

4,11Butt welds (O.Q.) at right angles to thedirection of the forces, at theintersection of flats (no auxiliarygussets)

4,12Single bevel weld at right angles to thedirection of the forces, betweenintersecting parts (cruciform joint)

D

4,3Continuous member to the sides ofwhich are welded parts ending at rightangles, parallel to the direction of theforces

4,31

Continuous member to which parts,ending at right angles, parallel to thedirection of the forces, and receiving alarge proportion of the loadstransmitted by the main member, aresecured by fillet weld (O.Q.)

4,32Continuous member through whichextends a plate ending at right anglesand secured by fillet welding (O.Q.)

4,33Continuous member on which a flat issecured by means of a fillet weld(O.Q.) parallel to the direction of theforces



Case K4 - Very severe stress concentration (continued)


4,34Joint plate secured by (O.Q.) filletwelds (e1 = e2). In case of unilateraljoint plate allow for eccentric loads

4,35Parts welded one on the othersecured by fillet welds (O.Q.) in a slotor in holes

4,36Continuous members between whichconnecting gussets are secured byfillet welds (O.Q.) or butt welds (O.Q.)

4,4Cruciform joint made with fillet weld(O.Q.) at right angles to the directionof the forces

D

4,41Fillet weld (O.Q.) between flange andweb in the case of concentrated loadin the plane of the web at right anglesto the weld

4,5 Fillet welds (O.Q.) joining partsstressed in bending and shear -

D

4,7Continuous member to which sectionsor tubes are connected by fillet welds(O.Q.)



EXAMPLES OF CALCULATING CHECKS

EXAMPLES OF FATIGUE CHECKSFOR A WELDED WEB TO FLANGE JOINT STEEL St 37

TOP FLANGE OF GIRDER OF AN OVERHEAD TRAVELLING CRANE ON WHICH A CRABRUNS(Combined check for fatigue and elastic limit)

The results of stress calculations in the top fringe of the girder are as follows :

Longitudinal compression :

σx max = - 140 N/mm2

σx min = - 28 N/mm2

from which κ = 0,2

Lateral compression when the crab wheel passes :

σy max = - 100 N/mm2

σy min = 0 from

which κ = 0

Shear : changing sign when passing from one side to the other of the section:

τxy max = ± 40 N/mm2

from which κ = -1

Equivalent stress :

[ ( -140 )2 + ( -100 )2 - 140 . 100 + 3 . 402 ]0,5 = 144 < 160 N/mm2 ( σa )

acceptable (See clause 3.2.1.3.).



CHECKING FOR FATIGUE AND ELASTIC LIMIT

FIRST EXAMPLE - COMPONENT IN GROUP E4 WITH FILLET WELD (O Q )

1 - CHECKING MATERIAL ADJACENT TO THE WELDING

a) Longitudinal compression : case K0 (reference 0,31)

Checking for elastic limit :

σa = 160 N/mm2 (table T.3.2.1.1.)σx max = - 140 N/mm2

from which

| σx max l < σa

Checking for fatigue :

σw = 193,5 N/mm2 (table T.A.3.6.1.)

σa = 5 / 3 . σw = 322,5 N/mm2

σ+1 = 0,75 . σR = 270 N/mm2

σt is limited to 270 N/mm2

σc = - 1,2 . σt = - 324 N/mm2

σxa = - 324 N/mm2

l σx max l < l σxa l

b) Lateral compression : case K4 (reference 4,41)


σa = 160 N/mm2 (table T. 3.2.1.1.)


| σy max | < σa




σw = 62,2 N/mm2 (table T.A.3.6.1.)

σa = 5 / 3 . σw = 103,7 N/mm2

σt = σ0 = 107,7 N/mm2 (formula (3))

σc = 1,2 . σt = 124,4 N/mm2

σya = - 124,4 N/mm2

l σy max l < l σya |

c) Shear in the material


τxya = 160 / 30,5 = 92,4 N/mm2 (table T. 3.2.1.1.)

τxy max = + 40 N/mm2 (formula (1))

τxy max < τa


τw = 182,1 / 3 0,5 = 105,1 N/mm2 (table T.A.3.6.1.)

τa = τw = 105,1 N/mm2

τxya = 105,1 N/mm2

τXY max = 40 N/mm2

| τXY max l < τa

d) Checking for combined loads :

Use formula (5) :

Condition to be checked :

( -140 / -324 )2 + ( -100 / -124,4 )2 - ( -140 ) . ( -100 ) / ( 324 . 124,4 ) + ( 40 / 92,4 )2 = 0,672 < 1

therefore satisfied.



2 - CHECKING IN THE WELD

If the thickness of the two welds is equal to the thickness of the web, the stresses σx max, σy max

and τxy max have the same values as in 1 - above.

The permissible tensile and compressive stresses are the same as for 1 above (in the material),with respect to both checking for elastic limit and checking for fatigue. It follows that we candispense with a check for the cases corresponding to a) and b) above.

The permissible shear stresses, as regards checking for elastic limit, are obtained by dividingthe permissible tensile stress by 20,5 , instead of 30,5 in the case of the material itself. They aretherefore more favourable than those used in cases c) and d) above.

To sum up, we may confine ourselves to checking for fatigue the cases corresponding to c) andd) above.

c) Shear in the weld :

τxya = 193,5 / 20,5 = 136,8 N/mm2 (table T.A.3.6.1.)τxy max = 40 N/mm2

from which

| τxy max l < | τxya l


Using formula (5)


(-140 / -324 )2 + ( -100 / -124,4 )2 - ( -140 ) . (-100 ) / ( 324 . 124,4 ) + ( 40 / 136,8 )2 = 0,571 <1


Note : If the component had been classified in group E6, the stress σy max = - 100 N/mm2 wouldbe too high, since the permissible fatigue stress for case K4 and κ = 0 is only :

σya = 1,2 . 5 / 3 . 41 = 82 N/mm2



SECOND EXAMPLE - COMPONENT IN GROUP E6 - K WELD (S.Q.)

The loads - and therefore the stresses - will be assumed to be the same as in the first example.

As the permissible stresses for the elastic limit checks are not affected by the change of group,nor by the type of weld, the calculations in the first example may, in this respect, be reproducedas they stand. We shall therefore confine ourselves to checking for fatigue.

1 - CHECKING MATERIAL ADJACENT OT THE WELD

a) Longitudinal compression, case K0 (reference 0,33)

σw = 127,5 N/mm2 (table T.A.3.6.1.)

σO = 5 / 3 . σw = 212,5 N/mm2

σ+1 = 0,75 . σR = 270 N/mm2

σt = 212,5 / [ 1 - ( 1 - 212,5 / 270 ) . 0,2] = 222,0 N/mm2 (formula (3))

σc = - 1,2 . σt = 266 N/mm2 (formula (4))

σxa = - 266 N/mm2

σx max = - 140 N/mm2

from wihch l σx max l < l σxa l

b) Lateral compression : case K2 (reference 2,41)

σw = 95,6 N/mm2 (table T.A.3.6.1.)

σa = 5 / 3 . σw = 159,3 N/mm2

σt = σO = 159,3 N/mm2 (formula (3))

σc = - 1,2 . σt = 191,2 N/mm2

σya = - 191,2 N/mm2


from wihch l σy max l < l σya l



c) Shear in the material :

τxya = 147,8 / 30,5 = 85,3 N/mm2 (table T.A.3.6.1.)


from which | τxy max l < | τxya l


Use formula (5)


(-140 / -266 )2 + ( -100 / -191,2 )2 - ( -140 ) . (-100 ) / ( 266 . 191,2 ) + ( 40 / 85,3 )2 = 0,495 < 1


2 - CHECKING IN THE WELD

Same reasoning as for first example.

Leaving cases c) and d) to be checked for fatigue.

c) Shear in the weld :

τxya = 127,5 / 20,5 = 90,2 N/mm2 (table T.A.3.6.1.)


from which | τxy max l < | τxya l


Use formula (5)


(-140 / -266 )2 + ( -100 / -191,2 )2 - ( -140 ) . (-100 ) / ( 266 . 191,2 ) + ( 40 / 90,2 )2 = 0,472 < 1





SECTION I


F.E.M.

1.001 3rd EDITION

REVISED

1998.10.01


HOISTING APPLIANCES

B O O K L E T 4

CHECKING FOR FATIGUE AND CHOICE OF MECHANISM COMPONENTS





Booklet 4

CHECKING FOR FATIGUE AND CHOICE OF

MECHANISM COMPONENTS

4.1. CALCULATION PROCEDURE.....................................................................................................3

4.1.1. CHECKING FOR ULTIMATE STRENGTH .............................................................................34.1.1.1. VALUE OF THE PERMISSIBLE STRESS..................................................................................... 34.1.1.2. VALUES OF THE COEFFICIENT νR ............................................................................................ 44.1.1.3. RELATIONS BETWEEN THE CALCULATED STRESSES AND THE PERMISSIBLE STRESSES.... 4

4.1.2. CHECKING FOR CRIPPLING...................................................................................................5

4.1.3. CHECKING FOR FATIGUE........................................................................................................54.1.3.1. GENERAL METHOD................................................................................................................... 54.1.3.2. ENDURANCE LIMIT UNDER ALTERNATING LOADING OF A POLISHED SPECIMEN................... 64.1.3.3. INFLUENCE OF THE SHAPE, SIZE, SURFACE CONDITION AND CORROSION........................... 74.1.3.5. WÖHLER CURVE....................................................................................................................... 94.1.3.6. FATIGUE STRENGTH OF A MECHANICAL COMPONENT ........................................................ 114.1.3.7. PERMISSIBLE STRESSES AND CALCULATIONS .................................................................... 11

4.1.4. CHECKING FOR WEAR...........................................................................................................13

4.2. DESIGN CALCULATIONS FOR PARTICULAR COMPONENTS ..................................................14

4.2.1. CHOICE OF ANTI-FRICTION BEARINGS.............................................................................144.2.1.1. THEORETICAL LIFE ................................................................................................................. 144.2.1.2. MEAN LOADING OF BEARINGS SUBJECTED TO TYPE SM LOADS........................................ 14

4.2.1.2.1. Determination of the mean load SM mean on anti-friction bearings for combined motions....... 144.2.1.3. MEAN LOADING OF BEARINGS SUBJECTED TO TYPE SR LOADS ........................................ 154.2.1.4. MEAN LOADING OF BEARINGS SIMULTANEOUSLY SUBJECTED TO TYPE SM AND TYPESR LOADS............................................................................................................................................ 15

4.2.2. CHOICE OF ROPES.................................................................................................................154.2.2.1. CHOICE OF ROPE DIAMETER .................................................................................................. 16

4.2.2.1.1. Common bases for the two methods ................................................................................. 164.2.2.1.2. Method using the minimum practical factor of safety Zp ...................................................... 174.2.2.1.3. C-factor method ................................................................................................................ 18



4 - 2

4.2.3. CHOICE OF PULLEYS, DRUMS AND ROPE ATTACHMENT MEANS.............................194.2.3.1. MINIMUM WINDING DIAMETER................................................................................................. 19

4.2.3.1.1. Values of H....................................................................................................................... 204.2.3.1.2. Note.................................................................................................................................. 20

4.2.3.2. RADIUS OF THE BOTTOM OF THE GROOVE.......................................................................... 204.2.3.3. ROPE ATTACHMENT MEANS.................................................................................................. 21

4.2.4. CHOICE OF RAIL WHEELS ....................................................................................................214.2.4.1. RAIL WHEEL SIZE ................................................................................................................... 21

4.2.4.1.1. Determining the mean load ............................................................................................... 224.2.4.1.2. Determining the useful rail width b..................................................................................... 224.2.4.1.3. Determining the limiting pressure PL................................................................................... 234.2.4.1.4. Determining the coefficient c1 ............................................................................................ 244.2.4.1.5. Determining the coefficient c2 ............................................................................................ 25

4.2.4.2. NOTES..................................................................................................................................... 25

4.2.5. DESIGN OF GEARS..................................................................................................................26

APPENDIX..................................................................................................................................................27

A- 4.1.3. - DETERMINATION OF PERMISSIBLE STRESSES IN MECHANISMCOMPONENTS SUBJECTED TO FATIGUE....................................................................................27

EXAMPLE OF APPLICATION................................................................................................................. 30LIST OF SOME WORKS DEALING WITH FATIGUE PROBLEMS............................................................ 32

A- 4.2.2. - COMMENTS ON THE CHOICE OF ROPES AND ON THE PROBLEM OF THEFACTOR OF SAFETY...........................................................................................................................33

A- 4.2.3. - CONSIDERATIONS ON THE DETERMINATION OF MINIMUM WINDINGDIAMETERS FOR ROPES..................................................................................................................37



4 - 3

4.1. CALCULATION PROCEDURE

Mechanism components are designed by checking that they offer adequate safety against failuredue to fracture, crippling, fatigue or excessive wear.

Other factors must also be taken into consideration and it is particularly important to avoidoverheating or deflection which could interfere with correct functioning of the mechanism.

4.1.1. CHECKING FOR ULTIMATE STRENGTH 1

Mechanism components are checked for ultimate strength by verifying that the calculated stressdoes not exceed a permissible stress dependent on the breaking strength of the material used.

4.1.1.1. VALUE OF THE PERMISSIBLE STRESS

The value of the permissible stress σa is given by the following formula :

σa = σR / νR

where :

σR is the ultimate stress for the material

νR is a safety coefficient corresponding to each case of loading (clause 2.3.)

1 It might seem logical to check against the elastic limit, in line with the structures booklet, as this figure is, inprinciple, the limit not to be exceeded in the use of a material. The steels normally used for structures have awide gap between the yield strength and the ultimate strength and this gap affords protection against suddenfailure even when the yield strength is considerably exceeded.On the other hand, the use in mechanisms of certain steels with a very high, elastic limit as compared to theultimate strength would result in fragile parts being produced if the permissible limit stress were to be basedon the elastic limit, and any accidental overstepping of this limit would lead to immediate failure. This explainswhy the ultimate strength is chosen as the criterion for verification.



4 - 4

4.1.1.2. VALUES OF THE COEFFICIENT ννννR

The values to be adopted for νR are given in table T.4.1.1.2.

Table T.4.1.1.2. Values of ννννR

Cases of loading I and II III

Value of νR 2,2 1,8

In the case of grey cast iron, the values of νR are to be amplified by 25 %.

4.1.1.3. RELATIONS BETWEEN THE CALCULATED STRESSES AND THE PERMISSIBLESTRESSES

According to the type of loading considered, the following relations must be verified in which :

σt is the calculated tensile stress

σc is the calculated compressive stress

σf is the calculated bending stress

τ is the calculated shear stress.

1) Pure tension : 1,25 . σt ≤ σa

2) Pure compression : σc ≤ σa

3) Pure bending : σf ≤ σa

4) Combined bending and tension : 1,25 . σt + σf ≤ σa

5) Combined bending and compression : σc + σf ≤ σa

6) Pure shear : 30,5 τ ≤ σa

7) Combined tension, bending and shear : [ ( 1,25 . σt + σf )2 + 3 τ2 ]0,5 ≤ σa

8) Combined compression, bending and shear : [ ( σc + σf )2 + 3 τ2 ]0,5 ≤ σa



4 - 5

4.1.2. CHECKING FOR CRIPPLING

Parts subject to crippling are designed in compliance with clause 3.3. for booklet 3, checking thatthe calculated stress does not exceed a limit stress determined as a function of the criticalstress above which there is a risk of crippling occurring.

For this check, the coefficient γm is taken into account, its value depending on the group in whichthe mechanism is classified (see table T.2.6.)

Some general considerations relating to the checking of parts for crippling are given in appendixA-3.3.

4.1.3. CHECKING FOR FATIGUE

4.1.3.1. GENERAL METHOD

The fatigue strength of a given component is mainly determined by :

- the material from which the component is constructed ;

- the shape, surface condition, state of corrosion, size (scale effect) and other factorsproducing stress concentration ;

- the ratio κ between the minimum and maximum stresses which occur during the variousstress cycles ;

- the stress spectrum ;

- the number of stress cycles.

The fatigue strength of a mechanical component is known only in exceptional cases. Generallyspeaking, it is to be derived from the characteristics of the material and of the component andfrom accepted laws concerning their behaviour.

The starting point is provided by the endurance limit under alternating tensile fatigue loading( κ = - 1) of a polished specimen, made from the material under consideration. The diminution ofthis fatigue strength as a result of the geometric shape of the piece, its surface condition, itsstate of corrosion and its size is allowed for by introducing appropriate factors.From the endurance limit under alternating loading the corresponding limit with respect to otherratios κ between extreme stresses is obtained with the aid of a SMITH diagram, in which certainhypotheses are made as to the shape of the strength curve.

The endurance limit thus determined for the actual component, and with respect to a given ratioκ between extreme stresses, is taken as the basis for the plotting of the WÖHLER curve,concerning which certain hypotheses are also made. From this WÖHLER curve (fatigue strength



4 - 6

under the effect solely of stress cycles, all having the same ratio κ between extreme stresses),the PALMGREN-MINER hypothesis on fatigue damage accumulation can be used to determinethe fatigue strength of a component according to a group in which the component is classified.

The method described in 4.1.3. for determining the fatigue strength is applicable only tocomponents in which the structure of the material is homogenous over the entire section beingconsidered. It cannot, therefore, be used in the case of components which have undergone asurface treatment (e.g. hardening, nitriding, casehardening). In such cases the fatigue strengthcan be derived from the WÖHLER curve only if the latter has itself been determined with respectto components which have been made from the same material, have a comparable shape andsize and have undergone exactly the same surface treatment.

Checking for fatigue strength only needs to be performed for case of loading I.

Where the number of stress cycles is less than 8 000, such checking is not necessary.

4.1.3.2. ENDURANCE LIMIT UNDER ALTERNATING LOADING OF A POLISHED SPECIMEN

The specialised works on the subject (see also appendix A-4.1.3.) provide the endurance limitvalue σbw under alternating rotational bending of a polished specimen in the case of materialsused regularly in construction of mechanisms.

By approximation, the same values of σbw may be accepted for the endurance limit underalternating rotary bending.

To obtain the endurance limit under alternating axial tension and compression, the values of σbw

have to be decreased by 20 % 2.

2 An element of material, when subjected to the same stress as an adjacent element, supports the latter lesseffectively than if it were subjected to a lower stress, as is the case with bending. A stress gradient, i.e. :

( difference in stress between two adjacent elementary parts )( distance between these two elementary parts )

which is higher, produces a strengthening effect.



4 - 7

The endurance strength τw under alternating shear (pure shear or torsion) is derived from σbw bythe relation :

τw = σbw / 30,5

The values given for σbw are generally those corresponding statistically to a 90 % survivalprobability. In the case of carbon steels in common use in mechanisms, it is permissible toadopt :

σbw = 0,5 . σR

σR being the minimum ultimate strength.

4.1.3.3. INFLUENCE OF THE SHAPE, SIZE, SURFACE CONDITION AND CORROSION

The shape, size, surface condition (machining) and state of corrosion of the component underconsideration entail a decrease in the endurance limit under alternating loading in relation to theideal case of a polished specimen.

This influence is allowed for by introducing factors ks, kd, ku and kc respectively, concerning thedetermination of which, directions will be found in appendix A-4.1.3.

The endurance limit under alternating loading σwk or τwk of the component under consideration isgiven for tension, compression, bending and torsional shear by the relation :

σwk = σbw / ( ks . kd . ku . kc )or

τwk = τw / ( ks . kd . ku . kc )

In the case of pure shear we take :τwk = τw4.1.3.4. ENDURANCE LIMIT AS A FUNCTION OF κ, σR AND σwk (or τwk)

Fig. 4.1.3.4. expresses, in the form of a SMITH diagram, the hypotheses made concerning therelations between the endurance limit σd (or τd), the ratio κ between extreme stresses, the tensile

strength σR and the endurance limit under alternating loading σwk (or τwk)

This gives the following relations :

Normal stresses :

-1 ≤ κ < 0 Alternating stresses

σd = 5 . σwk / ( 3 - 2 . κ )

0 ≤ κ < 1 Pulsating stresses

σd = [ 5 . σwk / 3 ] / 1 - [(1 - 5 . σwk / ( 3 . σR )) . κ ]



4 - 8

Shear stresses :

-1 ≤ κ < 0 Alternating stresses

τd = 5 . τwk / ( 3 - 2 . κ )

0 ≤ κ < 1 Pulsating stresses

τd = [ 5 . τwk / 3 ] / 1 - [(1 - 5 . 30,5 . τwk / ( 3 . σR )) . κ ]

Tension,Compression

Shear

Average

or

or

Figure 4.1.3.4.



4 - 9

4.1.3.5. WÖHLER CURVE

"WÖHLER curve" in this context means an endurance curve representing the number n of stresscycles which can be withstood before fatigue failure, as a function of the maximum stress σ (T),

when all stress cycles present the same amplitude and the same ratio κ between extremevalues.

With regard to this WÖHLER curve, the following hypotheses are made respectively :

- for n = 8 * 103 :σ = σR

orτ = σR / 30,5

- for 8 * 103 ≤ n ≤ 2 * 106 , the area of limited endurance, the function is represented by a straightfine TD in a reference system comprising two logarithmic scale axes (figure 4.1.3.5.)

The slope of the WÖHLER curve, in the interval considered, is characterised by the factor :

c = tan( ϕ ) = [ log(2 * 106 ) - log(8 * 103 ) ] / ( log σR - log σd )or

c = tan( ϕ ) = [ log(2 * 106 ) - log(8 * 103 ) ] / [ ( log ( σR / 30,5 ) - log τd ) ]

- for n = 2 * 106 :σ = σd

orτ = τd

- for n > 2 * 106 , the so-called region of endurance limit, the function is represented, in thesame reference system as above, by the straight fine DN, bisector of the angle formed by theextension of TD and a fine parallel to the axis of the n values, passing through D.

The slope of the WÖHLER curve for n > 2 * 106 is characterised by the factor :

c’ = tan( ϕ‘ ) = c + ( c2 + 1 )0,5



4 - 10

Figure 4.1.3.5.

The spectrum factor ksp of the component is determined by means of the above mentioned valueof c. In the case of certain components in group E8 (see 4.1.3.6.), the calculation must also beperformed in exactly the same way, but after replacing c by c'. To distinguish between the twospectrum factors thus found, the second will be designated k’sp .

A c value below 2,5 is an indication of faulty design of the component concerned. Such acomponent must not be put into service.



4 - 11

4.1.3.6. FATIGUE STRENGTH OF A MECHANICAL COMPONENT

The fatigue strength σk or τk of a given mechanical component is determined by the followingexpressions respectively :

σk = 2[ ( 8 - j ) / c ] . σd

orτk = 2[ ( 8 - j ) / c ] . τd

where j is the component's group number.

In the case of group E8 components, of which the total duration of use n and the spectrum factork'sp (see 4.1.3.5.) satisfy the inequality :

n . k'sp > 2 * 106

σk or τk must, however, be determined by the expression :

σk = [ (2 * 106 / n ) . ( 1 / k'sp ) ]1/c’ . σd

orτk = [ (2 * 106 / n ) . ( 1 / k'sp ) ]

1/c’ . τd

The group classification of components, on the basis of their total duration of use n and theirspectrum factor ksp, as well as the critical fatigue stresses associated with each group, areillustrated in figure 4.1.3.6. where σjk represents the stress applying to group Ej. For the critical

shear stresses, the letter σ must be replaced by τ.

4.1.3.7. PERMISSIBLE STRESSES AND CALCULATIONS

The permissible stresses σaf and τaf are obtained by dividing the stresses σk and τk, defined in

4.1.3.6., respectively by a safety factor νk.

One takes :νk = 3,21/c

orνk = 3,21/c’ for group E8 components satisfying

the inequality in the penultimate paragraph of 4.1.3.6.

σaf and τaf will therefore be obtained by the relations :

σaf = σk / νk

τaf = τk / νk



4 - 12

and one verifies that :σ ≤ σaf

τ ≤ τaf

with :σ maximum calculated normal stress ;

τ maximum calculated shear stress.

Figure 4.1.3.6.

In the case of components acted upon simultaneously by normal stresses and shear stresseswith different ratios κ between extreme stresses, the following condition must be satisfied :

( σx / σkx )2 + ( σy / σky )

2 - [ σx . σy / ( σkx . σky ) ] + (τ / τk )2 ≤ 1,1 / νk

2

in which :

σx, σy = maximum normal stresses in the directions x and y respectively ;

τ = maximum shear stress ;

σkx , σky = fatigue strength for normal stresses, in the directions x and y respectively ;



4 - 13

τk = shear fatigue strength.

If it is not possible to determine the most unfavourable case of the foregoing relation from thecorresponding stresses σx, σy and τ, calculations must be performed separately for the loads σx

max, σy max and τmax and the most unfavourable corresponding stresses.

It should be noted that the checks described above do not guarantee safety against brittlefracture. Such safety can be ensured only by a suitable choice of material quality.

4.1.4. CHECKING FOR WEAR

In the case of parts subjected to wear, the specific physical quantifies which affect this, such asthe surface pressure or the circumferential velocity must be determined. The figures must besuch that, on the basis of present experience, they will not lead to excessive wear.



4 - 14

4.2. DESIGN CALCULATIONS FOR PARTICULAR COMPONENTS

4.2.1. CHOICE OF ANTI-FRICTION BEARINGS

To select anti-friction bearings, it is first necessary to check that the bearing is capable ofwithstanding :

- the static load to which it can be subjected under whichever of loading cases I, II or III is themost unfavourable, and

- the maximum dynamic load in the more unfavourable of loading cases I or II.

4.2.1.1. THEORETICAL LIFE

In addition, anti-friction bearings must be selected to give an acceptable theoretical life in hours(see table T.2.1.3.2.) as a function of the class of operation of the mechanism under a constantmean load as defined in clauses 4.2.1.2. and 4.2.1.3. below.

4.2.1.2. MEAN LOADING OF BEARINGS SUBJECTED TO TYPE SM LOADS

In order to allow for variations in the loads of type SM during the cycles of operation, an equivalentmean loading SM mean is determined which is supposed to be applied constantly during thetheoretical life determined by clause 4.2.1.1.

SM mean is obtained by multiplying SM max II 3 , defined by clause 2.6.4.1. and 2.6.4.2., by the cube

root of the spectrum factor km defined in 2.1.3.3.

SM mean = km . SM max II (1)

4.2.1.2.1. Determination of the mean load SM mean on anti-friction bearings for combined motions

In the case of motions which combine an elevation of the centre of gravity of the moving masseswith a horizontal displacement (e.g. unbalanced luffing), the mean load SM mean is determined bycombining :

- the mean load due to the accelerations and the effect of the wind, as determined by applyingclause 4.2.1.2. with,

3 or SM max I for components not subjected to wind.



4 - 15

- the mean load due to the vertical displacement of the centre of gravity of the moving masses,as determined from the expression :

SM mean = ( 2 . SM max + SM min ) / 3

where SM max and SM min are the maximum and minimum values of the corresponding loads.

4.2.1.3. MEAN LOADING OF BEARINGS SUBJECTED TO TYPE SR LOADS

The extreme loads SR max and SR min developed in loading case I for appliances not subjected towind or loading case II for appliances subjected to wind (see clause 2.6.) are considered andthe bearing is designed for a constant mean load given by the expression :

SR mean = ( 2 . SR max + SR min ) / 3

and applied for the theoretical life in accordance with clause 4.2.1.1.

4.2.1.4. MEAN LOADING OF BEARINGS SIMULTANEOUSLY SUBJECTED TO TYPE SM AND TYPESR LOADS

On the basis indicated above the equivalent mean loads are determined for each of the type SM

and SR loads, assumed to be acting alone and the bearing is selected for an equivalent meanload resulting from combination of the two mean loads SM and SR.

4.2.2. CHOICE OF ROPES

The following rules aim at defining reasonable minimum requirements for the choice of ropesused on hoisting appliances covered by these Design Rules.

They do not purport to resolve all the problems nor to serve as a substitute for the dialogue whichis essential between the rope manufacturer and the manufacturer of hoisting appliances.

They apply to preferred ropes conforming to ISO Recommendation 2408 : "Steel ropes forgeneral use - Characteristics".

They do not exclude, however, ropes which are not specified in ISO Recommendation 2408.

For such ropes, it is incumbent upon the rope manufacturer to validate for the user the minimumvalues of parameters detailed in the ISO Recommendation.

The terminology of the rope parameters complies with that used in ISO Recommendation 2408.



4 - 16

The methods stated hereafter assume that the ropes are greased correctly, that the windingdiameters of the pulleys and the drums are suitably selected in compliance with 4.2.3. and that,when in service, the ropes are properly maintained, inspected and periodically replaced inconformity with ISO Recommendation 4309 "Rope inspection"

The selection of rope diameter (and winding diameters in 4.2.3.) is based on the group of thehoisting mechanism. However, for appliances which require frequent dismantling (such asbuilders tower cranes), in which ropes have to be changed more frequently, it is permissible toselect a hoist rope from the group immediately below that of the hoisting mechanism but notinferior to group M3.

Whenever hoisting appliances are used for dangerous handling operations (e.g. molten metal,highly radioactive or corrosive products, etc.) the choice of the ropes and pulleys must takeaccount of the mechanism group next above that resulting from the normal classification of thehoisting appliances.

Group M5 is the minimum group to be used for the handling of dangerous loads for the choice ofrope and pulley diameters.

4.2.2.1. CHOICE OF ROPE DIAMETER

Two methods can be used at the choice of the manufacturer :

- the method using the minimum practical factor of safety Zp (see 4.2.2.1.2.) which is valid forrunning ropes and static ropes (guy ropes, stays, etc.).

- the C factor method (4.2.2.1.3.) applicable to running ropes only.

4.2.2.1.1. Common bases for the two methods

4.2.2.1.1.1. Definition of the maximum tensile force S in the hoist rope (grab ropes excepted)

This is obtained by taking account of the following factors :

- maximum safe working load of the appliance,

- weight of the pulley block and the hoist accessories, the dead weights of which are added tothe load effect so as to increase the rope tension,

- mechanical demultiplication due to the rope reeving,

- efficiency of the rope reeving,

- loads due to accelerations if they exceed 10 % of the vertical loads,

- rope inclination at the upper extreme position if the angle of the rope with the hoist axisexceeds 22,5°.



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4.2.2.1.1.2. Definition of the maximum tensile force S in ropes other than hoist ropes

The determination of the maximum tensile force S in the various ropes which are not exclusivelyused for the vertical hoisting of loads is based on the loads determined in load cases I or IItaking account of the most unfavourable case which can occur repeatedly in normal use.

For ropes which produce horizontal movement of loads, account must be taken of the loadingresulting from rolling motion and friction, together with the maximum inclination that the support,on which the load is moved, can assume locally under the influence of the normal loading.

4.2.2.1.1.3. Determination of the maximum tensile force S in the ropes of multirope grabs (holding and closing)

In the case of appliances with grabs, where the weight of the load is not always equallydistributed between the closing ropes and the holding ropes during the whole of a cycle, thevalue of S to be applied should be determined as follows :

1) If the system used automatically ensures an equal distribution of the hoisted load betweenthe closing and holding ropes, or any difference between the loads carried by the ropes islimited to a short period at the end of closing or at the beginning of opening, S should bedetermined as follows :

a) closing ropes : S = 66 % of the weight of the loaded grab, divided by the number ofclosing ropes.

b) holding ropes : same pourcentage.

2) If the system used does not automatically secure an equal distribution of the load betweenthe closing ropes and the holding ropes during the hoisting motion and, in practice, almostall the load is applied to the closing ropes, S should be determined as follows :

a) closing ropes : S = total weight of the loaded grab divided by the number of closingropes.

b) holding ropes : S = 66 % of the total weight of the loaded grab divided by the number ofholding ropes.

4.2.2.1.2. Method using the minimum practical factor of safety Zp

Definitions

The minimum practical factor of safety Zp is the ratio between :

- the minimum breaking load F0 of the rope (minimum load which must be attained whencarrying out the rope breaking test),



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- and the maximum tensile force S in the rope

Zp = F0 / S

4.2.2.1.2.1. Rope selection

The chosen rope must have a minimum practical factor of safety at least equal to the minimumvalue Zp for the mechanism group to which the rope in question belongs (see table T.4.2.2.1.2.).

Table T.4.2.2.1.2. - Factor of safety Zp

Group of Minimum value Zp

mechanism Running ropes Static ropesM 1M 2M 3M 4M 5M 6M 7M 8

3,153,353,55

44,55,67,19

2,52,53

3,54

4,555

4.2.2.1.3. C-factor method

Definitions :

C = rope selection factor,

S = maximum tensile force exerted on the rope when in use,

d = nominal diameter of the rope (dimension by which the rope is designated),

f = fill factor of the rope,

k = spinning loss factor due to the rope construction,

RO = minimum ultimate tensile stress of the wire composing the rope,

K' = empirical factor for the minimum breaking load for a given rope construction such that

k’ = π / 4 .f . k



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4.2.2.1.3.1. Rope selection

For a rope of a given construction, having a given minimum steel strength, and for a givenmechanism group there is a factor C which is expressed by the formula :

C = [ Zp / (π . k . f . RO / 4 ) ]0,5 = [ Zp / (k’ . RO ) ]0,5

where Zp is the minimum value for running ropes in table T.4.2.2.1.2., corresponding to themechanism group chosen for the rope.

The nominal diameter must be such that : d ≥ C . S0,5

4.2.2.1.3.2. Calculation of the factor C - guarantees

The values of C are calculated taking account of :

- the factor Zp corresponding to the mechanism group,

- the breaking strength under tension of the steel of the rope wires,

- the factor k' (or factors k and f) which can either :• be taken from ISO Recommendation 2048 for normal ropes covered therein (see

Appendix),• or be guaranteed by the rope manufacturer if the rope is of a special construction. In this

case, the certificate supplied by the rope manufacturer must clearly state the guaranteedvalues of k'.

4.2.3. CHOICE OF PULLEYS, DRUMS AND ROPE ATTACHMENT MEANS

4.2.3.1. MINIMUM WINDING DIAMETER

The minimum winding diameter for the rope is determined by checking the relationship :

D ≥ H . d

where :

D is the winding diameter on pulleys, drums or compensating pulleys measured to the axis ofthe rope.

H is a coefficient depending upon the mechanism group.

d is the nominal diameter of the rope.

Note - Refer to 4.2.2. for the mechanism group in which the rope should be classified.



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4.2.3.1.1. Values of H

The minimum values of the coefficient H, depending upon the group in which the mechanism isclassified, are given in table T.4.2.3.1.1. for drums, pulleys and compensating pulleys.

They correspond to ropes currently used and known and are based on experience concerningtheir working conditions.

They do not however serve as a substitute for the dialogue which is indispensable between therope manufacturer and the manufacturer of hoisting appliances, especially when the use of newropes with varying flexibility characteristics is being considered.

Table T.4.2.3.1.1. Values of H

Mechanismgroup Drums Pulleys

Compensatingpulleys

M 1M 2M 3M 4M 5M 6M 7M 8

11,212,514161820

22,425

12,514161820

22,42528

11,212,512,51414161618

4.2.3.1.2. Note

When the formula given in clause 4.2.2.1. has been used to determine a minimum ropediameter from which in turn the minimum diameters for drums and pulleys have beendetermined, a rope of diameter greater than the minimum calculated diameter can be used withthese latter diameters, provided that the diameter of the rope used does not exceed theminimum diameter by more than 25 % and that the pull in the rope does not exceed the value Sused for calculating this minimum diameter.

4.2.3.2. RADIUS OF THE BOTTOM OF THE GROOVE

The useful life of the rope depends not only on the diameter of the pulleys and drums, but alsoon the pressure exerted between the rope and the groove supporting the rope.

The winding ratios above are given on the assumption of a radius of supporting groove r where :r = 0,53 . d

d being the nominal diameter of the rope.



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4.2.3.3. ROPE ATTACHMENT MEANS

Rope attachments must be so designed as to withstand a tensile force 2,5 times the maximumtensile force S without showing permanent deformation.

The means attaching the rope to the drum must be of such a design that, taking account of thefriction of the turns which remain around the drum, the sum of the frictional and fixing forceswithstands a tensile force 2,5 times the maximum tensile force S.

The coefficient of friction between the rope and the drum used in the calculations shall be :

µ = 0,1

when the rope is completely unwound from the drum, at least two complete turns of rope mustremain on the drum before the rope end attachment.

4.2.4. CHOICE OF RAIL WHEELS

In order to choose a rail wheel, its diameter is determined by considering :

- the load on the wheel,

- the quality of the metal from which it is made,

- the type of rail on which it rues,

- the speed of rotation of the wheel,

- the group classification of the mechanism.

4.2.4.1. RAIL WHEEL SIZE

To determine the size of a rail wheel, the following checks must be made :

- that it is capable of withstanding the maximum load to which it will be subjected, and

- that it will allow the appliance to perform its normal duty without abnormal wear.

The two requirements are checked by means of the following two formulae :

Pmean III ≤ PL . C1max . C2max < 1,38 . PL ≈ 1,4 PL

taking C1max = 1,2 and C2max = 1,15

and Pmean I, II / ( b . D ) ≤ PL . C1 . C2



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where :

D is the wheel diameter in mm

b the useful width of the rail in mm

PL a limiting pressure dependent upon the metal used for the wheel, in N/mm2

C1 a coefficient depending on the speed of rotation of the wheel

C2 is a coefficient depending on the group of the mechanism

Pmean III is the mean load to be withstood by the wheel, in loading case III, in N, calculatedaccording to the formulae in clause 4.2.4.1.1.

Pmean I,II is the mean load in case I or II.

4.2.4.1.1. Determining the mean load

In order to determine the mean loads, the procedure is to consider the maximum and minimumloads withstood by the wheel in the loading cases considered, i.e. with the appliance in normalduty but omitting the dynamic coefficient ψ when determining Pmean I,II and with the appliance notin use for Pmean III .The values of Pmean are determined by the formula below in the three cases ofloading I, II and III :

Pmean I,II,III = ( Pmin I,II,III + 2 . Pmax I,II,III ) / 3

4.2.4.1.2. Determining the useful rail width b

For rails having a flat bearing surface and a total width l with rounded corners of radius r at eachside, we have:

b = l - 2 . r

for rails with a convex bearing surface, we have:b = l - 4 . r / 3 4

4 (1) For the same width of rail head, these formulae give a greater useful bearing width forconvex rails than for flat rails. This allows for the superior adaptation of a slightly convex rail to therolling motion of the wheel.



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4.2.4.1.3. Determining the limiting pressure PL

The value of PL is given in table T.4.2.4.1.3. as a function of the ultimate strength of the metal ofwhich the rail wheel is made;

Table T.4.2.4.1.3. - Values of PL

Ultimate strength for metal PL

used for rail wheel in N/mm2

σR > 500 N/mm2 5,0

σR > 600 N/mm2 5,6

σR > 700 N/mm2 6,5

σR > 800 N/mm2 7,2

The qualifies of metal refer to cast, forged or rolled steels, and spheroidal graphite cast iron.

In the case of rail wheels with tyres, consideration must obviously be given to the quality of thetyre, which should be sufficiently thick not to roll itself out.

In the case of wheels made of high tensile steel and treated to ensure a very high surfacehardness, the value of PL is limited to that for the quality of the steel composing the wheel prior tosurface treatment, according to table T.4.2.4.1.3., since a higher value would risk causingpremature wear of the rail.

For a given load, however, wheels of this type have a much longer useful life than wheels oflesser surface hardness, which makes their use worthwhile in the case of appliancesperforming intensive service.

Alternatively, it is possible to use wheels of ordinary cast iron, especially chilled cast iron, whichhas good surface hardness.

It must be remembered that such wheels are brittle and that their use should be avoided for highspeed motions or when shock loadings are to be feared.

When these are used their diameter is determined by taking PL equal to 5 N/mm2.



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4.2.4.1.4. Determining the coefficient c1

The values of c1 depend on the speed of rotation of the wheel and are given in table T.4.2.4.1.4.a.

These same values are also given in table T.4.2.4.1.4.b. as a function of the wheel diameter andthe speed in m/min.

Table T.4.2.4.1.4.a. - Values of c1

Wheel rotationspeed in R.P.M. c1



2001601251121009080716356

0,660,720,770,790,820,840,870,890,910,92

504540

35,531,52825

22,42018

0,940,960,970,991,001,021,031,041,061,07

1614

12,511,2108

6,35,65

1,091,101,111,121,131,141,151,161,17

Table T.4.2.4.1.4.bValues of c1 as a function of the wheel diameter and the speed of travel

wheeldiameter Values of c1 for travel speeds in m/min

in mm 10 12,5 16 20 25 31,5 40 50 63 80 100 125 160 200 250200250315400500630710800900

1 0001 1201 250

1,091,111,131,141,151,17

------

1,061,091,111,131,141,151,161,17

----

1,031,061,091,111,131,141,141,151,161,17

--

11,031,061,091,111,131,131,141,141,151,161,17

0,971

1,031,061,091,111,121,131,131,141,141,15

0,940,97

11,031,061,091,11,111,121,131,131,14

0,910,940,97

11,031,061,071,091,11,111,121,13

0,870,910,940,97

11,031,041,061,071,091,11,11

0,820,870,910,940,97

11,021,031,041,061,071,09

0,770,820,870,910,940,970,99

11,021,031,041,06

0,720,770,820,870,910,940,960,970,99

11,021,03

0,660,720,770,820,870,910,920,940,960,970,99

1

-0,660,720,770,820,870,890,910,920,940,960,97

--

0,660,720,770,820,840,870,890,910,920,94

---

0,660,720,770,790,820,840,870,890,91



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4.2.4.1.5. Determining the coefficient c2

The coefficient c2 depends on the group classification of the mechanism and is given in tableT.4.2.4.1.5.

Table T.4.2.4.1.5. - Values of c2

Group classificationof mechanism c2

M 1 to M 4M 5M 6

M 7 - M 8

1,121,000,900,80

4.2.4.2. NOTES

Note 1

The formulae apply only to wheels whose diameters do not exceed 1,25 m. For larger diametersexperience shows that the permissible pressures between the rail and the wheel must belowered. The use of wheels of greater diameter is not recommended.

Note 2

It should be noted that the limiting pressure PL is a notional pressure determined by supposingthat contact between the wheel and the rail takes place over a surface whose width is the usefulwidth defined earlier (clause 4.2.4.1.2.) and whose length is the diameter of the wheel. Themethod of calculating set out above is derived from application of the HERTZ formula, which maybe written :

σcg2 / ( 0,35 . E ) = P / ( b . D )

where :

σcg is the compressive stress in the wheel and the rail N/mm2

E the modulus of elasticity of the metal in N/mm2

P the wheel load in N

b and D in mm, being as defined above (clause 4.2.4.1.).

Taking KL to represent the value σcg2 / ( 0,35 . E ) which has the dimension of a pressure in

N/mm2 , the relation may be written :KL = P / ( b . D )



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and characterizes the wheel pressure on the rail. The formula of clause 4.2.4.1. is obtained byputting :

KL = PL . c1 . c2

4.2.5. DESIGN OF GEARS

The choice of the method of making design calculations for gears is left to the manufacturer, whomust indicate the origin of the method adopted, the loads to be taken into account beingdetermined in accordance with the directions given in 2.6.

In the case of a calculation which takes account of the operating time the conventional hoursdetermined in 2.1.3.2. should be used.



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APPENDIX

A- 4.1.3. - DETERMINATION OF PERMISSIBLE STRESSES IN MECHANISMCOMPONENTS SUBJECTED TO FATIGUE

The endurance limit for a polished specimen is a laboratory value, which is practically neverattained in parts actually used. Numerous factors - shape, size, surface condition (machiningquality) and possible corrosion - induce discontinuities resulting in "notch effects", whichdecrease the permissible stresses in the part, when these stresses are calculated byconventional elementary methods for the strength of materials. These factors are taken intoaccount by coefficients, called ks, kd, ku, kc, respectively all greater than or equal to unity, by theproduct of which the endurance limit for a polished specimen is devided.

Guidelines concerning the determination of these coefficients are set out below :

a. Determination of ks

This coefficient specifies the stress concentrations caused by changes of section with radii,annular grooves, transverse holes and the method of securing hubs.

Figures A.4.1.3.1. a. and b. give the values of the shape coefficient ks as a function of the ultimatestrength of the metal, valid for diameter D of 10 mm.

The curves a. give the coefficient ks for changes of section of ratio D/d = 2 with a correction tableT.A.4.1.3.1. for other values of D/d. The b curves give, for guidance some values of ks for holes,annular grooves and keyways.

Diameters in excess of 10 mm are taken care of by introducing the size coefficient kd.

Figure A.4.1.3.1.a. Shape coefficient ks (Diameter D = 10 mm)Change of section D/d = 2



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For other values of D/d read ks from the curve (r/d) + q with the following values for q :

Table T.A.4.1.3.1. - Correction factors q for D/d ≤ 2

D/d 1,05 1,1 1,2 1,3 1,4 1,6 2q 0,13 0,1 0,07 0,052 0,04 0,022 0

Curve I Transverse hole d1 = 0,175 dII Annular groove : depth 1 mmIII Keyed hubIV Press-fitted hubFigure A.4.1.3.1.b. Shape coefficient ks (Diameter D =10 mm)

Hole, annular groove, keyway

b. Determination of size coefficient kd

For diameters greater than 10 mm the stress concentration effect increases and this increase isallowed for by introducing the size coefficient kd.

The values of the coefficient kd are given in table T.A.4.1.3.2. for values of d from 10 mm to 400mm.

Table T.A.4.1.3.2. - Values of kd

d mm 10 20 30 50 100 200 400kd 1 1,1 1,25 1,45 1,65 1,75 1,8



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c. Determination of surface condition (method of machining) coefficient ku

Experience shows that parts produced with a rough finish have a longer endurance limit thancarefully polished parts.

This is allowed for by applying a machining coefficient ku given in figure A.4.1.3.2. for the case ofa surface which is ground or finely polished with emery and for the case of a surface which isrough machined.

d. Determination of corrosion coefficient kc

Corrosion can have a very appreciable effect on the endurance limit of steels ; this is allowed forby applying a coefficient kc.

Figure A.4.1.3.2. gives the values of this coefficient kc for the cases of corrosion due to freshwater and due to sea water.

Figure A.4.1.3.2. - Values of the machining coefficient ku , corrosion coefficient kc

Values of ku

Curve I Surface ground or finely polishedII Surface rough machined

Values of kc

III Surface corroded by fresh waterIV Surface corroded by sea water



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EXAMPLE OF APPLICATION

Shaft in A-550 steel with change of section.Diameters D = 70 mm and d = 5D mmwith transition radius r = 5 mm.Turned on lathe, with keyed wheel.

The component will be deemed to be classified in group E4.

We shall assume alternating loading (κ = - 1) and the shaft to be of A 550 steel

(minimum σR = 550 N/mm2). We can therefore adopt :

σbw = 0,5 . 550 = 275 N/mm2

Section A-BD/d = 70 / 50 = 1,4r/d = 5 / 50 = 0,1

Determination of ks (shape)For D/d = 1.4 we have :

q = 0,04 (Table T.A.4.1.3.1.)

From the curve (r/d) + q = 0,1 + 0,14 we find by interpolation :

ks = 1,4 (Figure A.4.1.3.1.a.)

Determination of kd (size)For d = 50 we have :

kd = 1,45 (Table T.A.4.1.3.2.)

Determination of ku (machining)For a part turned on a lathe we have :

ku = 1,15 (Figure A.4.1.3.2., curve II)

From the foregoing values we derive :

σwk = 275 / ( 1,4 . 1,45 . 1,15 ) = 117,8 N/mm2



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For κ = - 1 we have :

σd = σwk = 117,8 N/mm2

c = log(2 000 000/8 000) / log(550 / 117,8) = 3,58

For group E4 the critical stress is therefore :

σk = σd . 2(8-4)/c = 117,8 . 2(4 / 3,58) = 255,4 N/mm2

The safety coefficient νk is given by :

νk = 3,21/c = 3,2(1 / 3.58) = 1,38

The permissible stress σaf is therefore :

σaf = 255,4 / 1,38 = 184,6 N/mm2

Section C-D

We have :

ks = 2,2 (Figure A.4.1.3.1.b.)

kd = 1,45 (same value as above)

ku = 1,15 (same value as above)

Hence :

σwk = 275 / ( 2,2 . 1,45 . 1,15 ) = 75,0 N/mm2

σd = σwk = 75,0 N/mm2

c =log(2 000 000 / 8 000) / log(550 / 75) = 2,77

σk = 75 . 2(4/2,77) = 204 N/mm2

νk = 3,21/2.77 = 1,52

σaf = 204 / 1,52 = 134 N/mm2



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LIST OF SOME WORKS DEALING WITH FATIGUE PROBLEMS

(1) Niemann, G. MaschinenelementeBand 1Springer Verlag Berlin/Gottingen/Heidelberg 1975

(2) Niemann, G. MaschinenelementeBand 2Springer Verlag Berlin/Gottingen/Heidelberg 1983

(3) Decker, K.-H. MaschinenelementeCarl Hanser Verlag, Munchen 1982

(4) "Metal Fatigue" by J.A. POPE - Ph D, D.Sc - Wh.Sch. I. Mech. E.Chapman and Hall Ltd., 37, Essex Street, London, W.C.2.

(5) "La Fatigue des Metaux" by R. CAZAUD - Ingenieur CNAM - Doctor of the University of ParisLecturer at the Higher Institute for Mechanical Engineering Materials, Consulting EngineerDunod92, rue Bonaparte - Paris

(6) "Fatigue of Metals and Structures" by H.J. GROVER, S.A. GORDON, R.L. JACKSONThames and HudsonLondon



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A- 4.2.2. - COMMENTS ON THE CHOICE OF ROPES AND ON THE PROBLEMOF THE FACTOR OF SAFETY

The useful life of a hoisting rope depends on factors inherent both in the construction of the rope(internal factors) and in the characteristics of the hoisting appliance and the way in which therope is reeved (external factors).

The main external factors are the tensile load, the pulley diameters and the type and number ofworking cycles.

These factors will in principle determine the rope winding diameters.

Figure F.A.4.2.2. shows the relationships between the tensile stress, the pulley diameters andthe useful life (number of bending reversals causing failure) for a given rope (of diameter 16mm).

According to this diagram, the larger the pulley diameter and the smaller the tensile stress, thelonger the useful life of the rope.

Winding diameters must be determined so as to ensure a reasonable useful life of the ropebefore its replacement.

The old method of calculation defined fixed minimum factors of safety and minimum windingdiameters (as a function of the rope diameter) for certain uses, such as for example in hoistingappliances.

This method, which is still used and sometimes even stipulated by law in many countries, doesnot enable the conditions for a reasonable useful life to be met. The loads and the type ofutilisation of hoisting appliance mechanisms differ considerably from one appliance to anotherwith the result that such minimum values may be too high in certain cases (e.g. for a powerstation overhead travelling crane) or too low in other cases (e.g. for a grabbing crane on arduousduty).

Even if the safety factors were chosen according to the group of the mechanisms, the calculationof winding diameters on the basis of these safety factors could not result in a good design for thefollowing reasons :

The manufacturer wishes to use ropes of the smallest possible diameter in order to obtain thesmallest possible diameters for the pulleys and drums. For a given safety factor, he achievesthis by using wire of the greatest possible strength and using a rope with the greatest possiblefill factor.



4 - 34

Yet the useful life of a rope whose diameter has been calculated in this way is not alwaysoptimum.

A rope of identical diameter, of which the wire is of longer strength (e.g. 1600 N/mm2 instead of2200 N/mm2) and the fill factor is lower (e.g. eight strands instead of six) may have a muchlonger useful life in spite of the lower factor of safety.

Another difficulty stems from the fact that the safety factor is related to breaking strengths whosedefinitions differ from one country to another, and safety factors do not have the same meaning ifthey relate to a breaking strength defined in different ways.

Four definitions exist for the breaking strength of ropes :

- Calculated breaking strength : this is the cross-section of the rope multiplied by the strengthof the wire of which it is composed ;

- Theoretical breaking strength : given by the sum of the breaking strengths of the wires usedin the rope ;

- Actual breaking strength : this is the load obtained by an ultimate tensile strength test on therope ;

- Nominal breaking strength : this is the minimum breaking strength guaranteed by the ropemanufacturer.

When a rope is determined by using a safety factor which is related either to the actual breakingstrength or to the nominal breaking strength, the manufacturer tends to adopt ropes in which thespinning loss (difference between the theoretical breaking strength and the actual breakingstrength) is as small as possible in order to obtain a smaller rope diameter. The spinning loss,however, is not related to the resistance of a rope to repeated bending. A satisfactory useful lifefor ropes cannot therefore be obtained with this method of calculation.

This shows that the safety factor is not an adequate basis for determining the winding diametersrequired to ensure satisfactory rope life under bending reversals ; indeed this method will oftenprevent the optimum solution from being obtained.

Because it is difficult for the manufacturer to allow for the influence of these different factors, it ispreferable to determine the rope diameter dmin simply as a function of the tensile load S, from theformula :

dmin = C . S0,5

where C is a coefficient depending solely on the group of the mechanism.



4 - 35

In cases where non rotating ropes are used (e.g. tower cranes in which the load is suspendedfrom a single part) and for dangerous handling operations (e.g. molten materials), the values ofC are increased above the normal values in order to compensate for the more unfavourable ropeconstruction or the greater risk.

The value of C, the safety factor Zp referred to the theoretical breaking strength and the rope fillfactor f (ratio of the metal cross section of the rope to the area of the circle circumscribing therope) are linked by the following relation :

C = [ Zp / (π . k . f .RO / 4 ) ]0,5

where RO is the ultimate strength (in N/mm2) of the wire used in the rope.

The values of C apply to ropes made with wire having a strength of 1600, 1800, 2000 or 2200N/mm2 .

where, exceptionally, use is made of a rope composed of wires with a strength of 1400 N/mm ,the rope diameter must be increased accordingly.

The rope manufacturer or crane maker must choose the composition and cross section of therope, for the calculated minimum diameter d, to suit the reeving conditions of the particular ropeand in the light of the latest technical progress.



4 - 36

Number of bending reversals required to cause failure (useful life)

Number of bending reversals

Tensilstress

Langs lay rope, diameter 16 mm, six strands of nineteen 1 mm dia. wires, Ro = 1400 N/mm2

Cast-iron pulleys with machined groove of radius r = 8,5 mm.Figure A.4.2.2.

Influence of pulley diameter D and tensile stress σσσσt on the useful life of a rope



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A- 4.2.3. - CONSIDERATIONS ON THE DETERMINATION OF MINIMUMWINDING DIAMETERS FOR ROPES

There are no absolute minimum pulley and drum diameters below which a rope could no longeroperate. Nor is there a required absolute minimum diameter for different types of rope.

The useful life of a rope is progressively reduced with decreasing pulley and drum diameters, ifother conditions remain unchanged.

Figure A.4.2.3. shows the pattern of behaviour of a particular rope.

In order to ensure an adequate useful rope life, the minimum winding diameters D must bedetermined, as a function of the group classification of the mechanism involved, from the formula:

D / d ≥ H

where d is the nominal rope diameter and H is a coefficient which is chosen according to thegroup in which the mechanism is classified and which becomes higher when the duty is morearduous.

The coefficient H is higher for pulleys than for drums because, in the course of a cycle ofoperations, the rope is subjected to twice as many bending reversals over a pulley (rope straight,rope bent, rope straight) as on a drum (rope straight, rope bent).

The coefficient H is lower for equalising pulleys because the rope undergoes fewer bendingreversals and the movement is normally very limited. Such pulleys must nonetheless bedimensioned with reference to the number of bending reversals.

Unfavourable winding conditions, e.g. reeving around several pulleys, reverse bends, or the useof non-rotating ropes whose construction is less favourable for bending reversals, must becompensated for by a suitable increase to ensure a useful rope life commensurate with thegroup classification of the mechanism.



4 - 38

Number of bending reversals required to cause failure (useful life)

Number of bending reversals

Pulley diameter

Ratio

Langs lay rope, diameter 16 mm, six strands of nineteen 1 mm dia. wires, σR = 1400 N/mm2

Cast-iron pulleys with machined groove radius r = 8,5 mm.

Figure A.4.2.3.Influence of pulley diameter D and tensile stress σσσσt on the useful life of a rope




SECTION I


F.E.M.

1.001 3rd EDITION

REVISED

1998.10.01


HOISTING APPLIANCES

B O O K L E T 5

ELECTRICAL EQUIPMENT

Revised in 2003

The total 3rd Edition revised comprises booklets 1 to 5 and 7 to 9

Copyright by FEM Section I Also available in French and German




Section I


F.E.M.

1.001

3rd EDITION

REVISED

1998.10.01

RULES FOR THE DESIGN OFHOISTING APPLIANCES

BOOKLET 5

ELECTRICAL EQUIPMENT

Revised in 2003

The total 3rd revised comprises booklets 1 to 5 and 7 to 9

Copyright by FEM Section 1




Booklet 5 - 1/ 35

The third edition of the "Rules for the design of hoisting appliances" dated 1987.10.01')included 8 booklets. An addition to this edition was compiled in 1998. This addition isincorporated in booklet 9, which also replaces booklet 6.

This booklet forms part of the "Rules for the design of hoisting appliances" 3rd editionrevised, consisting of 8 booklets:

Booklet 1 - Object and scope

Booklet 2 - Classification and loading on structures and mechanisms

Booklet 3 - Calculating the stresses in structures

Booklet 4 - Checking for fatigue and choice of mechanism components

Booklet 5 - Electrical equipment revised in 2003

Booklet 6 – Stability and safety against movement by the wind

Booklet 7 - Safety rules

Booklet 8 - Test loads and tolerances

Booklet 9 - Supplements and comments to booklets 1 to 8

NOTE: Booklet 9 must not therefore be used separately

Booklet 5 has been revised in 2003 to take into account various European standards.

The main modifications concern the following points:

5.3 Installation of cables and conductors

This clause has been re-arranged; the new version includes some parts of old 5.2 andreferences to

EN 60204-32

EN 60364-5-52

5.5 Limiting and indicating devices (old title "End limit switches")

This clause has been replaced by references to requirements coming from Europeanstandards on motor over speed protection

5.6 Type of control

The revision of this clause makes references to requirements coming from Europeanstandards on braking resistors of inverters



Booklet 5 - 2/ 35

5.7 Environment

The existing text has been deleted and replaced by the reference to EN 60204-32.

Clauses on EMC and on potentially explosive atmospheres have been introduced

5.8 Selection of motors

The revision of this clause introduced minor changes. A new clause 5.8.4. on inverter driveshas been added

5.9 to 5.11

The revision of this clause introduced minor changes. The reference to IEC 60034-1 hasbeen added.



Booklet 5 - 3/ 35

BOOKLET 5 - ELECTRICAL EQUIPMENT

5.1 FOREWORD..................................................................................................................................................................................... 5

5.2 POWER SUPPLY .......................................................................................................................................................................... 6

5.2.1. G E N E R A L.........................................................................................................................................................................................................................................................6

5.2.2. CUT-OUT AND S AFETY DEVICES..............................................................................................................................................................................................6

5.2.3. C O N D U C T O R B A R S, CABLE REELS AND FLEXIBLE CABLES ..........................................................................................................................6

5.3 INSTALLATION OF CABLES AND CONDUCTORS ................................................................................................................. 7

5.3.1. C A L C U L A T I O N O F C R O S S - S E C T I O N O F C O N D U C T O R S .....................................................................................................................................7

5.3.1.1. CALCULATION OF THE CROSS-SECTION IN RELATION TO THE ADMISSIBLE VOLTAGE DROP.........................7

5.3.1.2. CALCULATION OF THE MINIMUM CROSS-SECTION IN RELATION TO THE THERMAL CAPACITY OF THECONDUCTORS ...............................................................................................................................................................8

5.3.2. INSTALLATION C O N D I T I O N S.........................................................................................................................................................................................................9

5.4 ELECTRICAL PROTE CTIVE AND SAFETY EQUIPMENT..................................................................................................... 10

5.4.1. S A F E G U A R D I N G M O T O R S A G A I N S T O V E R H E A T I N G ..........................................................................................................................................10

5.4.2. S A F E G U A R D I N G WIRING...............................................................................................................................................................................................................10

5.4.3. S A F E G U A R D I N G AGAINST ABSENCE OR INVERSION OF PHASES ........................................................................................................10

5.4.4. ACTION OF SAF E T Y D E V I C E S...................................................................................................................................................................................................10

5.4.5. P R O T E C T I O N A G AINST THE EFFECTS OF L IGHTNING ......................................................................................................................................11

5.5 LIMITING AND INDICATING DEVICES..................................................................................................................................... 12

5.5.1. G E N E R A L R E Q U I R E M E N T S.........................................................................................................................................................................................................12

5.5.2. M O T O R O V E R S P E E D P R O T E C T I O N....................................................................................................................................................................................12

5.6 CONTROLS .................................................................................................................................................................................... 13

5.6.1. C O M P O N E N T S.........................................................................................................................................................................................................................................13

5.6.1.1. RELAYS AND CONTACTORS.......................................................................................................................... 13

5.6.1.2. RESISTOR UNITS.......................................................................................................................................... 13

5.6.2. C O N T R O L G E A R , L O C A T I O N , M O U N T I N G A N D E N C L O S U R E S.....................................................................................................................14

5.6.3. T Y P E O F C O N T R O L.............................................................................................................................................................................................................................145.6.3.1. ENERGISATION ............................................................................................................................................. 14

5.6.3.2. CAB CONTROL .............................................................................................................................................. 14

5.6.3.3. FLOOR CONTROL.......................................................................................................................................... 14

5.6.3.4. CABLE-LESS CONTROLS............................................................................................................................... 14

5.6.4. C O N T R O L O F M E C H A N I C A L B R A K E S.................................................................................................................................................................................15

5.6.4.1. SECOND BRAKE............................................................................................................................................ 15

5.7 ENVIRONMENT............................................................................................................................................................................. 16

5.7.1. POTENTIALLY E X P L O S I V E E N V I R O N M E N T S...............................................................................................................................................................16

5.7.2. E L E C T R O M A G N E TIC COMPATIB IL ITY................................................................................................................................................................................16

5.8 SELECTION OF MOTORS ........................................................................................................................................................... 17

5.8.1. CRITERIA FOR MOTOR SELECTION ( IEC 60034-1) .................................................................................................................................................17

5.8.1.1. REMARKS ON THE SELECTION OF MOTORS................................................................................................. 17

5.8.1.2. DEGREE OF PROTECTION (IEC 60034-5)........................................................................................................ 18

5.8.1.3. THERMAL CALCULATION OF THE MOTOR ..................................................................................................... 18

5.8.1.4. SQUIRREL CAGE MOTORS WITH DIRECT STARTING..................................................................................... 20



Booklet 5 - 4/ 35

5.8.1.5. POWER CORRECTION IN FUNCTION OF AMBIENT TEMPERATURE AND ALTITUDE........................................ 21

5.8.1.6. CYCLIC DURATION FACTOR AND NUMBER OF WORKING CYCLES PER HOUR.............................................. 22

5.8.2. M O T O R S F O R V E R T I C A L M O T I O N S.....................................................................................................................................................................................235.8.2.1. DETERMINATION OF REQUIRED TORQUE..................................................................................................... 23

5.8.2.2. CYCLIC DURATION FACTOR AND NUMBER OF CYCLES PER HOUR............................................................... 24

5.8.3. M O T O R S F O R H O R I Z O N T A L M O T I O N S.............................................................................................................................................................................25

5.8.3.1. DETERMINING THE NECESSARY TORQUE .................................................................................................... 25

5.8.3.2. CYCLIC DURATION FACTOR AND NUMBER OF CYCLES PER HOUR............................................................... 27

5.8.3.3. ROTATION..................................................................................................................................................... 27

5.8.3.4. SPAN VARIATION .......................................................................................................................................... 27

5.8.4. DEVICE SELECT I O N S F O R I N V E R T E R D U T Y...............................................................................................................................................................28

GENERAL..................................................................................................................................................................... 28

5.8.4.2. THERMAL DIMENSIONING............................................................................................................................. 29

5.8.4.3. SELECTION CRITERIA FOR VERTICAL MOTIONS ........................................................................................... 29

5.8.4.4. SELECTION CRITERIA FOR HORIZONTAL MOTIONS ...................................................................................... 30

5.9 LOAD LIFTING MEANS................................................................................................................................................................ 31

5.9.1. C U R R E N T S U P P L Y...............................................................................................................................................................................................................................31

5.9.2. L O A D H O L D I N G D E V I C E S..............................................................................................................................................................................................................31

5.9.2.1. LIFTING MAGNETS ........................................................................................................................................ 31

5.9.3. G R A B S.............................................................................................................................................................................................................................................................31

5.9.4. LOAD TURNING EQUIPMENT......................................................................................................................................................................................................32

5.10 MAINTENANCE AND CHECKS........................................................................................................................................... 33

5.10.1. M A I N T E N A N C E........................................................................................................................................................................................................................................33

5.10.2. C H E C K S.........................................................................................................................................................................................................................................................33

5.10.2.1. REGULAR CHECKS........................................................................................................................................ 33

5.10.2.2. CHECKS BEFORE COMMISSIONING.............................................................................................................. 34

5.11 AUXILIARY ELECTRICAL EQUIPMENT............................................................................................................................ 34

5.11.1. L IGHTING......................................................................................................................................................................................................................................................34

5.11.1.1. CABIN ........................................................................................................................................................... 34

5.11.1.2. WORKING AREA LIGHTING............................................................................................................................ 34

5.11.1.3. ACCESS AND MACHINERY CABINET LIGHTING.............................................................................................. 34

5.11.1.4. EMERGENCY LIGHTING................................................................................................................................. 34

5.11.2. HEATING AN D A IR-CONDIT IONING .................................................................................................................................................................................35

5.11.2.1. MACHINERY CABINETS............................................................................................................................... 35

5.11.2.2. CABIN ........................................................................................................................................................... 35

5.11.3. AUXILIARY CI RCUIT ............................................................................................................................................................................................................................35

LIST OF SYMBOLS AND NOTATIONS See booklet 1



Booklet 5 - 5/ 35

5.1 FOREWORD

The electrical equipment for hoisting appliances should conform to EN 60204-32 and otherapplicable EN-standards published by CEN and CENELEC. In case the relevant EN-standards do not specify particular requirements, the recommendations given in thisdocument should be followed.

Many details specified in the previous versions of this Booklet 5 are now covered by the EN60204-32.



Booklet 5 - 6/ 35

5.2 POWER SUPPLY

5.2.1. GENERAL

This document deals with a.c. low-voltage systems up to 1000 V.

The power supply system should comply with EN 60204-32 clause 4.3. Voltage variation atthe point of supply (4.3 of EN 60204-32) should not exceed –5% ... +5%. of the rated voltageunder normal operating conditions. In applications with very long cabling distances it may benecessary to limit the voltage variation further. The allowed per cent voltage drop in thedifferent parts of the power supply need to considered case by case. It is recommended thatthe details of the power supply system are agreed between the supplier and the purchasere.g. by using Annex A of EN 60204-32.

The type of the power supply grounding (see IEC 60364-1) may have significant effects onthe requirements of the crane electrification. The type should always be agreed between thepurchaser and supplier. In cases where the power supply type is TN with neutral directlyearthed, equipment will usually perform correctly.

If the power supply type is TN with other than neutral earthing, TT or IT some restrictionsmay need to be considered, e.g. devices designed for neutral earthed TN supply mayincorporate components for EMC filtering, which might

− not withstand the phase to earth voltage of corner earthed systems or IT systemsduring ground fault

− introduce unacceptably high leakage currents to earth.

5.2.2. CUT-OUT AND SAFETY DEVICES

The requirements for crane-supply-switch and crane disconnector are given in clause 5 ofEN60204-32.

Additional requirements may apply, if these devices are used in emergency operations (see9.2.5.4 of EN 60204-32).

5.2.3. CONDUCTOR BARS, CABLE REELS AND FLEXIBLE CABLES

The following clauses in EN 60204-32 set the basic requirements:

− 13.7. Flexible cables

− 13.8. Collector wires, collector bars and slip-ring assemblies

− 14.4.3. Connections to cranes and between moving parts of the crane

According to 13.8.2. of EN 60204-32 the continuity of any protective bonding connection withsliding contacts shall be ensured e.g. by duplication of the current collector.

Additionally, when sliding contacts are used to supply power to electronic drives, doublecollectors should be used also in phase collectors to avoid noise and hardware failures whichmay occur if a contact cuts off momentarily.



Booklet 5 - 7/ 35

5.3 INSTALLATION OF CABLES AND CONDUCTORS

General requirements for cables and wiring practices are given in clauses 13 and 14 of EN60204-32.

5.3.1. CALCULATION OF CROSS-SECTION OF CONDUCTORS

These requirements apply both to the power supply to the crane and also to wiring within thecrane.

The voltage drop must be considered, paying attention to the fluctuation and the voltage dropwithin the power supply. For very long supply lines, not only the resistive but also theinductive part of the supply impedance need to be taken into account.

The cross-section of the conductors should be determined by taking into account themechanical strength required and the electrical load to be carried.

5.3.1.1. CALCULATION OF THE CROSS-SECTION IN RELATION TO THEADMISSIBLE VOLTAGE DROP

When calculating the voltage drop, the most unfavourable position of the hoisting appliancein relation to the supply point must be considered.

When calculating the admissible voltage drop on a supply line used by several hoistingappliances, the start-up (ID) and rated (IN) currents of the motors operating simultaneouslymust be taken into account.

Notes for the calculation:

− In this clause, the rated current (IN) should be considered not necessarily to mean thenameplate current of the motor but the current drawn by the motor at full rated load.

− For squirrel-cage rotor motors ID (start-up current), refer to the manufacturer'scatalogue. In case the motor is controlled by an electronic drive (soft-starter, frequencyconverter etc), the maximum current during any phase of operation should beconsidered as start-up current, although the highest current does not necessarilyoccur when starting the motion. With direct starting the ID is typically 5 to 10 times IN.With electronic drives the start-up current depends on the converter type and on its’adjustments; with frequency converters the ID is typically below 2 times IN.

− For slip-ring rotor motors, consider ID to be approx. 2 * IN.

− For drive with n motors in parallel, apply n * ID or n * IN.

− In case two or more hoisting appliances are working together, they should beconsidered as one appliance by using the sum current ( ID or IN ) of each joint motion.

− In case the power supply also feeds other (continuos) loads such as lighting, hydraulicpumps, lifting magnets or other cranes, the current drawn by these devices need to betaken into account.



Booklet 5 - 8/ 35

For a three phase power supply, the required minimum cross-section (S) of copperconductors can be calculated with the formula:

S = √3 * l * Itot * cos ϕ / ( ∆u * κ ) [mm2], where

l = Effective length of the line [m]

Itot = Sum of the above calculated (ID and IN) currents [A]

∆u = Admissible voltage drop [V]

κ = Electric conductivity [Ω * mm2 * m-1]-1

cos ϕ = Power factor.

5.3.1.2. CALCULATION OF THE MINIMUM CROSS-SECTION IN RELATION TOTHE THERMAL CAPACITY OF THE CONDUCTORS

When calculating the cross-section for the conductor bar, which supplies several hoistingappliances, the actual simultaneous operation of the drive motors must be taken intoaccount.

Notes for the calculation:

− In this clause, the rated current (IN) should be considered not necessarily to mean thenameplate current of the motor but the current drawn by the motor at full rated load.

− In case n>1 motors are driven in parallel, consider : IN = n * IN’ (IN’ = nominal currentfor one motor).

− In case two or more hoisting appliances are working together, they should be handledas one by using the sum current of each joint motion.

− In case the power supply also feeds other (continous) loads such as lighting, hydraulicpumps, lifting magnets or other cranes, the current drawn by these devices need to betaken into account.

The maximum allowed conductor temperature shall not be exceeded during normaloperation. Conductor cross-section should be selected according to manufacturers’specifications or according to IEC60364-5-52.

The tables of IEC 60364-5-52 contain a number of parameters, the most important of whichare:

- conductor type- installation method- correction factors (ambient temperatures, bunching of cables,...); for cable drums see

also EN 60204-32 clause 13.7.3,

The current limits given in IEC 60364-5-52 are for continuous current. If the conductormanufacturer does not provide more detailed guidance for intermittent use consisting of

− “active periods (Ta)” and

− “idle periods (Ti)”,

the information provided in 5.3.1.2.1 or in 5.3.1.2.2 can be used.



Booklet 5 - 9/ 35

5.3.1.2.1. Overloading capacity ofconductors with 10minute cycle time

The allowed increase of the currentdepends on the duration of the loadcycle compared to the thermal timeconstant of the conductor. Table5.3.1.2-a defines the overloadingcapacity ( fED ) of conductors inintermittent duty when duration of theoperating cycle is 10 minutes. These fEDvalues have been calculated using theformulas in 5.3.1.2.2.

5.3.1.2.2. Overloading capacity ofconductors with anycycle time

If the duration of the operating cycle isvery short compared with the timeconstant of the cable (T) it may bepossible to apply higher factors thanshown in 5.3.1.2.1.

The allowed overloading factor fED forthe particular duty cycle can beexpressed as a function of Ta, Ti, and Tas shown below.

The thermal time constant T to be used in the fED calculation is given in Table 5.3.1.2-b.

5.3.2. INSTALLATION CONDITIONS

Type of protection for connection and distribution equipment must be suitable for surroundingconditions following the guidelines given in EN 60204-32 clause 12.3.

The connections and linking terminals should be placed in cabinets or boxes. Plug-inarrangements whose accidental connection could be dangerous should be clearly separatedunless their design precludes this risk. In order to ensure continual mechanical protection, theprotective covering of the cables and conductors should enter housings through packingglands or such similar devices.

The wires or conductors belonging to electrical circuits with different rated voltages may bearranged within a single enclosure or may form part of the same cable provided that thesewires or conductors are insulated against the highest rated voltage.

Conductors having single insulation can only be installed in conduits or trunking whose endsare fitted with adequate protection.

Non-sheathed conductors and cables, which are fixed to parts of the framework should beprotected, if necessary, against any mechanical wear and tear.

Table 5. 3.1.2-B

mm2 1,5 2,5 4 6 10 16 25 35

T/min 2,7 3,1 3,6 4,2 5,2 6,4 7,9 9,4

mm2 50 70 95 120 150 185 240 300

T/min 11,3 13,6 16,1 18,4 21,0 23,7 27,7 31,8

−

+

−

=

TTa

TTiTa

ED

e-1

e -1 f

Table 5. 3.1.2-A

crosssection

fED for a 10 minute cycle

Ta / (Ta + Ti)

mm2 0,6 0,4 0,25 0,15

1,5 1,044 1,120 1,265 1,505

2,5 1,058 1,150 1,315 1,580

4 1,075 1,183 1,369 1,660

6 1,092 1,215 1,421 1,737

10 1,116 1,260 1,493 1,842

16 1,139 1,303 1,561 1,942

25 1,161 1,344 1,626 2,037

35 1,177 1,373 1,673 2,105

50 1,193 1,403 1,719 2,173

70 1,207 1,429 1,760 2,231

95 1,219 1,450 1,793 2,280

120 1,227 1,464 1,816 2,314

150 1,234 1,477 1,836 2,343

185 1,240 1,488 1,854 2,369

240 1,247 1,501 1,874 2,397

300 1,252 1,510 1,888 2,419



Booklet 5 - 10/ 35

5.4 ELECTRICAL PROTECTIVE AND SAFETY EQUIPMENT

5.4.1. SAFEGUARDING MOTORS AGAINST OVERHEATING

Motor overload protection shall fullfill the requirements of 7.3 of EN 60204-32.

Normal thermal relays or protection methods based on calculating methods may not performproperly in short time duty (S2 of IEC 60034-1) and in intermittent duty, (S3...S8 of IEC60034-1) because e.g.− their time constant may not be comparable to that of the load cycle− initial temperature during power up is not known− when self-ventilated motors are operated at low speeds the cooling is not efficient

Therefore protection methods based on actual temperature measurement of the motor arepreferred.

The overload protection can also be implemented by electronic devices, which may be eitherseparate devices or integrated in the control or drive unit.

5.4.2. SAFEGUARDING WIRING

The cross-section of a conductor should be determined according to the current intensity towhich it is subject during both normal running of the motor and starting-up or electricalbraking, see clause 5.3.2.

Whether the loads (motors) are overloadprotected or not, all wires should be safeguardedaccording to 7.2 of EN 60204-32 against any overcurrent, which could result from a short-circuit or faulty insulation.

The protective device shall be rated for the anticipated short-circuit currents.

5.4.3. SAFEGUARDING AGAINST ABSENCE OR INVERSION OF PHASES

Where an incorrect phase sequence of the supply voltage can cause a hazardous conditionor damage to the hoisting machine, protection should be provided according to 7.8 of EN60204-32.

If the absence of phases may occasion a danger, the appropriate safety measures must betaken.

5.4.4. ACTION OF SAFETY DEVICES

When several motors drive the same motion, the action of a safety device should stop all ofthe motors for this movement.

After a safety device has been activated, it should be possible for the equipment to be startedup again only manually.



Booklet 5 - 11/ 35

5.4.5. PROTECTION AGAINST THE EFFECTS OF LIGHTNING

For very tall pieces of hoisting equipment which are erected in particularly exposed locations,the effects of lightning must be considered

− on pieces of vulnerable structure (for example : jib support cable)

− on anti-friction bearings or runners which form a link between large parts of the frame (forexample : slewing ring, travel runner).

When necessary, safeguarding against the effects of lightning should be carried out e.g. byfollowing IEC 61024-1.

For the safety of personnel, it is recommended that the runner rails for the lifting equipmentare earthed.



Booklet 5 - 12/ 35

5.5 LIMITING AND INDICATING DEVICES

In addition to the requirements given later in this clause, the limiting and indicating devicesshould comply

− with 7.7 of FEM 1.001 Booklet 7, and

− with EN 12077-2, and

− with the EN-standards for the particular crane type, and

− in case there is no published EN-standards for the the particular crane type, therequirements given in ISO 10245 for the particular crane type should be followed.

5.5.1. GENERAL REQUIREMENTS

A limit switch should bring about the arrest of motion by opening the electric circuit andkeeping it open as long as safety conditions are not restored.

If it is unavoidable to by-pass a safety device, this operation should only be able to beeffected with the aid of a device which, when no longer actuated, automatically re-inserts thesafety device. The provisions of 9.2.4 of EN 60204-32 should be followed, and if necessary apermanent warning signal should be given.

In general, the safety functions should comply with safety category 1 if hardwired or safetycategory 2 of EN 954-1 if not hardwired.

5.5.2. MOTOR OVERSPEED PROTECTION

All electronically controlled hoisting motions shall be equipped with overspeed protection.The overspeed protection shall prevent− uncontrolled and unintentional motions and− all parts of the mechanism from reaching its mechanical limit speed.

The trigger limit of the overspeed protection shall be set so that the mechanical brake iscapable to stop the motion safely in all conditions. In general, the trigger limit should notexceed 1,2 times the specified speed at nominal load. When utilising field weakening with areduced load, the trigger limit can be adjusted to a higher value, in general not exceeding 1,2times the specified speed for that load.

The emergency stopping with any possible speed and load combination shall not cause anyhazard including the cases where the drive is intended to operate above the nominal speed.

NOTE : Topics to be considered include allowed speed/load combinations, time delays in thesystem (particularly brake delays), mechanical speed limit of the machinery, reliabilityof load measurement/estimation.



Booklet 5 - 13/ 35

5.6 CONTROLS

5.6.1. COMPONENTS

5.6.1.1. RELAYS AND CONTACTORS

Relays and contactors must comply with the requirements of EN6024-32 clause 4.2.2.

In case the crane will be used at an altitude in excess of 1000 m, this shall be considered byselecting the contactors and relays.

Reversing contactors should be of the electrically or mechanically interlocking type.

5.6.1.2. RESISTOR UNITS

5.6.1.2.1. General

Resistor units should be accommodated in suitable enclosures according to EN 60204-32 cl.12.3.

The temperature limit of the resistance material is defined in 7.2.2.8 of IEC 60947-1.Temperature rise of the touchable surfaces of the resistor enclosures shall comply with7.2.2.2 of IEC 60947-1. When designing the resistor units, the equivalent torque, cyclicduration factor and switching rate have to be considered.

Cooling fans for resistors should be used only if proper monitoring is arranged (air flowdetection and/or temperature measurement). In dirty environments fans should not be usedto ensure reliability.

5.6.1.2.2. Braking resistors for inverter drives

The braking resistor of a hoisting drive shall be capable of absorbing the generative energywhen lowering the maximum load at maximum speed. For horizontal motions, the brakingresistor shall be capable of absorbing the generative energy during deceleration of themotion also taking into account the possibility of a swinging load and the wind push (the loadand load attachment included).

The braking resistor shall be thermally capable to absorb the generative energy duringsuccessive drive cycles of the application. The failure of the braking resistor shall neither leadto the loss of stopping capability nor to any uncontrolled acceleration of the motion.

The braking resistors and their enclosure may heat up to hazardous temperatures. Protectionor warning of the hazard shall be provided depending on the application. The requirements ofclause 5.1.4.1 of prEN 13135-2 shall be fulfilled.

NOTE : The braking resistor may also be common for several hoist and travel drives. In suchcases the dimensioning of the braking resistor shall be made accordingly.

NOTE : The braking resistor is usually connected to the DC-bus of the inverter and due tothis it becomes live always when electric power is supplied to the inverter – also during notrunning the motor.



Booklet 5 - 14/ 35

5.6.2. CONTROLGEAR, LOCATION, MOUNTING AND ENCLOSURES

Switching devices, controlgear and panels housing electrical equipment may be enclosed:

− in cabinets or housings,

− in special enclosed spaces,

− in the supporting structure (principally the crane girder) of the hoisting appliance.

These enclosures and the equipment installed should comply with cl. 12 of EN 60204-32.

5.6.3. TYPE OF CONTROL

5.6.3.1. ENERGISATION

The lifting appliance can only be energised when all the control devices are in the offposition. This off position can be determined either by a checking circuit or by using hold-to-run controls. As required in EN 60204-32 clause 10.7.1, a device for emergency stop or foremergency switching off shall be located at each operator control station.

5.6.3.2. CAB CONTROL

The controls should be so arranged that the operator has an adequate view of the crane’sworking area.

The control for hoisting appliances should preferably be arranged on the right-hand side ofthe operator’s seat.

5.6.3.3. FLOOR CONTROL

Push-buttons or other switching devices, which automatically return to their “off” position assoon as they are released, should be provided for the control of all motions by pendantcontrol units.

Housings of pendant control units should preferably be of fully insulating material or ofmaterial with protective insulaion. Metal parts accessible from the outside, which passthrough the insulation, should be separately earthed.

The surface of the housing must be a vivid colour. For indoor operation, the degree ofprotection should be at least IP43, and for outdoor operation at least IP55

Pendant control units should be suspended with a strain relief arrangement.

5.6.3.4. CABLE-LESS CONTROLS

The requirements of 9.2.7 of EN 60204-32 and Annex C of prEN 13557 apply to cable-lesscontrols incl. radio and infrared controls.

The transmitter must have a minimum protection class IP 43 for indoor use and IP 55 foroutdoor use.



Booklet 5 - 15/ 35

5.6.4. CONTROL OF MECHANICAL BRAKES

The requirements of EN 60204-32 clauses 9.3.4, 15.6, and 15.7 should be fulfilled.

Measures should be taken to ensure that no unintentional movements occur when starting.

5.6.4.1. SECOND BRAKE

Cranes, which require particular safety, e.g. in steel works or with dangerous or melted loads,should be provided with a second brake.

The operation of the second brake shall be arranged according to the design of the drive. It isrecommended that under normal operating conditions, the second brake is always be appliedon stopping, after the motion has been brought to a halt by the main brake. In someapplications – for example if waiting for the releasing of the second brake would causeunacceptable time delay at each starting - it may be necessary to apply the second brakeonly when the crane switch (main contactor) is de-energized.

In the event of an emergency stop, the second brake should be applied immediately.



Booklet 5 - 16/ 35

5.7 ENVIRONMENT

The electrical equipment shall be suitable for use in the physical environment and operatingconditions specified in 4.4.2 to 4.4.8 of EN 60204-32. When the physical environment or theoperating conditions are outside those specified, an agreement may be needed between thesupplier and the user (see annex A of EN 60204-32).

5.7.1. POTENTIALLY EXPLOSIVE ENVIRONMENTS

In potentially explosive atmospheres, the electrical equipment including motors shall complywith relevant additional requirements (e.g. EN 50014...50020).

5.7.2. ELECTROMAGNETIC COMPATIBILITY

The requirements of 4.4.2 of EN 60204-32 apply.

The manufacturer should perform an EMC analysis to define what essential safety and/orprotection requirements apply to his apparatus and how to conform to them. Themanufacturer should apply− harmonised specific product family standards and− harmonised generic standards for the residential, commercial, and light industrial

environment, and industrial environmentto bring the hoisting machine into compliance with the EMC Directive.

When using only CE marked apparatus and components (complying with the EMCDirective) and following strictly the instructions and limitations of use of the manufacturer ofthese products, the finished hoisting machine could be considered to comply with the EMCDirective and no further verification is then needed. The manufacturer shall provide clearinstructions for assembly/installation/operation/maintenance in the instructions for use toensure that the compliance with the Directive can be reached in all expected electromagneticenvironments.

In cases where the manufacturer does not restrict himself to only using CE markedapparatus, a thorough EMC analysis and verification of compliance is needed.



Booklet 5 - 17/ 35

5.8 SELECTION OF MOTORS

5.8.1. CRITERIA FOR MOTOR SELECTION (IEC 60034-1)

When selecting motors for an application, at least the following details need to be considered:

- required powers-the thermal power is also included in these required powers,

- maximum rated torque and maximum acceleration torque,

- cyclic duration factor,

- number of cycles/hour,

- type of control (type of braking),

- speed regulation,

- type of power feed,

- degree of protection, (environment conditions),

- ambient temperature,

- altitude.

The motor has to comply with the following two dimensioning requirements:

- the thermal calculation according to clause 5.8.1.3.

- the required maximum torque:

• for hoisting mechanisms according to clause 5.8.2.1.

• for horizontal motions according to clause 5.8.3.1.

NOTE: Additional or different criteria may be needed depending on the driving system.

NOTE: Selection of motors for inverter drives is defined in clause 5.8.4, which also covers thedimensioning of inverter drives.

If the required torque diagrams, in order to define the mean equivalent torque (cl. 5.8.1.3.1.)are not available, these can be assessed respectively with the help of tables T 5.8.2.2a. andT 5.8.3.2a

5.8.1.1. REMARKS ON THE SELECTION OF MOTORS

The selection of the motor should be agreed with the manufacturer in taking into account thetorque and powers calculated in the following clauses and the real operating conditions of themotor.

In the event of electronic power control, the definition of the motors has to be made incooperation with the manufacturer, taking into account the cooling system and the speedrange.

In cases where two or more mechanisms drive the same motion, the following shall beconsidered:

− both static and dynamic synchronisation of the motions according to the needs of theapplication

− necessary interlocks between the mechanisms to ensure safe operation

− both static and transitional asymmetrical loading of the mechanisms and consequentlyneeded adequate dimensioning of motors and other drive components



Booklet 5 - 18/ 35

5.8.1.2. DEGREE OF PROTECTION (IEC 60034-5)

The degree of protection for all motors shall be according to EN 60204-32 clause 15.2. Incase of water condensation risk, care should be taken that the water condensation drainholes remain open.

5.8.1.3. THERMAL CALCULATION OF THE MOTOR

5.8.1.3.1. Mean equivalent torque

In order to carry out the thermal calculation, the mean equivalent torque must be determinedas a function of the required torque during the working cycles, by the formula:

n21

n2

n22

212

1med t ... t t

t * M ... t * M t * MM

++++++=

Where :

t1, t2, ...,tn are the durations of the time periods during which the different torquevalues are produced; periods of rest are not taken into account.

M1, M2, .... Mn are the calculated torque values taking into account all the inertiaforces including the one of the rotor mass of the motor.

In case of variable loads at least 10 successive working cycles must be taken into account(see definition 2.1.2.2.).

Diagram 5.8.1.3.1. shows an example of the torque for 2 different operating cycles.

5.8.1.3.2. Mean equivalent power

Starting from the mean equivalent torque, the mean equivalent power Pmed [kW] is defined bythe formula:

Pmed = (Mmed * nm / 9 550 )

where:

Mmed = mean equivalent torque [Nm]

nm = speed of motor [1/min]

If the motor is rated for S3-duty and the rating corresponds to the actual use in the particularapplication, then the motor can be selected according to the calculated mean equivalentpower.

For S1-rated squirrel cage motors, the thermal dimensioning shall be carried out according tothe method described in clause 5.8.1.4. (NOTE: applies only for direct starting motors).

For the motor selection, the mean equivalent power P med should be corrected as a function ofaltitude if it exceeds 1000 m and the ambient temperature if it deviates from 40 °C (See5.8.1.5.).



Booklet 5 - 19/ 35

Torque

raisingwith load

loweringwith load

raisingwithout load

loweringwithout load

time

without loadwith driving wind

with loadand resisting wind

hoistingmotion

horizontalmotion

CYCLE 1

CYCLE 2

raising withpartial load

lowering withpartial load

raisingwithout load

loweringwithout load

time

with partial loadand resisting wind

without loadwith driving wind

hoistingmotion

horizontalmotion

t1 t2 t3 t4 t5 t6

t7

t8 t9 t10

t11 t12

M1

M2

M3 M4

M5

M7

M8

M9 M10

M11

M12

tr2tr1 tr3 tr4

tr1 tr2 tr3

M1

M2

M3 M4

M5

M6

t1 t2 t3 t4 t5 t6

t1 t2 t3 t4 t5 t6

t7

t8 t9 t10

t11 t12

M2

M3 M4

M5

M8

M9 M10

M11

tr2tr1 tr3 tr4

M1

M1

tr1

M2

M3 M4

M5

M6

t1 t2 t3

tr2

t4 t5 t6

tr3

M6

M6

M12

Diagram 5.8.1.3.1.

Typical torques for 2 different operating cycles:

Hoisting motion Horizontal motiontr: rest time tr: rest timeM1,M4,M7,M10, starting torque M1,M4 starting torqueM2,M8, hoisting torque raising M2 working torque with windM3,M6,M9,M12 braking torque M3, M6 braking torqueM5,M11, hoisting torque lowering M5 torque without load with wind



Booklet 5 - 20/ 35

5.8.1.4. SQUIRREL CAGE MOTORS WITH DIRECT STARTING

The following inequality has to be fulfilled for the thermal dimensioning of squirrel cagemotors:

Ck ( 1 - ηN ) * PN * T > ( 1 - ηmcy ) * Pmcy * tN + ( PN * tE * ID / IN ) - ( J * nmcy2 * 10-3 / 182 )

NOTE: Subscript “cy” refers to cycle.

( 1 - ηN ) * PN * T loss energy of the motor working at its ratedpower (S1) during a time T

( 1 - ηmcy ) * Pmcy * tNloss energy of the motor during the time tN

(constant speed) in a cycle( PN * tE * ID / IN ) - ( J * nmcy

2 * 10-3 /182 )

loss energy of the motor during the startingand braking phases

Ck correction factor linked to the type of motor

PNnominal power [kW] of the motor incontinuous (S1) duty

ηN efficiency of the motor at PN

Pmcy. Mmcy * nmcy / 9 550 [kW]nmcy speed of motor [1/min] for power Pmcy

Mmcy

mean resisting torque [Nm] calculated in thesame manner as Mmed (see clause 5.8.1.3.1),but not including the starting and brakingphases.

ηmcy efficiency of the motor at power Pmcy

Ttotal time of cycle [s],= tN + tE + tr

EDcyclic duration factor (see clause 5.8.1.6.)= 100 * ( tN + tE ) / T

tNoperating time [s] at constant speed duringone cycle.

tE

equivalent time [s] of starting and brakingduring one cycle,= ( π / 30 ) * nmcy * J / Macc / ( dccy + 0,5 * d icy +3 * fcy )

tr total rest (idle) time [s] during one cycle.

J total inertia of masses in motion referred tothe motor shaft [kgm2].

dccythe number of complete starts during onecycle

dicy the number of impulses during one cycle

fcythe number of electrical brakings during onecycle

Maccthe mean accelerating torque [Nm],= MDmcy - Mmcy

MDmcy mean starting torque of motor [Nm]



Booklet 5 - 21/ 35

The following data has to be indicated by the motor manufacturer:

PNnominal power [kW] of motor in continuous(S1) duty

η1/4 ... 5/4 efficiency for 1/4 PN ... 5/4 P N powersJM moment of inertia of motor [kgm2]

n1/4 ... 5/4 speed of motor at 1/4 PN ... 5/4 PN [1/min]MDmcy mean starting torque of motor in [Nm]

ID/INratio between the starting current and thecurrent at PN

Ck correction factor linked to the type of motor

In case the Ck factor is not mentioned in the manufacturer's catalogue, Ck shall be takenequal to 1 for motors of polarity equal or above 4.

5.8.1.5. POWER CORRECTION IN FUNCTION OF AMBIENT TEMPERATURE ANDALTITUDE

These corrections are depending from the type of motor, the cooling method and theinsulation class.

The precise calculation can only be made by the motor manufacturer in supplying them withthe following indications:

- Pmed without correction

- value of ambient temperature

- altitude

The thermal dimensioning can be based on the formulas below and on the values of kindicated in Diagram 5.8.1.5:

P’med = Pmed / k

or

P'mcy = Pmcy / k (for squirrel cage motors)

P'mcy or P'med = required nominal power of motor as function of altitude and ambienttemperature.



Booklet 5 - 22/ 35

ALTITUDE

Ambient Temperature

Diagram 5.8.1.5 = Correction factor k as function of ambient temperature and altitude

Note 1: The k > 1 coefficient values are to be applied only by agreement between the motormanufacturer and the hoisting appliances manufacturer.

Note 2: The ambient temperature shall be indicated above an altitude of 1000 m.

5.8.1.6. CYCLIC DURATION FACTOR AND NUMBER OF WORKING CYCLES PERHOUR

The cyclic duration factor is given by the following formula:

ED = Operating time / (Operating time + idle time ) * 100 (%)

The operating time and the number of operations per hour of the motors as well as thenumber of working cycles of the crane, are an important base for the thermal definition of themotors and which should be agreed between the user and the manufacturer of the crane. Incase it is not possible to give these indications in a precise manner, it should be referred totables T 5.8.2.2 a and T 5.8.3.2 a.



Booklet 5 - 23/ 35

5.8.2. MOTORS FOR VERTICAL MOTIONS

5.8.2.1. DETERMINATION OF REQUIRED TORQUE

For a hoisting motor, the required power to raise the maximum nominal load (P Nmax) isdefined in kW in taking account of the configuration of the transmission and of the reevingaccording to the following formula:

PNmax = L * VL * 10-3 * η

Where:

L = maximum nominal permissible lifting force [N]

VL = lifting speed [m/s]

η = efficiency of machinery

The required torque to raise the maximum nominal load is:

MNmax = PNmax * 9 550 / n, where

nm = rotating speed of the motor [1/min].

In order to be able to develop the necessary torque for acceleration, for lifting the test load orfor compensating for variations in the mains voltage and frequency, the torque developed bythe motor must satisfy the following minimum condition:

- For squirrel cage motors with direct starting:

Mmin / MNmax ≥ 1,6, where

Mmin is the minimum torque of the motor during starting.

- For slip ring motors:

Mmax / MNmax ≥ 1,9

with Mmax being the maximum torque of the motor.

- For all types of motors which are fed by voltages and /or variable frequencies:

Mmax / MNmax ≥ 1,4

The mechanical braking torque at the motor shaft (MF) should at least be equal to:

- Static MF ≥ 2 * MNmax * η2

- Dynamic MF ≥ 1,6 * MNmax * η2

Definition of the braking torque:

- Static: is the required minimum torque to prevent the SWL (safe working load) rotating themachinery.

- Dynamic: is the braking torque produced by the brake during the whole duration of abraking cycle.

In case electrical braking is applied, it shall be capable to slow down the load in completesafety.



Booklet 5 - 24/ 35

5.8.2.2. CYCLIC DURATION FACTOR AND NUMBER OF CYCLES PER HOUR

In the case where no precise indications are given, the values mentioned in Table T 5.8.2.2.acan be chosen.

Table T.5.8.2.2.a.

Indications for the number of cycles per hour and the cyclic duration factor for the verticalmotions

Type of appliance Particulars Number

Type of mechanism ED%

Refe-rence Designation

concerningnature of use

(1)

ofcycles

perhour

LiftingDerricking hinged

boom

Derricking

boom

1 Hand-operated (=notmotorised) appliances

2 Erection cranes 2-25 25-403 Erection and dismantling

cranes for power stations,machine shops, etc.

2-15 15-40

4 Stocking and reclaimingtransporters

Hook duty 20-60 40 S2 (2)15-30min


Grab ormagnet

25-80 60-100 S2 (2)15-30min

6 Workshop cranes 10-50 25-407 Overhead travelling cranes,

pigbreaking cranesScrapyard cranes

Grab ormagnet

40-120 40-100

608 Ladle cranes 3-10 40-609 Soaking-pit cranes 30-60 40-6010 Stripper cranes, open-hearth

furnace-charging cranes3010

6060

11 Forge cranes 6 4012-a

12-b

Bridge cranes for unloading,bridge cranes for containersOther bridge cranes (with craband/or slewing jib crane)

a – Hook orspreader duty

b – Hook duty

20-60

20-60

40-60

40-60

S2 (2)15-30min

S2 (2)15-30min

13 Bridge cranes for unloading,bridge cranes (with crab and/orslewing jib crane)

Grab ormagnet

20-80 40-100

60

S2 (2)15-30min

14 Drydock cranes, shipyard jibcranes, jib cranes fordismantling

Hook duty 20-50 40 40



Booklet 5 - 25/ 35

15 Dockside cranes (slewing, ongantry, etc.), floating cranesand pontoon derricks

Hook duty 40

20

60

40

40-60


Grab ormagnet

25-60 60-100 40-60

17 Floating cranes and pontoonderricks for very heavy loads(usually greater than 100 t)

2-10 S1 (2)or S230 min

S2 (2)15-30min

18 Deck cranes Hook duty 30-60 40 4019 Deck cranes Grab or

magnet30-80 60 60

20 Tower cranes 20 40-60 25-4021 Derricks 10 S1 (2)

or S230 min

S1 orS2 (2)30 min

22 Railway cranes allowed to runin train

10 40

1) This column comprises only some indicatory typical cases of utilisation

2) it is recommended for S1 and S2 to refer to the definition IEC 60034-1

5.8.3. MOTORS FOR HORIZONTAL MOTIONS

In order to select travel motors correctly, all the necessary torque (or power) values must beconsidered, taking into account the starting time, the number of starting cycles per hour andthe cyclic duration factor. The maximum transmissible torque of the travel motors is limited bythe adhesion of the driven travel wheels on their tracks.

5.8.3.1. DETERMINING THE NECESSARY TORQUE

- Speed maintaining torque

To determine the torque necessary for maintaining the speed, account has to be takenof the sum of forces (w) resisting to travel resulting from the dead-weight, the load andoperating conditions such as:- deformation of the running surface,- friction of the wheels on straight sections and in curves,- wind force,- gradients in the track,- necessary traction of power supply cable.

- Acceleration torque (running up to speed)

The acceleration torque shall take into account the sum of the acceleration forces ofthe mass of lifted load and of the other masses put into motion. The recommendedacceleration values are given in Table T 2.2.3.1.1 (booklet 2).



Booklet 5 - 26/ 35

The travel motors must deliver the necessary torque in the following operating conditions:

- Case I for cranes not exposed to wind

- Case II for cranes exposed to wind

The necessary torque can be calculated by the following formulae (see diagram5.8.1.3.1)

Case I

M1, ... Mn = [ a * ( m + mL ) + w0 ]* v * 60 / ( 2 * π * nm * η )

Case II

The largest of the values from the results of the following formula shall be taken intoaccount:

M1, ... Mn = [ a * ( m + mL ) + w8 ]* v * 60 / ( 2 * π * nm * η )

and

M1, ... Mn = w25 * v * 60 / ( 2 * π * nm * η )

where:a acceleration [m/s2] (at constant speed a = 0)m = m0 + mrot * η , equivalent mass [kg] of all parts put into motion,

excluding the load, which is supposed to be concentrated at thesuspension point of the load.

mL mass of lifted load [kg]m0 mass [kg] of the whole of the elements, excluding the load,

undergoing the same horizontal motion as the suspension point ofthe load.

mrot = Σ( J * nχ2 / v2 ) / 91,2 , equivalent mass [kg] of the inertia ofrotating parts reduced to linear motion, where:

nχ speed of rotating masses [1/min]

J moment of inertia of all rotating masses [kgm2]w0, w8, w25 total travel resistance [N] (w can also become negative in

some cases)w0 at zero windw8 at a wind of 80 N/m2

w25 at a wind of 250 N/m2

v travel speed [m/s]nm rotation speed of motors [1/min]η overall efficiency of mechanism

The motor shall be selected based on the highest of the calculated torque values (M1, ... Mn)in case I and II.

For slip ring motors used for the horizontal motions, the starting resistances shall be sodefined that the minimum torque delivered by the motor is never less than 1,2 times thetorque required to maintain the travel speed.



Booklet 5 - 27/ 35

5.8.3.2. CYCLIC DURATION FACTOR AND NUMBER OF CYCLES PER HOUR

In the case where no precise indications are given, the values mentioned in Table T5.8.3.2.a. can be chosen.

5.8.3.3. ROTATION

The calculation is carried out in an analogous fashion to clause 5.8.3.1, angular speeds beingsubstituted for the linear speeds.

5.8.3.4. SPAN VARIATION

If the span variation in the case of luffing jibs, leads to an elevation or to a lowering of thecentre of gravity of the masses put into motion, the calculation can be carried out in ananalogous fashion to clause 5.8.3 in inserting into the factor (w) the forces required to thevertical displacement of the centre of gravity.

Table T. 5.8.3.2.a

Indications for the number of cycles per hour and the cyclic duration factor for the horizontalmotions

Type of appliance Particulars Number

Type of mechanism ED%

Refe-rence Designation

concerningnature of use

(1)

ofcycles

perhour

Rotation

Crab Travel

1 Hand-operated appliances2 Erection cranes 2-25 25 25-40 25-403 Erection and dismantling

cranes for power stations,machine shops, etc.

2-15 25 25


Hook duty 20-60 15-40 40-60 25-40


Grab ormagnet

25-60 40 60 15-40

6 Workshop cranes 10-50 25-40 25-407 Overhead travelling cranes,

pigbreaking cranes, scrapyardcranes

Grab ormagnet

40-120 40-60 60-100

8 Ladle cranes 3-10 40-60 40-609 Soaking-pit cranes 30-60 40 40-60 40-6010 Stripper cranes, open-hearth

furnace-charging cranes3010

4040

6040

11 Forge cranes 6 100 25 2512-a

12-b

Bridge cranes for unloading,bridge cranes for containersOther bridge cranes (with craband/or slewing jib crane)

a – Hook orspreader duty

b – Hook duty

20-60

20-60

15-40

25-40

40-60

40-60

15-40

25-40



Booklet 5 - 28/ 35

13 Bridge cranes for unloading,bridge cranes (with crab and/orslewing jib crane)

Grab ormagnet

20-80 40 40-100 15-60

14 Drydock cranes, shipyard jibcranes, jib cranes fordismantling

Hook duty 20-50 25 40 25-40


Hook duty 40

2025-40 40 15-25


Grab ormagnet

25-60 40-60 25-40

17 Floating cranes and pontoonderricks for very heavy loads(usually greater than 100 t)

2-10 15-40

18 Deck cranes Hook duty 30-60 4019 Deck cranes Grab or

magnet30-80 60

20 Tower cranes 20 40-60 25 15-4021 Derricks 10 2522 Railway cranes allowed to run

in train10 25

1) This column comprises only some indicatory typical cases of utilisation

5.8.4. DEVICE SELECTIONS FOR INVERTER DUTY

5.8.4.1. GENERAL

When feeding asynchronous motor by inverters,the motor speed is always close to the no-loadpoint (= between the maximum torque point andzero-torque point) on the torque curves shown inthe figure 5.8.4.1. The speed adjustment asrealized by changing the supply frequency to themotor. In the field-weakening region above thenominal motor speed nN, the motor’s maximumtorque (“pull-out torque” Mpo) decreases inverselyproportional to the square of the speed, whichsets limitations to the use of field-weakening.

The figure also shows the motor current at ratedspeed (thick line), which increases very rapidly ifthe motor is loaded excessively.

NOTE 1: If the motor is loaded up to the pull-out torque or too close to it, there is ahigh risk of getting into an unstablesituation. The required minimum torquemargins are defined in 5.8.4.3 and 5.8.4.4. An even higher margin may be neededdepending on

Figure 5.8.3.4

0

1

2

3

4

5

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6

NI

I

NM

M

Nn

n



Booklet 5 - 29/ 35

• the characteristic of the inverter (e.g. vector control or U/f control, with or withoutspeed feedback), and

• the foreseen environment (e.g. variation of supply voltage, load swaying, transientphenomena).

NOTE 2: The curves shown in the figure are indicative only, and actual values for aparticular motor type need to be asked from the motor supplier.

NOTE 3: The advice given in 5.8.1.1 shall be followed throughout this clause.

5.8.4.1.1. Use of field weakening

As with field weakening the motor's pull-out torque decreases, only a limited load can behandled. The allowed maximum percent load for different speeds can not be specified assuch, but must be analyzed in more detail. The main points affecting are the load to behandled and the rotational inertia of the system (motors, brakes, couplings, gears) togetherwith the desired acceleration rate.

When applying field weakening is considered, all restrictions caused by the mechanicalcomponents (motor, brake, gear) have to be checked. Note also that increasing the speedincreases the stopping distance in quadrature.

5.8.4.2. THERMAL DIMENSIONING

The thermal calculation of the motor can be done as shown in 5.8.1.3. When using S1-ratedmotors, instead of the inequality of 5.8.1.4, the below formula shall be used.

Ck (1 - ηN ) * PN * T > ( 1 - ηmed ) * Pmed * (T - tr )

The operational class of the crane as well as the load spectrum has only a negligible effecton the inverter selection. The following items may vary depending on application and shouldbe checked:

• dimensioning of the braking resistor

• need of enclosure cooling.

5.8.4.3. SELECTION CRITERIA FOR VERTICAL MOTIONS

5.8.4.3.1. Motor selection

The required torque (MNmax) to raise the maximum nominal load is calculated as in 5.8.2.1.The torque Mmax developed by the motor shall comply with 5.8.2.1.

In order to be able to develop the necessary torque for acceleration, for lifting the test load orfor compensating for variations in the mains voltage, the largest of the torques M1... Mn (=Mi,max) during the load cycle (see 5.8.1.3.1) should comply with

Mpo / Mi,max ≥ 1,3,

unless it is ensured by the control system that exceeding the pull out torque Mpo can beavoided. See also NOTE 1 in 5.8.4.1.

NOTE: In the field weakening region, a lower safety margin according to the invertermanufacturer’s instructions may be appropriate.



Booklet 5 - 30/ 35

5.8.4.3.2. Inverter selection

The continuous current rating of the inverter shall be at least equal to the motor current atload torque MNmax. The current required by the motor at any foreseen loading includingdynamic situations shall not exceed the short time overload rating of the inverter.

5.8.4.4. SELECTION CRITERIA FOR HORIZONTAL MOTIONS

5.8.4.4.1. Motor selection

The required torques (M1 ... Mn) are calculated as in 5.8.3.1. The largest of them (M i,max) mustsatisfy the following minimum condition:

Mpo / Mi,max ≥ 1,2,

unless it is ensured by the control system that exceeding the pull out torque Mpo can beavoided.

The possibility to apply field weakening should be checked case by case. Usually there arevery limited possibilities to apply field weakening in horizontal motions due to the fact thatvery often a major portion of the torque requirement comes from the acceleration (anddeceleration) dependent term. Typical applications for field weakening are cranes exposed towind during low wind condition.

5.8.4.4.2. Inverter selection

The continuous current rating of the inverter shall be at least equal to the motor current at thehighest speed maintaining torque. The current required by the motor at any foreseen loadingincluding dynamic situations shall not exceed the short time overload rating of the inverter.



Booklet 5 - 31/ 35

5.9 LOAD LIFTING MEANS

5.9.1. CURRENT SUPPLY

In view of the arduous duty to which current supply systems are subjected, the electricalequipment must be selected and installed with special care.

Supply cables should be able to be wound on cable winders and their mechanical strength,resistance to external influences and heat-resistance, must be suitable for the serviceconditions.

Cable fixing means should be so selected that all strain on the connections or damage to thecables is avoided.

Cables should be installed and guided in such a way as to exclude the possibility of damagein normal service.

5.9.2. LOAD HOLDING DEVICES

The requirements given in this clause apply to all load holding devices such as liftingmagnets and vacuum lifters.

Load holding devices are normally designed for a cyclic duration factor of 50 %. Other cyclicduration factors should be agreed between the manufacturer and user.

The tear-off force should be at least twice the lifting capacity.

If there is a stand-by power supply from batteries, the holding time should be at least 20minutes. In this case, an automatic charging unit and a charge level indicator should beprovided. Use of the stand-by supply should be indicated visually and audibly for generalwarning. If the battery voltage level is not adequate, a device preventing the installation frombeing used should come into effect.

5.9.2.1. LIFTING MAGNETS

The insulation class of the windings should be selected according to the power loss, theambient temperature and, if necessary, the heating caused by the goods handled.

The lifting capacity for a lifting magnet should be specified for a precise load at rated voltageand operating temperature of the magnet coil.

5.9.3. GRABS

The drive motors (electro-hydraulic or electro-mechanical drive) should be designed for S3,S4 or S6 duty depending on type and application.

In normal service, the motors and electrical equipment located on the grab must comply withIP 55 at least. For underwater operation the degree of protection must be IP 57 at least. Dueto the special service conditions of this equipment, jolts and vibrations must be givenparticular attention.



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5.9.4. LOAD TURNING EQUIPMENT

Load turning equipment should be so designed that loads can be accelerated and brakedwithout the ropes twisting. The arrangement of the lifting ropes, the load, the lifting height, thecentre of gravity and the moment of inertia of the load and loading beam if applicable shouldbe taken into account in the design of the equipment.

The installation of guides such as telescoping or articulated systems may be used in order toprevent the twisting of ropes.

All electrical connections to turning parts should be designed in accordance with the turningrange.

If the turning motor is mounted on the supporting structure of the hoisting appliance, it mustcomply with the degree of protection of the other motors on the structure at least. If theturning motor is mounted on the load lifting means, it must comply with IP 44 at least forindoor operation and IP 55 for outdoor operation.



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5.10 MAINTENANCE AND CHECKS

5.10.1. MAINTENANCE

The electrical equipment of a hoisting appliance should be maintained in good condition.Maintenance should be based on the duty class and load spectrum of the hoisting applianceand carried out in accordance with the instructions of the supplier or manufacturer.

In addition to the checklists in 5.10.2, requirements for maintenance instructions andpractices can be found e.g. in ISO 12480-1 and EN 12644-1.

5.10.2. CHECKS

A distinction is made between regular checks and checks made before the appliance iscommissioned.

Regular checks are subdivided into simple checks and comprehensive checks.

5.10.2.1. REGULAR CHECKS

5.10.2.1.1. Simple checks

The safety devices which can be checked from the control position are to be checkedregularly, in principle before the start of each workday, for their proper electric functioning.

In particular, the following, at least, must be checked :− emergency limit switches,− brake functions,− emergency stop.

5.10.2.1.2. Comprehensive checks

At least once a year, the electrical equipment of a hoisting appliance should be given acomprehensive check.

Besides the above simple checks, the following should be checked thoroughly :— the settings and conditions of the electrical safety devices,— integrity of protective earth systems,— integrity of equipotential circuits,— insulation of all the electrical equipment,— tightness of all connections,— predetermined resistance values, if any,— physical condition of cables and cable inlets,— physical condition of safety devices,— presence and condition of devices protecting against direct contact,— the technical performance of replaced parts is compatible with the proper functioning of

the hoisting appliance.



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5.10.2.2. CHECKS BEFORE COMMISSIONING

In addition to the comprehensive checks, the checks before commissioning include, at least :— checking that all the hoisting appliance’s electrical equipment is in conformity with

regulations and standards,— checking that the electrical equipment agrees with the circuit diagrams,— checking the switching sequence of the safety and control circuits,— checking the proper functioning of the electrical components— checking that the control system does not permit any uncontrolled excess speeds in

normal operation,— checking the correct settings for all the electrical equipment and its proper functioning.

5.11 AUXILIARY ELECTRICAL EQUIPMENT

In addition to the requirements of EN 60204-32 clause 16 the following clauses apply.

5.11.1. LIGHTING

5.11.1.1. CABIN

A fixed non-dazzling service lighting should be provided, so arranged that only the necessaryillumination for the lighting of the control equipment is provided.

When the general area lighting equipment is not sufficient to permit access and exit out of thecabin in safety, supplementary portable lighting should be provided ; this equipment must beable to work, even if the principal electrical circuits of the crane are isolated.

5.11.1.2. WORKING AREA LIGHTING

When the working area lighting is provided by the appliance, projectors should be suitablyplaced on the crane, so that a minimum illumination of 30 lux at ground level is guaranteed.

This lighting circuit should be independent of the principal circuits of the hoisting appliance.

Precautions must be taken to avoid voltage drops produced by starting the motors cutting outthe gas discharge lamps.

5.11.1.3. ACCESS AND MACHINERY CABINET LIGHTING

When the general area lighting does not permit sufficient illumination, supplementary lightingindependent of the principal circuits of the hoisting appliance should be provided. Theminimum illumination should be 30 lux.

5.11.1.4. EMERGENCY LIGHTING

When the lighting of the area does not permit exit out of the appliance in safety, a portablelamp, equipped with batteries should be provided. A battery charger must be provided in thecabin.



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5.11.2. HEATING AND AIR-CONDITIONING

5.11.2.1. MACHINERY CABINETS

Natural or forced ventilation should be provided to disperse thermal power generated by themachinery and its equipment.

Where electronic equipment is used and working conditions do not guarantee an ambienttemperature for proper functioning of the electronic equipment, an air conditioning unit shouldbe provided.

5.11.2.2. CABIN

If necessary heating appliances should be provided in the cabin.

This apparatus of black heat/non-radiant type shall be securely fixed. It must be provided witha thermostat and must have such a power to assure a minimum temperature of 15° C, takinginto account the environment in which the equipment is installed. This apparatus must be fedindependently of the principal circuits of the hoisting appliance.

If required by the environment an air conditioning unit should be installed in the cabin tomaintain a maximum acceptable temperature. This apparatus must be fed by a circuitindependent of the principal circuits of the hoisting appliance.

5.11.3. AUXILIARY CIRCUIT

If there is no possibility of supply in the proximity, auxiliary circuits should be provided formaintenance purposes, as follows :

− A circuit for portable lighting, if the ambient lighting is not sufficient to carry outmaintenance.

− A circuit for portable tools according to agreement between customer and supplier.

− These circuits should be protected by a differential circuit breaker of high sensitivity andthey should be independent of the principal circuits of the hoisting appliance.

- : -




SECTION I


F.E.M.

1.001 3rd EDITION

REVISED

1998.10.01


HOISTING APPLIANCES

B O O K L E T 7

SAFETY RULES





Booklet 7

SAFETY RULES7.1. SCOPE..................................................................................................................................................4

7.2. BASIS OF CALCULATIONS...............................................................................................................4

7.3. MARKING AND PLATES.....................................................................................................................4

7.3.1. RATING PLATE............................................................................................................................4

7.3.2. MANUFACTURER'S PLATE ......................................................................................................5

7.3.3. WARNING NOTICES ..................................................................................................................5

7.4. CONSTRUCTION REQUIREMENTS..................................................................................................6

7.4.1. CLEARANCES.............................................................................................................................67.4.1.1. Safety distances....................................................................................................................... 67.4.1.2. Longer clearance...................................................................................................................... 67.4.1.3. Upper clearance ....................................................................................................................... 6

7.4.2. DRIVER'S CABS IN GENERAL.................................................................................................67.4.2.1. Driver’s visibility ........................................................................................................................ 67.4.2.2. Cab’s dispositions..................................................................................................................... 77.4.2.3. Heat-insulating material ............................................................................................................. 77.4.2.4. Glazed windows and entrances.............................................................................................. 77.4.2.5. Anti-glare lighting and heating................................................................................................... 77.4.2.6. Heat-proof................................................................................................................................. 87.4.2.7. Clean air supply ........................................................................................................................ 8

7.4.3. ADDITIONAL REGULATIONS REGARDING HOIST-SUSPENDED DRIVER'S CABS....87.4.3.1. Plate indication .......................................................................................................................... 87.4.3.2. Inopportune motions.................................................................................................................. 87.4.3.3. Suspended driver's cabins....................................................................................................... 87.4.3.4. Lowering speed limit................................................................................................................. 87.4.3.5. Controls..................................................................................................................................... 97.4.3.6. Limit switches........................................................................................................................... 97.4.3.7. Buffers...................................................................................................................................... 97.4.3.8. Distress signal .......................................................................................................................... 97.4.3.9. Safety headroom ...................................................................................................................... 97.4.3.10. Remote control........................................................................................................................ 9

7.4.4. GANGWAYS AND PLATFORMS..............................................................................................107.4.4.1. Cab access............................................................................................................................. 107.4.4.2. Indirect access ....................................................................................................................... 107.4.4.3. Access to gangways, stairways and platforms.................................................................... 107.4.4.4. Maintenance areas ................................................................................................................. 107.4.4.5. Raised locations areas ........................................................................................................... 107.4.4.6. Erection, dismantling, testing, repairs and maintenance work’s areas................................... 117.4.4.7. Lowered work’s areas........................................................................................................... 117.4.4.8. Headroom................................................................................................................................ 117.4.4.9. Guard rails .............................................................................................................................. 117.4.4.10. Slip-proof surfaces............................................................................................................... 127.4.4.11. Power lines protections........................................................................................................ 12



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7.4.5. STAIRWAYS AND LADDERS ..................................................................................................127.4.5.1. General ................................................................................................................................... 127.4.5.2. STAIRWAYS........................................................................................................................... 127.4.5.3. LADDERS................................................................................................................................ 13

7.5. MECHANICAL DEVICES...................................................................................................................14

7.5.1. ROPE AND CHAIN DRIVES ....................................................................................................147.5.1.1. Drums...................................................................................................................................... 147.5.1.2. Lowest hook position.............................................................................................................. 147.5.1.3. Ropes...................................................................................................................................... 147.5.1.4. Chains..................................................................................................................................... 14

7.5.2. HOOK BLOCKS, PULLEYS AND OTHER LOAD CARRYING DEVICES ........................157.5.2.1. Prevent to jumping................................................................................................................... 157.5.2.2. Hand guard ............................................................................................................................. 157.5.2.3. Maintenance............................................................................................................................ 157.5.2.4. Accidental un-hooking protection ........................................................................................... 157.5.2.5. Working load plate................................................................................................................... 15

7.5.3. BRAKES......................................................................................................................................157.5.3.1. General ................................................................................................................................... 157.5.3.2. Hoisting brake ......................................................................................................................... 167.5.3.3. Travel and crab brakes........................................................................................................... 167.5.3.4. Slewing brake......................................................................................................................... 177.5.3.5. Luffing brake........................................................................................................................... 17

7.6. HYDRAULIC EQUIPMENT ................................................................................................................18

7.6.1. Pipes ...........................................................................................................................................18

7.6.2. Cylinders.....................................................................................................................................18

7.6.3. Working pressure .....................................................................................................................18

7.6.4. Pollution......................................................................................................................................18

7.6.5. Pressure gauge ........................................................................................................................18

7.6.6. Breathers....................................................................................................................................18

7.6.7. Limit positions...........................................................................................................................19

7.6.8. Bursting pressure.....................................................................................................................19

7.6.9. Hydraulic fluid ............................................................................................................................19

7.6.10. Unintentional start-up ............................................................................................................19



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7.7. SAFETY DEVICES..............................................................................................................................20

7.7.1. DEVICES FOR LIMITING WORKING MOTIONS ..................................................................207.7.1.1. HOIST MECHANISMS............................................................................................................... 207.7.1.2. TRAVEL DRIVES..................................................................................................................... 207.7.1.3. LUFFING AND SLEWING MECHANISMS........................................................................... 21

7.7.2. SAFETY AGAINST OVERLOADING AND OVERTURNING ................................................217.7.2.1. Derailment safety devices ...................................................................................................... 217.7.2.2. Overload protection ................................................................................................................ 227.7.2.3. Load chart............................................................................................................................... 22

7.8. AGEING OF APPLIANCES................................................................................................................23



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7.1. SCOPE

These rules are applicable to cranes and heavy lifting appliances covered by clause 1.4. ofbooklet 1 - "Object and Scope" 1.

7.2. BASIS OF CALCULATIONS

The calculation of crane structures and mechanisms shall be in accordance particularly withbooklet 3-"Design stresses in the structure" and booklet 4 "Design and choice of mechanismcomponents".

7.3. MARKING AND PLATES

Lifting appliances shall bear the following markings or plates, in the language of the country inwhich the appliance will operate, or in a language accepted by the user.

7.3.1. RATING PLATE

The lifting capacity (and radius where applicable) shall be permanently marked in a visibleposition and shall be easily legible from the ground.

The lifting capacity shall be the heaviest mass which may be hoisted by the crane, or by anyhoisting accessory, either permanent or incorporated under certain conditions ; in the case ofgrabbing cranes, the lifting capacity shall be the permissible total weight of the grab andcontents.

In the case of luffing cranes, the lifting capacity corresponding to each radius shall be indicatedin durable form showing appropriate graduations, and shall be clearly legible from the ground.More detailed indications of permissible loads at different radii shall be obtainable from themanufacturer's operating manual.

In the case of cranes with more than one hoist, the lifting capacity of each hoist shall be indicatedon the relevant hook block. It should furthermore be indicated if all the hoists can be used at thesame time.

1 For builders tower cranes, the safety measures in preparation by the E.E.C. are also accepted by theF.E.M.



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7.3.2. MANUFACTURER'S PLATE

Each lifting appliance, independent crab or winch shall be fitted at a convenient point with themaker's plate, detailing the following :

- name of manufacturer,- year of manufacture,- manufacturer's serial number,- lifting capacity in kgs and/or tonnes,- type.

7.3.3. WARNING NOTICES

A notice reading : "Do not stand under the load" shall be suitably located so as to be clearlyvisible. Crane access points shall be marked with a notice reading : "No access forunauthorised personnel". Particularly dangerous areas shall be marked with a notice reading :"Danger - Crane" and, where necessary, by means of warning colour stripes.



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7.4. CONSTRUCTION REQUIREMENTS

7.4.1. CLEARANCES

7.4.1.1. Safety distances

All moving parts of lifting appliances, with the exception of handling and grabbing devices, in theirmost unfavourable position and under the most unfavourable loading conditions shall be at least0,05 m from any fixed part of a building, at least 0,1 m from any guard rail or handrail and aminimum of 0.5 m from access areas. Access areas are all access ways authorised topersonnel. This does not apply to working platforms. For railway loading profiles, the appropriateloading gauge shall be used and there shall be a minimum clearance of 0,5 m in access areas.Under no circumstances shall fixed parts of any lifting appliance encroach upon the railwayclearance gauge.

7.4.1.2. Longer clearance

The minimum vertical distance between the longer clearance line of a lifting appliance and areasof general access below (from the floor as well as from fixed or movable equipment belonging tothe building, with the exception of working or service platforms or similar shall be at least 1.8 min areas of general working access. From parts of stationary or mobile installations with limitedwalk-on or step-on access (such as roofs, heaters, machinery parts and cranes travelling belowetc.) as well as from guard rails, the minimum vertical distance shall be 0,5 m.

7.4.1.3. Upper clearance

The minimum vertical distance between the upper clearance line of a lifting appliance and fixedor moving parts above (e.g. between crab structures or guard-rails on the one hand and roofjoists, pipelines or lifting appliances travelling overhead on the other) shall be not less than 0,5m in maintenance areas and in the vicinity of platforms. This distance may be reduced to 0,1 min the case of individual structural members, provided no danger to personnel results or thatadequate precautions are taken to eliminate the risks.

7.4.2. DRIVER'S CABS IN GENERAL

7.4.2.1. Driver’s visibility

Driver's cabs shall be designed so that the driver has a clear view of all work areas or so that hemay adequately follow all operations with the aid of suitable equipment.



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7.4.2.2. Cab’s dispositions

The driver's cab shall have sufficient room for the driver to be able to reach or leave the controlswithout hindrance. Controls shall preferably be operated from a sitting position, but also from astanding position when necessary.

Driver 's cabs shall have a minimum headroom of 1,9 m and shall be fitted with a guard rail of atleast 1,0 m high.

Outdoor cabs, or those operating in unheated bays, shall be of enclosed construction, except inwarm climates. Driver's cabs in heated bays, or which are seldom used or of an auxiliary naturemay be of open construction.

A protective shield shall be installed above the driver 's cab when there is any danger of fallingobjects.

The layout of the cab and controls shall be ergonomically designed.

7.4.2.3. Heat-insulating material

The structural framework of the driver's cab shall be of non-combustible material, and the sidepanels and roof may optionally be of fire resistant materials. The floor of the driver's cab shall becovered with non-metallic, heat-insulating material.

7.4.2.4. Glazed windows and entrances

In cabs with windows less than 1,0 m from the floor and glazed areas in the floor, the glazingshall be constructed or protected to a height of 1,0 m so that personnel cannot fall through them ;walkover windows shall be tread proof.

Entrances shall be protected against accidental opening. Sliding doors and outward openingdoors of driver's cabs must lead on to landings.

It must be possible to clean the windows of the driver's cab without risk. Glazed openings let intothe floor of the driver's cab and those which are exposed to an increased risk of breakage orsubjected to heat radiation when the crane is in operation shall be made of suitable safety glass.

7.4.2.5. Anti-glare lighting and heating

Driver's cabs shall be provided with adequate anti-glare lighting to allow handling of the controlsand, if necessary, can be ventilated.

Enclosed driver's cabs for outdoor operation and cabins located in unheated bays must beprovided with heating.



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7.4.2.6. Heat-proof

Driver's cabs which are exposed to radiant heat shall be protected against heat radiation and ofa heat-proof design, and they shall be air-conditioned in order to ensure tolerable workingconditions.

7.4.2.7. Clean air supply

Driver's cabs exposed to conditions presenting a health hazard, such as dust, vapours or gases,shall be protected against their entry and provided with a clean air supply.

7.4.3. ADDITIONAL REGULATIONS REGARDING HOIST-SUSPENDED DRIVER'SCABS

7.4.3.1. Plate indication

The permitted number of persons and maximum load of the driver's cab shall be permanentlyand clearly indicated. Additional "Operating and maintenance instructions for hoist-suspendeddriver's cabs" shall be posted in the cab.

7.4.3.2. Inopportune motions

It must not be possible for the driver's cab to spin or swing dangerously.

7.4.3.3. Suspended driver's cabins

Hoist suspended driver's cabins shall be provided with an anti-fall device. Alternatively, there maybe two independent means of suspension, provided that the driver's cabin remains secureshould one means of suspension break, or should the drive or service brake fail. Each individualmeans of suspension shall be designed with a safety factor of not less than five times the fullworking load.

If there is an anti-fall device and only one means of suspension, a minimum safety factor of eightis necessary.

Rope drives shall be designed as a minimum in accordance with mechanism group M8. Thediameter of the rope shall be not less than 6 mm. Ropes for outdoor duty shall be made ofgalvanised steel wire.

7.4.3.4. Lowering speed limit

On reaching a speed of 1.4 times the nominal lowering speed the driver's cab shallautomatically be brought to a halt.

The driver's cab must be able to move independently of the load.



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7.4.3.5. Controls

All controls shall stop automatically as soon as the driver releases them.

7.4.3.6. Limit switches

Normal and emergency limit switches shall be provided for the highest and lowest positions ofthe cab, with separate switching and operating systems.

Emergency limit switches shall directly switch off the main power circuit and activate an audiblewarning signal.

In the event of the driver 's cab striking an obstacle or a suspension means becoming slack, allcrane motions shall automatically shut down. Devices for returning the crane to service shall notbe of self re-setting type.

7.4.3.7. Buffers

If the travel speed of the driver's cab is greater than 40 m/min, devices shall be provided toreduce the speed promptly so that the buffers cannot be struck at a speedgreater than 40 m/min. If the impact velocity is greater than 20 m/min, energy absorption buffersshall be provided.

7.4.3.8. Distress signal

The driver 's cab shall be provided with a distress signal system independent of the electricalsupply of the crane.

It shall also be provided with a mean of emergency descent, e.g. a rope ladder or escapeapparatus, which is always in the cab.

7.4.3.9. Safety headroom

The user shall ensure that with the maximum stacking height of goods there is a safetyheadroom of 0,5 m to the underside of the driver's cab in its working position.

7.4.3.10. Remote control

It must only be possible to remotely operate the crane from the ground with the driver's cab in itshighest working position (see also 7.7.).



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7.4.4. GANGWAYS AND PLATFORMS

7.4.4.1. Cab access

Easy and safe access to the driver's cab must be possible with the lifting appliance in anyposition under normal working conditions. If the floor of the driver's cab is less than 5 m aboveground level, access may be restricted to certain positions of the lifting appliance, provided thedriver's cab is fitted with appropriate emergency exit means, e.g. a rope ladder.

Entry to the driver's cab should be preferably from a platform at the same level as the floor of thecab and provided with guard rails. Entry through the floor, or through the ceiling of the driver's cabshall be permissible only when necessitated by virtue of space restrictions.

Where entry is made directly via a staircase, a platform or a gangway, the horizontal gap to thedriver's cab entrance shall not exceed 0,15 m and the difference in level between the platformand the driver's cab floor shall not exceed 0,25 m.

7.4.4.2. Indirect access

When the driver's cab cannot be reached directly from ground level in any position of the crane,and where the driver's cab floor is higher than 5 m from ground level, the crane installation shallbe provided with appropriate gangways. For certain appliances, such as overhead travellingcranes, access may be limited to certain positions of the crane, if appropriate devices areprovided which enable the driver to leave the cab.

7.4.4.3. Access to gangways, stairways and platforms

Gangways, stairways, and platforms must have safe access with the lifting appliance in anyposition. Stairways and ladders in frequent use shall lead on to platforms or gangways. For suchaccess, stairways are preferable to ladders.

7.4.4.4. Maintenance areas

All operating locations and all equipment of the crane which requires regular inspection ormaintenance must be provided with safe access, or be reached by means of portable workplatforms.

7.4.4.5. Raised locations areas

The above-mentioned locations when more than 2 m above floor level, and also crane jibs mustbe accessible via stairways, platforms, walkways or ladders. Steps shall be fitted with guard railson both sides (see also 7.4.5.2.).



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7.4.4.6. Erection, dismantling, testing, repairs and maintenance work’s areas

When work is carried out during erection, dismantling, testing, repairs and maintenance atpoints situated more than 2 m above floor level, appropriate measures shall be taken on cranesand jibs to ensure the safety of personnel (such as handrails, handgrips, safety devices, etc.)and to permit access of personnel to these points. Pulleys and moving parts placed at the end ofjibs shall be designed so that no lubrication is necessary between erecting and dismantling thecrane. If this is not the case, the jib must be provided with access.

7.4.4.7. Lowered work’s areas

The above-mentioned access to the jib may be omitted when the latter can be lowered for thepurpose of a complete visual check or when other constructions permit a visual check.

7.4.4.8. Headroom

Stairways, gangways and platforms shall have a headroom of not less than 1,8 m. A clearpassageway not less than 0,5 m wide must be provided in the vicinity of driven parts which moverelative to gangways and platforms ; this dimension may be reduced to 0,4 m up to a height of0,6 m by providing a handrail. The clear width of passage way between stationary parts shall benot less than 0,4 m.

The clear headroom of little used access ways inside crane structures may be reduced to aminimum of 1,3 m, whilst at the same time the width shall be increased to 0,7 m, varying linearlywith the reduction in height. The headroom above platforms used only for maintenancepurposes may be reduced to 1,3 m.

7.4.4.9. Guard rails

Parts of crane installations with access shall be provided with continuous guard rails on thosesides where there is a danger of falling from a height of over 1 m. Toe guards shall be not lessthan 0,1 m high. Openings in guard rails shall be permissible where adequate protectivemeasures against falling are provided. Guard rails shall, as a rule, be not less than 1 m highand shall be provided with toe guards and intermediate rails. The height of the guard rails maybe reduced to 0,8 m for passage ways where a clear height of 1,3 m is permissible. Alonggangways there shall be at least one handrail.

For gangways alongside building walls or a solid wall construction, handrails shall bepermissible in lieu of guard rails. Interruptions in the length of these shall not exceed 1 m (e.g.for building columns, door openings).



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7.4.4.10. Slip-proof surfaces

Platform surfaces shall be suitably slip-proof. Holes, gaps and openings in the flooring shall berestricted in size so that a 0,02 m diameter ball cannot pass through.

Gangways which are less than 0,5 m above exposed power lines must be provided with solidflooring in those areas.

7.4.4.11. Power lines protections

When gangways are located adjacent to power lines, these lines must be protected againstaccidental contact.

7.4.5. STAIRWAYS AND LADDERS

7.4.5.1. General

Stairways and ladders shall be provided wherever the difference in level exceeds 0,5 m.

Footholds provided with hand grips may be installed on vertical surfaces where the height doesnot exceed 2 m (e.g. end carriages).

Ladders shall be interrupted by intermediate landings if they exceed a height of 8 m. For greatheights as, for example, tower cranes for building, additional intermediate platforms may beprovided for which the vertical interval must be a maximum of 8 m. Where there are spaceproblems, a single continuous ladder with platforms alongside may be installed.

7.4.5.2. STAIRWAYS

The slope of stairways shall not exceed 65°, the height of individual steps shall not exceed 0,25m (0,2 m for tower cranes) and their depth shall not be less than 0,15 m. If possible, thefollowing ratios shall be observed :

2 . step height + 1 tread width = 0,63 m

The height interval between steps shall be constant. In the case of main stairways the guard railposts shall be spaced not less than 0,6 m apart, but in the case of other stairways 0,5 m shallsuffice.

Surface of treads shall be anti-slip.

Stairways shall be provided with guard rails on each side ; where there is a wall on one side ofthe stairway a handrail shall be sufficient on the wall side.



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7.4.5.3. LADDERS

The length of rungs between side frames shall be no less than 0,3 m ; their pitch shall beconstant and not exceeding 0,3 m. The rungs shall be at least 0,15 m away from fixed structuralmembers. A rung shall be able to withstand a force of 1200 N at the centre without sufferingpermanent deformation.

Climb-through openings shall not be smaller than 0,63 m x 0,63 m or less than 0,8 m indiameter.

Ladders over 5 m in height shall be provided with safety hoops starting at a height of 2,5 m.

The distance between safety hoops shall be not greater than 0,9 m. They must beinterconnected by at least three equally spaced longitudinal stringers. In all cases, onelongitudinal stringer must be placed at a point which is exactly opposite the vertical centre line ofthe ladder.

The strength of safety hoops, reinforced by the longitudinal stringers, must be adequate towithstand a force of 1000 N distributed over 0,1 m acting on any point of the hoop, without anyvisible deformation.

The sides of ladders shall extend at least 1 m above the top rung, unless some otherappropriate handhold is provided. Where space is limited, 0,8 m shall be acceptable.

Safety hoops are not necessary on ladders placed on the inside of structures which can act as asafety guard and where there is a clearance of 0,7 m to 0,8 m between the ladder and theopposite side. Structural members can be considered equivalent to safety hoops provided theyare arranged so that the perpendicular distance between bars in the danger zone is always lessthan 0,75 m and the inscribed circle between the ladder and the struts is less than 0,75 m.

The ladders must be provided with rest platforms spaced so that the first stretch does notexceed 10 m and there are then rest platforms at every 8 m.



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7.5. MECHANICAL DEVICES

7.5.1. ROPE AND CHAIN DRIVES

7.5.1.1. Drums

Rope drums shall be provided with rope grooves. The rope, as a rule, shall be wound in onelayer. If winding is done in more than one layer, an appropriate spooling device or windingsystem shall be provided ; such a device is not necessary in the case of two layers where therope is self-guided during winding.

If there is a possibility of the rope becoming slack on the drum during operation or of not beingwound on properly, means shall be provided to prevent this.

Drums shall be provided with end flanges unless other measures are taken to prevent the ropesfrom overriding the ends or falling.

The diameter of the flanges of the drum shall be such that, with the rope fully wound on, theflange shall project a distance of not less than one-and-a-half rope diameters above the top layerof the rope (for builders cranes, twice the rope dia).

7.5.1.2. Lowest hook position

At the lowest permissible hook position, there shall still be at least two turns on the drum beforethe rope anchorage. If the rope end is fastened to the drum with bolted clamps, there shall be atleast two separate clamps held by bolting fitted with positive locking devices.

7.5.1.3. Ropes

Ropes shall be protected wherever possible against the influence of direct radiant heat andagainst being sprayed with molten and other dangerous substances. Special ropes shall beused when operating under conditions of excessive influence of heat, corrosive materials etc...

7.5.1.4. Chains

Chain drives shall be provided with a device ensuring smooth running of the chain on thesprocket wheel and preventing it from jumping. An effective chain guard shall be provided.



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7.5.2. HOOK BLOCKS, PULLEYS AND OTHER LOAD CARRYING DEVICES .

7.5.2.1. Prevent to jumping

Adequate means shall be provided to prevent the rope or chain from jumping off the pulleys.

7.5.2.2. Hand guard

An adequate guard shall be provided where there is any danger of a hand being trappedbetween the rope and the pulley of the hook block.

7.5.2.3. Maintenance

Rope pulleys shall be designed so as to be accessible for maintenance.

7.5.2.4. Accidental un-hooking protection

Safety hooks or specially designed hooks shall be required where the method of operationinduces increased danger of accidental un-hooking of the load or of the hook becomingsnagged.

7.5.2.5. Working load plate

Interchangeable load carrying devices, such as grabs, lifting magnets, buckets, tongs andbeams, shall be permanently marked with their safe working load and dead weight and also, inthe case of grabs and buckets for bulk materials, with their capacity and name of manufacturer.

7.5.3. BRAKES

The provisions of this clause shall not apply to cylinder operated mechanisms e.g. hydraulic jackhoists.

7.5.3.1. General

Drives shall be provided with mechanical brakes. If in exceptional cases the drive is through aself-locking gear, the brake may be omitted, provided it has been ensured that no excessivestresses or movements can occur.

Brake mechanisms shall be easy to inspect. Brake springs shall be of the compression type.

Brakes must be adjustable and brake linings must be replaceable.



7 - 16

7.5.3.2. Hoisting brake

Hoist units must be provided with brakes which are automatically applied and which can safelyhold the test load in the event of switching off or failure of the hoist drive.

Brake systems shall be designed for 1,6 times the hoist load and they shall be capable ofbraking the dynamic test load without a damaging snatch effect and without unacceptableoverheating.

Brakes of hoist units shall be arranged so that there is a positive mechanical link between thewinch components which, on the one hand, generate the braking moment and, on the otherhand, support the load.

The electrical and mechanical gear shall make it possible to keep the lowering speed underload within the permissible limits.

Hoist units for carrying molten materials shall be provided with two mechanical brakes whichoperate independently of each other, each of which shall meet the preceding requirements ; thesecond brake shall be applied with a time lag in relation to the first one.

In special critical cases where failure of a driving unit must be catered for the second brake shallact on the rope drum ; this brake shall be so controlled that it is applied automatically, not laterthan the instant a speed of 1,5 times the nominal lowering speed has been reached. In suchcases the control gear of the crane shall include an emergency stop which shall also activate thebrake.

7.5.3.3. Travel and crab brakes

Power driven travel drives of cranes and crabs shall be equipped with an automatic brake, or abrake which may be operated from the control position. Excluded from this category are cranesnot subjected to wind, operating on a horizontal track at a speed not exceeding 40 m/min., orwhen on wheels with antifriction bearings, not exceeding 20 m/min. For cranes intended to carrymolten materials, a brake is required independently of speed.

The brakes must be so designed that the crane or crab can be brought to rest in a suitable timeand held stationary in all operating conditions, under wind load when applicable and also in thecase of power failure.

Non-automatic travel brakes of cranes and crabs exposed to the wind shall be provided with aclamping device.

Automatic travel brakes or anchoring devices shall be designed with a factor of safety not lessthan 1.1 against the maximum forces in out of service conditions.



7 - 17

7.5.3.4. Slewing brake

Power driven slewing drives shall be provided with brakes designed to bring to a halt, in asuitable time and to hold the slewing part stationary in all service conditions, under wind loadwhen applicable and in the event of power failure.

7.5.3.5. Luffing brake

Luffing systems shall be provided with brakes designed so that in the event of shut down orfailure of the luffing gear drive they shall be applied automatically and safely hold the jib with thetest load in the most unfavourable position.

Brake mechanisms shall be designed for a minimum braking moment equivalent to 1,6 timesthe moment due to the hook load and the dead weight of the jib system plus 1,0 times themoment due to the wind load, in the most unfavourable operating configuration (i.e. maximumwind load in service).

For the crane out of service this shall be at least 1,1 times the moment due to the dead weight ofthe jib system and due to the wind (max. out of service storm wind) in the most unfavourable jibposition or in a specified out of service jib position.



7 - 18

7.6. HYDRAULIC EQUIPMENT

7.6.1. Pipes

Precision seamless steel pipe shall be used for pressure lines up to 3 cm outer diameter ; nowelding shall be done on these except for welding on the flanges of bolted connections.

7.6.2. Cylinders

When hoisting and luffing mechanisms are driven by hydraulic jacks, automatic devices (burstprotection valves) shall be installed immediately adjacent to the connections to pressure lines toavoid any undesirable lowering of the load, particularly in the event of pipe failure. When there isa risk of dangerous lowering of the load due to oil leakage or leaking components, mechanicaldevices shall be provided to prevent this.

With other hydraulic drives, the above motions must be stopped by means of automatic brakes,actuated by self-resetting controls, as specified under paragraph 7.5.3.

7.6.3. Working pressure

Exceeding of the maximum specified working pressure shall be prevented by means of

pressure relief valves. Appropriate provisions or constructional measures shall betaken to prevent the working pressure from being exceeded by more than 1.6 times,including the case of transient peak pressure.

7.6.4. Pollution

Prior to start-up, the hydraulic system shall be free from foreign bodies such as turnings,sprinters or scale. The system shall be designed so that such foreign bodies can be readilyremoved when making repairs.

7.6.5. Pressure gauge

Each hydraulic circuit shall have at least one connection outlet for a pressure gauge, enablingthe measurement of pressure without any dismantling of pipework.

7.6.6. Breathers

Hydraulic systems shall be fitted with breathers at suitable points.



7 - 19

7.6.7. Limit positions

Overrunning of limit positions shall be prevented by means of appropriate devices.

7.6.8. Bursting pressure

Pipework and hoses must be designed with a factor of safety of four against bursting pressure ;this applies also to connections and flange joints. For stationary lifting appliances which are freefrom hydraulic shocks and vibration , a factor of safety of 2,5 shall suffice.

7.6.9. Hydraulic fluid

Hydraulic fluid used in the hydraulic installations of cranes and winches shall comply with therequirements of service conditions and with the technological and safety requirements. Thehydraulic fluid shall be specified to the user. It must be possible to check the maximum andminimum levels of the hydraulic tank.

7.6.10. Unintentional start-up

Unintentional start-up of drives following the renewal of power supply after failure or theswitching on of the isolator switch or of the main crane switch must be prevented ; e.g. by meansof electrical interlocks or by means of an automatic mechanical return of the controller.



7 - 20

7.7. SAFETY DEVICES

7.7.1. DEVICES FOR LIMITING WORKING MOTIONS

7.7.1.1. HOIST MECHANISMS

The range of power driven hoist mechanisms shall be restricted at the highest and the lowestpermissible positions of the load supporting means by automatic limit switches (emergencylimit switches), having regard to the distance required to slow clown. The return from the limitpositions must be possible by means of the controller. If a limit position is reached duringnormal operation, there shall be an additional and independent service limit switch. In this case,when the service limit switch has been tripped, it shall be possible to effect the return movementby use of the controller, but if the emergency limit switch has been tripped, this return movementshall not be possible.

Hoists powered by an internal combustion engine and mechanically coupled with nonintermediate electrical, hydraulic or pneumatic link may be provided with visual or acousticwarning devices instead of limit switches.

7.7.1.2. TRAVEL DRIVES

Power driven cranes and crabs shall be provided with devices such as shoe brakes, rubber,spring or hydraulic buffers or other special devices, which are capable of absorbing one half ofthe energy of the moving masses at normal travelling speed and such that the maximumdeceleration in the driver 's cab does not exceed 5 m/sec2.

If the limit of travel is frequently reached during normal operation, the maximum deceleration inthe driver 's cab shall not exceed 2,5 m/sec2.

Cranes and crabs with radio control shall be provided with limit switches when the travel speedsare in excess of 40 m/min.

Cranes and crab mounted driver's cabs, which are subject to wind, shall be provided with stormanchors for "Out of Service" conditions.

When operating conditions require that certain wind conditions be taken into account in theoperation of the crane, a wind indicator and alarm must be provided on the crane.

Cranes shall be fitted with rail sweeps where material obstructions can come to rest in the track.



7 - 21

When two or more cranes run on the same track special devices shall be provided to prevent adangerous collision. Under no circumstances shall the deceleration in the driver's cab exceed 5m/sec2.

In areas which are dangerous due to their being within the operational area of cranes or crabs,adequate measures shall be taken to protect personnel ; e.g. by the use of warning notices,flashing lights, acoustic warnings or, if necessary, automatic stopping devices.

7.7.1.3. LUFFING AND SLEWING MECHANISMS

With power driven luffing mechanisms the movement of the jib at the limit of the travel shall berestricted by means of automatic limit switches (emergency limit switches) having regard to thedistance required to slow clown.

The return from the limit positions must be possible by means of the controller.

Luffing mechanisms powered by an internal combustion engine and mechanically coupled withno intermediate electrical, hydraulic or pneumatic link, may be provided with visual or acousticwarning devices instead of limit switches.

Similarly, power driven slewing mechanisms with-limited slewing range shall have the slewingmovement limited by means of an automatic emergency limit switch.

Furthermore, there shall be devices in accordance with the spirit of the provisions of paragraph7.7.1.2. at the limits of travel of restricted slewing range or luffing range.

7.7.2. SAFETY AGAINST OVERLOADING AND OVERTURNING

7.7.2.1. Derailment safety devices

Cranes and crabs shall be so designed, or provided with such additional safety devices that,even in the event of derailment or failure of a runner wheel or a wheel shaft or bearing, themaximum drop is limited to 3 cm and falling or overturning is prevented.

In addition, exceptional forces such as those due to impact on buffers, collision and erectionshall not cause the crane or the crab to overturn or fall.



7 - 22

7.7.2.2. Overload protection

Cranes and trolleys equipped with jibs and outriggers which can overturn due to an overload,and having a load lifting capacity independent of radius, shall be provided with an overloadprotection switch ; however, when the load lifting capacity varies with the outreach, the switchshall also act as a load moment switch. It should be possible to return into the permissiblerange of the load moment by reversing the movement or, where the overload has been causedby lifting the load, by setting it down using the controller.

Cranes with hoists and/or luffing mechanism powered by an internal combustion engine andmechanically coupled with no intermediate electrical, hydraulic or pneumatic link may beprovided with a visual or acoustic warning device instead of an overload switch.

7.7.2.3. Load chart

Cranes and lifting appliances with the lifting capacity dependent on radius shall be provided witha permanent notice, clearly visible from the driving position and stating, in suitable graduations,the hook loads corresponding to the various radii.



7 - 23

7.8. AGEING OF APPLIANCES

Like other machines and lifting appliances, those pertaining to Section I of the FEM are alsodesigned for a certain duration of life.

They are, in addition, covered by Design Rules which have been developed from the scientificknowledge and experience of users and manufacturers for application to the various types ofappliances.

This notion of ageing applies mainly to the structure and the mechanisms, and not so much tothe consumable components (such as : ropes, brake linings, brushes, heat engines, etc...).

The principal factors contributing adversely to the ageing of appliances are :

- fatigue phenomena- corrosion- operational, assembly and dismantling accidents- overloading- inadequate maintenance.

The user must always bear in mina the importance of ageing.




SECTION I


F.E.M.

1.001 3rd EDITION

REVISED

1998.10.01


HOISTING APPLIANCES

B O O K L E T 8

TEST LOADS AND TOLERANCES





Booklet 8

TEST LOADS AND TOLERANCES

8.1. TESTS...................................................................................................................................................2

8.1.1. DYNAMIC TEST ...........................................................................................................................2

8.1.2. STATIC TEST ...............................................................................................................................2

8.1.3. NOTE 1..........................................................................................................................................2

8.1.4. NOTE 2..........................................................................................................................................2

8.2. TOLERANCES OF CRANES AND TRACKS .....................................................................................3

8.2.1. MEASURING PROCEDURE .....................................................................................................3

8.2.2. MANUFACTURING TOLERANCES FOR CRANES...............................................................38.2.2.1. Span.......................................................................................................................................... 38.2.2.2. Crane girders camber............................................................................................................... 48.2.2.3. Inclination of the wheel............................................................................................................. 48.2.2.4. Trolley rail center distance........................................................................................................ 48.2.2.5. Difference in height of two opposite points.............................................................................. 58.2.2.6. Bearing surface........................................................................................................................ 58.2.2.7. Vertical axis of the trolley......................................................................................................... 68.2.2.8. Trolley rails linearity .................................................................................................................. 68.2.2.9. Axes of the wheel bores.......................................................................................................... 78.2.2.10. Axle bores of opposite wheels .............................................................................................. 78.2.2.11. Bushed wheels....................................................................................................................... 88.2.2.12. Guide rollers............................................................................................................................ 88.2.2.13. Bushed wheels diameter........................................................................................................ 8

8.2.3. TOLERANCES FOR CRANE TRACKS....................................................................................9

APPENDIX..................................................................................................................................................11

A - 8.1.3. - TEST LOADS FOR CRANES IN SOME EUROPEAN COUNTRIES .........................11



8 - 2

.

8.1. TESTS

Prior to being placed in service, appliances must be tested under overload conditions, as follows:

8.1.1. DYNAMIC TEST

The dynamic test shall be carried out with an overload coefficient ρ1 = 1,2 i.e. with a load equal to120 % of the safe working load. All motions shall be carefully operated in turn, without checkingspeeds of temperature rises in the motors (see clause 2.3.3.c).

8.1.2. STATIC TEST

The static test shall be carried out with an overload coefficient ρ2 = 1,4 i.e. with a load equal to140 % of the safe working load. This test must be carried out under still conditions and consistsin hoisting the safe working load to a small distance above the ground and then adding therequired surplus without shock (see clause 2.3.3.c.).

8.1.3. NOTE 1

The figures given for these test loads represent minimum requirements. Where nationallegislation or rules call for higher values, these must be complied with insofar as appliancesdestined for such countries are concerned.

The test to be used in certain countries are given in appendix A-8.1.3. for information.

8.1.4. NOTE 2

When making these tests, it is customary to measure the deflection of the structure of anappliance.

The present rules impose no obligation as to the allowable deflections.

Should the user wish to impose a deflection limit, he must specify this in his call for tenders 1.

1 (1) The custom of regarding small deflection under load as a measure of the strength of an applianceshould be discontinued.

Although an unduly large deflection can adversely affect lattice girders because of the danger of movementat the joints, no untoward effects are to be feared in the case of solid-web or box girders.

In practice, the magnitude of the deflection should be limited only from the standpoint of convenience ofoperation, since vertical oscillations of the load can be troublesome in some cases.



8 - 3

8.2. TOLERANCES OF CRANES AND TRACKS

GENERAL

The use of the Design Rules presupposes that the tolerances specified hereafter for cranes andtracks shall be maintained. These tolerances apply unless other conditions have been agreedwith the user, and take no account of elastic deformations during the operation. The elasticdeformations have to be taken into consideration if required.

The specified tolerances are valid for overhead travelling cranes, gantry cranes and jib cranes,but not for railway cranes. For cranes which have been erected for temporary use only, e.g.building cranes, these rules are only partially valid, in other cases they are to be used judiciously.

8.2.1. MEASURING PROCEDURE

when using measuring tapes, calibrated steel measuring types are to be used. The rules for theuse of these measuring types are to be observed. The readings obtained are to be corrected forthe sag of the tape measure as well as for the divergence of the ambient temperature from thestandard temperature. All measurements on one and the same crane have to be made with thesame tape and the same tension force.

8.2.2. MANUFACTURING TOLERANCES FOR CRANES

8.2.2.1. Span

The greatest divergence ∆s of the crane span’s from the drawing dimension must not exceed thefollowing values :

for s ≤ 15 m : ∆s = ± 2 mm

for s > 15 m : ∆s = ± [ 2 + 0,15 . ( s-15 ) ] mm ( max. ± 15 mm )(s is to be expressed in m)

Figure 8.2.2.1.



8 - 4

8.2.2.2. Crane girders camber

Crane girders, freely supported at their ends, must have no sag, even if the drawing does notprescribe a camber. This means that the track of the trolley with unloaded crane (without trolley)must have no deviation downward from the horizontal. This requirement only applies to craneswith a span longer than 20 m.

8.2.2.3. Inclination of the wheel

In cases where the top of the rail is flat, the inclination of the wheel axis from the horizontal, forthe unladen crane, must be between + 0,2 % and -0,05 %.

Figure 8.2.2.3.

By unladen crane is meant the crane bridge without trolley, freely supported on the endcarriages.

8.2.2.4. Trolley rail center distance

The trolley rail centre distance must not differ from the nominal dimension s by more than ± 3mm.

Figure 8.2.2.4.



8 - 5

8.2.2.5. Difference in height of two opposite points

In a plane perpendicular to the travel direction of the trolley, the difference in height of twoopposite points of the trolley track shall not exceed 0,15 % of the trolley rail centre distance, witha maximum of 10 mm .

Figure 8.2.2.5.

8.2.2.6. Bearing surface

Trolley rails shall be laid in such a way that the running surface is horizontal and that the greatestunevenness of the bearing surface is no more than ± 3 mm for rail centres up to 3 m and nomore than ± 0,1 % of the trolley wheel centre distance if it exceeds 3 m .

Figure 8.2.2.6.



8 - 6

8.2.2.7. Vertical axis of the trolley

The vertical axis of the trolley rail must not diverge from the vertical axis of the rail girder web bymore than half the thickness of the rail girder web .

Figure 8.2.2.7

8.2.2.8. Trolley rails linearity

The axes of the trolley rails must not diverge from their theoretical axis by more than ± 1,0 mm ina rail length of 2 m. There should be no misalignments at rail joints.

Center axis of the trolley rails

Figure 8.2.2.8.



8 - 7

8.2.2.9. Axes of the wheel bores

The axes of the wheel bores must not have an angular deviation greater than ± 0,04 % from itstheoretical axis, in the horizontal plane .

Theoretical positionof all wheels

Figure 8.2.2.9.

8.2.2.10. Axle bores of opposite wheels

The axle bores of wheels opposite to each other at each side of the track, and if wheels aremounted in bogies the axes of the bogie pins of the unwarped trolley and crane bridge shall havean alignment divergence in the vertical plane, less than 0,15 %, maximum 2 mm of the wheelcentre distance .

Figure 8.2.2.10.



8 - 8

8.2.2.11. Bushed wheels

The centre planes of wheels rolling on a common rail must not diverge more than ± 1 mm fromthe rail axis .

Center of wheel Center of wheel

Center axis of the rail head

Figure 8.2.2.11.

For bushed wheels the above tolerances apply with the wheel in a central position between thecontact surfaces at either side of the wheel.

8.2.2.12. Guide rollers

If horizontal guide rollers are used, the centre of the distance between guide rollers at one cornermust not deviate more than ± 1 mm from the axis of the rail .

Center of distance betweenguide rollers

Center axis of the rail head

Distancebetweenguiderollers

Figure 8.2.2.12.

8.2.2.13. Bushed wheels diameter

The diameter tolerance of the wheels should correspond to the ISO tolerance classification h9. Ifrunner wheel speeds are synchronized by an "electrical shaft", tighter tolerances may berequired. These will have to be determined from case to case. These tolerances will apply alsoto non driven wheels, as the wheels must be interchangeable.



8 - 9

8.2.3. TOLERANCES FOR CRANE TRACKS

The tolerances specified below apply to new crane tracks. If in the course of use, thesetolerances are exceeded by 20 %, the track must be realigned. If the travelling behaviour isnoticeably deteriorating, it may be necessary to realign the track, even if the tolerance excess hasnot reached 20 %.

1 - The greatest divergence ∆s from the spans s is :

for s ≤ 15 m : ∆s = ± 3 mm

for s > 15 m : ∆s = ± [ 3 + 0,25 . ( s-15 ) ] mm (max. ± 25 mm)(s is to be expressed in m) (see figure 8.2.2.1.).

If horizontal guide rollers are provided on one rail only, the tolerances for the other rail onlymay be increased to three times the above values, but must not exceed 25 mm.

2 - It is assumed that with the trolley positioned in the centre of the span the deflection of bothrail tracks is approximately equal.

3 - The greatest permissible tolerance of the upper edge of the rail is ± 10 mm from thetheoretical height position. The theoretical height is either the horizontal position, or ifapplicable, the theoretical camber curve. The height position of the two rails may show adivergence of 10 mm. The curvature in a longitudinal direction may, at each point of ameasured length of 2 m, not exceed a rise of ± 2 mm.

4 - The inclination of the rail rolling surface must not exceed the following values as comparedwith the theoretical position :

Longitudinally : 0,3 %Laterally : 0,3 %

Figure 8.2.3.a.



8 - 10

5 - The maximum permissible lateral deviation of each rail in a horizontal plane is ± 10 mm.The curvature in the longitudinal axis at any point shall not exceed ± 1 mm in a length of 2 m.

Random sampling

Figure 8.2.3.b.

For cranes guided on both sides by horizontal rollers, the above values are valid also for therail surfaces of the horizontal rollers.

For cranes guided on one rail only, the requirement for the straightness of the non guidingrail can be lowered, in agreement with manufacturer.

6 - No account has to be taken of misalignment at the rail joints. It is recommended thatwelded rail joints are used.



8 - 11

.

APPENDIX

A - 8.1.3. - TEST LOADS FOR CRANES IN SOME EUROPEAN COUNTRIES

Country Dynamic tests Static tests CommentsAUSTRIA 125 % up to 25 t

110 % over 25 tBELGIUM Up to 20 t 125 %

From 20 to 50 t + 5 tOver 50 t 110 %

25 t 140 %25 to 50 t 10 t50 t 120 %

SWITZERLAND According toDIN 15030

GERMANY Pk = 1,25 . P (H1 and H2)Pg = 1,33 . P (H1 and H2)Pk = 1,25 . PPk = 1,25 . P1 + 0,25 . P0

Pg = 1,50 . P (H3 and H4)Pg = 1,33 . P - 1,4 . P

DIN 15018 part 1DIN 15019 part 1DIN 15030

FRANCE 120 %(excluding builder's tower cranesand some dismountableappliances : 110 %)

150 %(excluding builder's tower cranesand some dismountableappliances : 133 %)

GREAT BRITAIN 125 % of the SWL

ITALY 128 % self propelled cranes120 % tower cranes110 % other lifting appliances

During 15 min.

NETHERLANDS Up to 20 t 125 %From 20 to 50 t + 5 t

Not compulsory

NORWAY Up to 20 t 125 %From 20 to 50 t + 5 tOver 50 t 110 %

or FEM

FEM

SWEDEN Up to 5 t 125 %From 5 to 20 t 120 %From 20 to 50 t 115 %Over 50 t 110 %




SECTION I


F.E.M.

1.001 3rd EDITION

REVISED 1998.10.01


HOISTING APPLIANCES

B O O K L E T 9

SUPPLEMENTS AND COMMENTS TO BOOKLETS 1 to 8

The total 3rd Edition revised comprises booklets 1 to 5 and 7 to 9Copyright by FEM Section I Also available in French and German



9 -1

Booklet 9

SUPPLEMENTS AND COMMENTS

TO BOOKLETS 1 TO 8

9.1. PREFACE..............................................................................................................................................3

9.2. PRESENTATION..................................................................................................................................3

9.3. VALUES OF THE DYNAMIC COEFFICIENT ψψψψ (2.2.2.1.1.) ..............................................................4

9.4. FORCE DUE TO HORIZONTAL MOTIONS SH (2.2.3.)....................................................................69.4.1. Transverse action due to rolling action........................................................................................ 6

9.4.1.1. Model of appliance................................................................................................................. 69.4.1.2. Relationship between tangential forces and displacements.................................................... 89.4.1.3. Forces due to skewing ........................................................................................................... 99.4.1.4. Tangential forces, Fx and Fy ................................................................................................ 109.4.1.5. Skewing angle α .................................................................................................................. 11

9.4.2. Buffer effects on the structure ................................................................................................. 11

9.5. WIND ACTION (2.2.4.1.)...................................................................................................................12

9.6. QUALITY OF STEEL (3.1.3.) ............................................................................................................13

9.7. STRUCTURAL MEMBERS OTHER THAN JOINTS - PERMISSIBLE STRESSES (3.2.2.1.)....18

9.8. JOINTS MADE WITH TENSION BOLTS WITH CONTROLLED TIGHTENING (3.2.2.2.1.) .......20

9.9. CHECKING MEMBERS SUBJECT TO CRIPPLING (3.3) ..............................................................20

9.10. CHECKING MEMBERS SUBJECT TO BUCKLING (3.4).............................................................21

9.11. CASE OF STRUCTURES SUBJECTED TO SIGNIFICANT DEFORMATION (3.5.)...................229.11.1. Non-proportional effect on the structure due to the forces .................................................... 229.11.2. Non linear structures and favourable effects of own weight................................................. 24

9.12. CHOICE OF RAIL WHEELS (4.2.4.)..............................................................................................26

9.13. DESIGN OF GEARS (4.2.5.) ...........................................................................................................27



9 -2

9.14. DETERMINATION OF PERMISSIBLE STRESSES IN MECHANISM COMPONENTSSUBJECTED TO FATIGUE ( 2.1.4.3., 4.1.3.5., 4.1.3.6., 4.1.3.7.) .......................................................27

9.14.1. Introduction .............................................................................................................................. 279.14.2. Partial modifications of booklet 2 and 4.................................................................................... 289.14.3. Checking for fatigue of a mechanical component - example................................................... 34

9.15. STABILITY AND SAFETY AGAINST MOVEMENT BY WIND (Booklet 6 : deleted)................369.15.1. Scope....................................................................................................................................... 369.15.2. Stability - Calculations.............................................................................................................. 36

9.15.2.1. Stability .............................................................................................................................. 369.15.2.2. Calculations ....................................................................................................................... 369.15.2.3. travel effect ........................................................................................................................ 369.15.2.4. site effect ........................................................................................................................... 369.15.2.5. attachments effect ............................................................................................................. 369.15.2.6. collision effect .................................................................................................................... 369.15.2.7. For tower cranes ................................................................................................................ 37

9.15.3. Backward stability in service conditions ................................................................................. 389.15.4. Application of wind loads ........................................................................................................ 38

9.15.4.1. On-service.......................................................................................................................... 389.15.4.2. Out-of-service..................................................................................................................... 38

9.15.5. Crane base .............................................................................................................................. 389.15.6. Temporary additional stability devices..................................................................................... 399.15.7. Deformation.............................................................................................................................. 399.15.8. Resistance to drifting caused by wind.................................................................................... 39

9.16. TESTS (8.1.) ....................................................................................................................................41

9.17. TORANCES OF CRANES AND TRACKS (8.2.) ...........................................................................42



9 -3

9.1. PREFACE

The Rules for the Design of Hoisting Appliances established by the Technical Committee ofSection I of the Fédération Européenne de la manutention (F.E.M), which were published in theform of 8 booklets, have been increasing widely used in many countries all over the world.

However, these rules were elaborated at the beginning of the eighties and must advance to keeppace with the improving state of knowledge and the increasingly efficient conception tool beingused.

The need for a revision is based on several observations :

• The harmonized standard EN 13001 from the work of CEN/TC147/WG2 will be appliedprogressively only at the beginning of the 21st century.

Thus, it is not desirable to await this date and continue to refer to the FEM rules, certain

parts of which became obsolete. • FEM 1.001 consolidates a great deal of experience and serves manufacturers and

customers often as a basis for calculations. • Development of the rules should make future application of the harmonized standards

easier, based on methods with limit states, among others.

The text below shall be considered as a supplement to those texts which are the subject ofbooklets 2, 3, 4 and 8. Booklet 6 is deleted.

9.2. PRESENTATION

At the begining of each clause, there is a reference to the clause coming from booklet 2, 3, 4, 6 or8 that the new text may replace.

Example :

Clause 2.2.2.1.1.of booklet 2 may be replaced by the following text:



9 -4

9.3. VALUES OF THE DYNAMIC COEFFICIENT ψψψψ (2.2.2.1.1.)


For the coefficient ψ given by the clause 2.2.2.1.1 of booklet 2, we can take the value φ2 given bythe following text :

In the case of hoisting an unrestrained grounded load, the dynamic effects of transferring theload from the ground to the crane shall be taken into account by multiplying the gravitational forcedue to the mass of the hoist load by a factor φ2 (see figure F.9.3).

The mass of the hoist load includes the masses of the payload, lifting attachments and a portionof the suspended hoist ropes or chains, etc.

Figure F.9.3 - Factor φφφφ2

The factor φ2 shall be obtained as follows :

φ2 = φ 2min + β2νh

φ 2min and β2 are given in table T.9.3.a for the appropriate hoisting class. For the purpose of thisstandard, cranes are assigned to hoisting classes HC1 to HC4 according to their dynamiccharacteristics. (The selection of hoisting classes depends on the particular types of cranes andis dealt with in the European Standards for specific crane types.) Equally, values for φ2 can bedetermined by experiments or by analysis without reference to hoisting class.

νh is the steady hoisting speed, related to the lifting attachment. Values of νh are given in tableT.9.3.b.



9 -5

Table T.9.3.a - Values of ββββ2 and φφφφ 2min

Hoisting classof the appliance

β2

s/mφ 2 min.

HC1 0,17 1,05

HC2 0,34 1,10

HC3 0,51 1,15

HC4 0,68 1,20

Table T.9.3.b - Values of ννννh for estimation of φφφφ2

Load combination Type of hoist drive and its operation method of operation

HD1 HD2 HD3 HD4 HD5

Case I, Case II νh,max νh,CS νh,CS 0,5 . νh,max νh. = 0

Case III - νh,max - νh,max 0,5 . νh,max

Where :

HD1 hoist drive cannot be operated with creep speed;

HD2 a steady creep speed for the hoist drive can be selected by the crane driver;

HD3 hoist drive control system ensures the use of a steady creep speed until the load islifted from the ground;

HD4 a stepless variable speed control can be operated by the crane driver;

HD5 after prestressing the hoist medium, a stepless variable speed control is provided bythe drive control system independent of the crane driver;

νh,max. is the maximum steady hoisting speed;

νh,CS is the steady hoisting creep speed.



9 -6

9.4. FORCE DUE TO HORIZONTAL MOTIONS SH (2.2.3.)

Clause 2.2.3.of booklet 2 may be replaced by the following text:

9.4.1. Transverse action due to rolling action

Example of a method for analysing forces due to skewing.

9.4.1.1. Model of appliance

To enable an estimation to be made of the tangential forces between wheels and rails and alsoof the forces between the acting guide means that are caused by skewing of the lifting appliance,a simple travel-mechanics model is necessary. The lifting appliance is considered to betravelling at a constant speed without anti-skewing control.

The model consists of n pairs of wheels in line, of which p pairs are coupled. An individual (i)pair of wheels can be defined, either as coupled (C) mechanically or electrically, or mountedindependently (l) of each other. The latter condition is also valid in the case of independentsingle drives.

The wheels are arranged in ideal geometric positions in a rigid crane structure which istravelling on a rigid track. Differences in wheel diameters are neglected in this model. They areeither fixed (F) or movable (M) in respect of lateral movement. The lateral degree of freedom can,for example, be provided by a hinged leg.

The different combinations of transversally in-line wheel pairs that are possible are shown infigure F.9.4.a.

Coupled (C) Independent (I)

Fixed/Fixed(F/F)

CFF

IFF

Fixed/Movable(F/M)

CFM

IFM

Figure F.9.4.a - Different combinations of wheel pairs



9 -7

In figure F.9.4.b the positions of the wheel pairs relative to the position of the guide means infront of the travelling crane are defined by the distance di.

NOTE: Where flanged wheels are used instead of an external guide means, d1 = 0.



9 -8

It is assumed that the gravitational forces due to the masses of the loaded appliance (mg) areacting at a distance µl from rail 1 and are distributed equally to the n wheels at each side of thecrane runway.

Width of the rail headSl ac k of theguide

T ravell ing di rect ion

Span

Rail 1 Rai l 2

Wheel pair 1

Wheel pair 2

Wheel pair i

Wheel pair n

Figure F.9.4.b - Positions of wheel pairs

9.4.1.2. Relationship between tangential forces and displacements

It is at first necessary to assume a relationship between the tangential forces and thecorresponding displacements occurring between wheel and rail. Since the wheel has to transferdrive moments (My) to the rail and its movement is restricted by the system (crane and runway), itslides in the longitudinal and lateral directions [u(ux,uy)]; corresponding tangential forces (Fx, Fy)react on the crane (see figure F.9.4.c).

Sliding distance

Rolling distance

Geometry

Forces

Figure F.9.4.c - Tangential forces and displacements



9 -9

In general, a relationship exists between the sliding distances (ux,uy), the free-rolling distance rψ,the wheel load Fz and the tangential forces (Fx, Fy), as follows :

Fx = fx(sx, sy, pc, surface conditions) ⋅ Fz Fy = fy(sx, sy, pc, surface conditions) ⋅Fz

The friction coefficients of the rolling wheel (fx, fy) depend on the slip, i.e. the relation betweenslide and free-rolling distances (sx = ux / rψ, sy = uY / rψ), on the contact pressure between wheeland rail (pc) and on the surface conditions of the rail. To simplify the calculation, the followingempirical relationships may be used :

fx = 0,3⋅ ( )1 e

250. s−

−

x , for sx Û 0,015 fy = 0,3⋅( )

1 e250. s

−−

y , for sy Û 0,015

9.4.1.3. Forces due to skewing

The crane model is assumed to be travelling in steady motion and to have skewed to an angle α,as shown in figure F.9.4.d. The appliance may be guided horizontally by external means or bywheel flanges.

Figure F.9.4.d - Forces acting on crane in skewed position

Direction of motion Direction of rail

Lateral slip

Guide means

InstantaneousSlide pole

Rail 2Rail 1



9 -10

A guide force Fy is in balance with the tangential wheel forces Fx1i, Fy1i, Fx2i, Fy2i, which arecaused by rotation of the appliance about the instantaneous slide pole. With the maximumlateral slip sy = α at the guide means and a linear distribution of the lateral slip syi between theguide means and the instantaneous slide pole, the corresponding skewing forces can becalculated as follows :

a) Distance between instantaneous slide pole and guide means h

For systems F/F, h = (pµµ'l2 + Σd2i) / Σdi

For systems F/M, h = (pµl2 + Σd2i) / Σdi

where :

p is the number of pairs of coupled wheels;

µ is the distance of the instantaneous slide pole from rail 1;

µ' is the distance of the instantaneous slide pole from rail 2;

l is the span of the appliance;

di is the distance of wheel pair i from the close-fitting guide means. b) guide force Fy

Fy = ν f mg

where :

ν = 1 - Σdi /nh, for systems F/F

= µ' (1 - Σdi /nh), for systems F/M

f = 0,3·(1 - e-250 α) where α < 0,015 rad;

mg is the gravitational force due to the mass of the loaded appliance;

n is the number of wheels at each side of the crane runway.

9.4.1.4. Tangential forces, Fx and Fy

Fx1i = ξ1i fmg

Fx2i = ξ2i fmg

FY1i = ν1i fmg

FY2i = ν2i fmg

Where :

f and mg are as given in clause 9.4.1.3.b)

ξ1i, ξ2i, ν1i and ν2i are as given in table T.9.4.



9 -11

Table T.9.4 - Values of ξξξξ1i, ξξξξ2i, νννν1i and νννν2i

Combinationsof wheel pairs

(see figure F.9.4.a)ξ1i = ξ2i ν1i ν2i

CFF µµ'l/nhµ

n

d

hi( )1−

IFF 0 µ'( )

n

d

hi1−

CFM µµ'l/nh 0

IFM 0

9.4.1.5. Skewing angle αααα

The skewing angle α , which should not exceed 0,015 radians, shall be chosen taking intoaccount the space between the guide means and the rail as well as reasonable dimensionalvariation and wear of the appliance wheels and the rails as follows :

α = αg + αw + αt

Where :

αg = sg/wb is the part of the skewing angle due to the slack of the guide;

s g is the slack of the guide;

wb is the distance between the guide means;

αw = 0,1 (b/wb) is the part of the skewing angle due to wear;

b is the width of the rail head;

αt = 0,001 rad is the part of the skewing angle due to tolerances.

9.4.2. Buffer effects on the structure

In clause 2.2.3.4.1 replace 0,7 m/s with 0,4 m/s



9 -12

9.5. WIND ACTION (2.2.4.1.)

Clause 2.2.4.1.of booklet 2 may be replaced by the following text:

Other recommendations or work results can also be used provided that the same level of safetyis obtained



9 -13

9.6. QUALITY OF STEEL (3.1.3.)

Clause 3.1.3 of booklet 3 may be replaced by the following text:

The properties of the steel grades frequently used are provided in the following standards :

EN 10025 Hot-rolled products of non-alloy structural steels. Technical delivery conditions;

EN 10113-1 Hot-rolled products in weldable fine grain structural steels -Part 1: General delivery conditions;

EN 10137-1 Plates and wide flats made of high yield strength structural steels in the quenchedand tempered or precipitation hardened conditions - Part 1: General deliveryconditions;

EN 10149-1 Hot-rolled flat products made of high yield strength steels for cold forming - Part 1:General delivery conditions;

EN 10210-1 Hot finished structural hollow sections of non-alloy and fine grain structural steels -Part 1: Technical delivery requirements;

EN 10219-1 Cold formed welded structural hollow sections of non-alloy and fine grain steels -Part 1: Technical delivery requirements.

The quality of steels in these design rules refers to the property of the steel to exhibit ductilebehaviour at determined temperatures.

The steels are divided into four quality groups. The group in which the steel is classified, isobtained from its notch ductility in a given test and at a given temperature.

Tables T.9.6.a, T.9.6.b, T.9.6.c and T.9.6.d comprises the notch ductility values and testtemperatures for the four quality groups.

The indicated notch ductilities are minimum values, being the mean values from three tests,longitudinal test pieces are used.

The notch ductility shall be determined in accordance with V-notch impact tests according to theEuropean Standard EN 10045-1.

Steels of different quality groups can be welded together.

Tc is the test temperature for the V-notch impact test.

T is the temperature at the erection site of the crane.

Tc and T are not directly comparable as the V-notch impact test imposes a moreunfavourable condition than the loading on the crane in or out of service.



9 -14

Table T.9.6.a - Quality groups

Quality Impactenergy

Testtemperature

Steels, corresponding to the quality groupDesignation of steels

Old New

groupaccording toEN 10045-1

JTc °C

According toold standard

According toEN 10027-1 &ECISS IC 10

Accordingto

EN 10027-2

standard standard

ST 37-2ST 44-2

S235JRS275JR

1.00371.0044

DIN 17100

1 - - 50 B S355JR 1.0045 BS 4360 (1972)

Fe 360-BFe 430-BFe 510-B

S235JRS275JRS355JR

1.00371.00441.0045

EN 10025(1990)

R St 37-2St 44-2

S235JRG2S275JR

1.00381.0044

DIN 17100

2 27 + 20 E 24(A37)-2E 28 - 2

E 36 (A52)-2

S235JRS275JRS355JR

1.00371.00441.0045

NF A 35-501

40 B43 B

S235JRG2S275JR

1.00381.0044

BS 4360(1972)

Fe 360-CFe 430-CFe 510-C

S235JOS275JOS355JO

1.01141.01431.0553

EN 10025(1990)

St 37-3USt 44-3UST 52-3U

S235JOS275JOS355JO

1.01141.01431.0553

DIN 17100

3 27 ± 0 E 24 (A37)-3E 28 - 3

E 36 (A52)-3

S235JOS275JOS355JO

1.01141.01431.0553

NF A 35-501

40 C43 C50 C

S235JOS275JOS355JO

1.01141.01431.0553

BS 4360(1972)

EN 10025

(1993)

27

Fe 360-D1Fe 360-D2Fe 430-D1Fe 430-D2Fe 510-D1Fe 510-D2

S235J2G3S235J2G4S275J2G3S275J2G4S355J2G3S355J2G4

1.01161.01171.01441.01451.05701.0577

EN 10025(1990)

40

Fe 510-DD1Fe 510-DD2

S355K2G3S355K2G4

1.05951.0596

4

27

- 20 St 37-3N-

St 44-3N-

St 52-3N-

S235J2G3S235J2G4S275J2G3S275J2G4S355J2G3S355J2G4

1.01161.01171.01441.01451.05701.0577

DIN 17100

40 --

S355K2G3S355K2G4

1.05951.0596

27 E 24 (A37)-4E 28 - 4

S235J2G3S275J2G3

1.01161.0144

NF A 35-501

40 E 36 (A52)-4 S355K2G3 1.0595

27

40 D43 D50 D

S235J2G3S275J2G3S355J2G3

1.01161.01441.0570

BS 4360(1972)

St 52-3N S355J2H 1.0576 DIN 17100 EN 10210-1

50D S355J2H 1.0576 BS 4360(1972)

(1994)



9 -15

Table T.9.6.b - Quality groups


Testtemperature


Old New

groupaccording toEN 10 045-1

J

Tc °CAccording toold standard


Accordingto

EN 10027-2standard standard

4047

S275NS275NL

1.04901.0491

4047

E 355 RE 355 FP

S355NS355NL

1.05451.0546

4047

E 420 RE 420 FR

S420NS420NL

1.89021.8912

NF A 36-201(1984)

EN 10113-2(1993)

4047

E 460 RE 460 FP

S460NS460NL

1.89011.8903

4047

StE285TStE285

S275NS275NL

1.04901.0491

4047

StE355TStE355

S355NS355NL

1.05451.0546

4047

StE420TStE420

S420NS420NL

1.89021.8912

DIN 17102(1983)

EN 10113-2(1993)

4 4047

- 20 StE460TStE460

S460NS460NL

1.89011.8903

4047

40EES275NS275NL

1.04901.0491

4047

50EES355NS355NL

1.05451.0546

4047

S420NS420NL

1.89021.8912

(UnitedKingdom)

EN 10113-2(1993)

4047

55EES460NS460NL

1.89011.8903

4047

S275MS275ML

1.88181.8819

4047

S355MS355ML

1.88231.8834

4047

S420MS420ML

1.88251.8836

EN 10 113-3(1993)

4047

S460MS460ML

1.88271.8838



9 -16

Table T.9.6.c - Quality groups


Testtemperature


Old New

groupaccording to EN

10045-1

J

Tc °CAccording toold standard


Accordingto

EN 10027-2norme norme

304050

S 460 TS460Q

S460QLS460QL1

1.89081.89061.8916

304050

S 500 TS500Q

S500QLS500QL1

1.89241.89091.8984

304050

S 550 TS550Q

S550QLS550QL1

1.89041.89261.8986

304050

S 620 TS620Q

S620QLS620QL1

1.89141.89271.8987

NFA 36-204(1992)

EN 10137-2(1995)

304050

S 690 TS690Q

S690QLS690QL1

1.89311.89281.8988

304050

S890QS890QLS890QL1

1.89401.89831.8925

3040 S 960 T

S960QS960QL

1.89411.8933

4

304050 -20

TStE 460 VS460Q

S460QLS460QL1

1.89081.89061.8916

304050

StE 500 VTStE 500 VEStE 500 V

S500QS500QLS500QL1

1.89241.89091.8984

304050


S550QS550QLS550QL1

1.89041.89261.8986

304050


S620QS620QLS620QL1

1.89141.89271.8987

(Allemagne) EN 10137-2(1995)

304050


S690QS690QLS690QL1

1.89311.89281.8988

304050

TStE 890 VEStE 890 V

S890QS890QLS890QL1

1.89401.89831.8925

3040 TStE 960 V

S960QS960QL

1.89411.8933

4050

S500AS500AL

1.89801.8990

4050

S550AS550AL

1.89911.8992

4050

S620AS620AL

1.89931.8994

EN 10137-3(1995)

4050

S690AS690AL

1.89951.8996



9 -17

Table T.9.6.d - Quality groups

ality Impactenergy

Testtemperature


Old New

oupaccording toEN 10 045-1

J

Tc °CAccording to old

standardAccording toEN 10027-1 &ECISS IC 10

Accordingto

EN 10027-2standard standard

E 315 D S315MC 1.0972

E 355 D S355MC 1.0976

E 420 D S420MC 1.0980

S460MC 1.0982

S500MC 1.0984 NF A 36-231

E 560 D S550MC 1.0986 (1992)

S600MC 1.8969

S650MC 1.8976

E 690 D S700MC 1.8974

QStE 300 TM S315MC 1.0972

QStE 360 TM S355MC 1.0976

QStE 420 TM S420MC 1.0980

QStE 460 TM S460MC 1.0982

QStE 500 TM S500MC 1.0984 SEW 092 EN 10149-2

QStE 550 TM S550MC 1.0986 (1995)

QStE 600 TM S600MC 1.8969

QStE 650 TM S650MC 1.8976

4 40 - 20 QStE 690 TM S700MC 1.8974

43F35 S315MC 1.0972

46F40 S355MC 1.0976

50F45 S420MC 1.0980

S460MC 1.0982 (United

S500MC 1.0984 Kingdom)

60F55 S550MC 1.0986

S600MC 1.8969

S650MC 1.8976

75F70 S700MC 1.8974

QStE 260 N S260NC 1.0971

QStE 300 N S315NC 1.0973 SEW 92-75

QStE 360 N S355NC 1.0977

QStE 420 N S420NC 1.0981 EN 10149-3

S260NC 1.0971 (1995)

40/30 S315NC 1.0973 (United

43/35 S355NC 1.0977 Kingdom)

S420NC 1.0981



9 -18

9.7. STRUCTURAL MEMBERS OTHER THAN JOINTS - PERMISSIBLESTRESSES (3.2.2.1.)Clause 3.2.1.1.of booklet 3 may be replaced by the following text:

Table T.9.7.a - Values for fy, fu, and σσσσa for non alloy, fine grain structural steelsand such in the quenched and tempered conditions

Standard Steel Thickness Yield Ultimate Permissible stresses: σa

t stress fy stress fu Case I Case II Case IIImm N/mm2 N/mm2 N/mm2 N/mm2 N/mm2

S235 ≤ 16 235 340 157 177 214(Fe360) ≤ 40 225 340 150 169 205

EN 10025 ≤ 100 215 340 143 162 195≤ 150 195 340 130 147 177≤ 200 185 320 123 139 168≤ 250 175 320 117 132 159

S275 ≤ 16 275 410 183 207 250(Fe440) ≤ 40 265 410 177 199 241

≤ 63 255 410 170 192 232≤ 80 245 410 163 184 223≤ 100 235 410 157 177 214≤ 150 225 400 150 169 205≤ 200 215 380 143 162 195≤ 250 205 380 137 154 186

EN 10025 S355 ≤ 16 355 490 237 267 323and (Fe510) ≤ 40 345 490 230 259 314

EN 10113 S355N ≤ 63 335 490 223 252 305and ≤ 80 325 490 217 244 295

S355NL ≤ 100 315 490 210 237 286steels up ≤ 150 295 470 197 222 268to t ≤150 ≤ 200 285 450 190 214 259

≤ 250 275 450 183 207 250

EN 10113 S460 ≤ 16 460 550 307 346 418≤ 40 440 550 293 331 400≤ 63 430 550 287 323 391≤ 80 410 550 273 308 373≤ 100 400 550 267 301 364

EN 10137 S460 ≤ 50 460 550 307 346 418≤ 100 440 550 293 331 400≤ 150 400 500 267 301 364

S690 ≤ 50 690 770 460 519 627≤ 100 650 760 433 489 591≤ 150 630 710 420 474 573

S890 ≤ 50 890 940 593 669 809≤ 100 830 880 553 624 755

S960 ≤ 50 960 980 640 722 873



9 -19

NOTE 1: The yield stress fy and the permissible stress σa of the hot finished structural

hollow sections according to EN 10210-1 comply with those in Table T.9.7, t ≤ 65 mm, forgrades 235 to 460.

NOTE 2: The yield stress fy and the permissible stress σa of the cold formed welded

structural hollow sections according to EN 10219-1 comply with those in Table T.9.7, t ≤ 40mm, for grades 235 to 460.

Table T.9.7.b - Values for fy, fu, and σσσσa for high yield strength steels forcold forming and hollow sections

Standard Steel Thickness Yield Ultimate Permissible stresses: σa

t stress fy stress fu Case I Case II Case IIImm N/mm2 N/mm2 N/mm2 N/mm2 N/mm2

S315 315 390 210 237 286S355 355 430 237 267 323

EN 10149 S420 420 480 280 316 382S460 all t 460 520 307 346 418S500 500 550 333 376 455S550 550 600 367 414 500S600 600 650 400 451 545S650 ≤ 8 650 700 433 489 591

> 8 630 700 420 474 573S700 ≤ 8 700 750 467 526 636

> 8 680 750 453 511 618

EN 10219-1 S420MH ≤ 16 420 500 280 315 382and MLH ≤ 40 400 500 267 300 363



9 -20

9.8. JOINTS MADE WITH TENSION BOLTS WITH CONTROLLEDTIGHTENING (3.2.2.2.1.)


For the calculation developed in clause 3.2.2.2.1, other recommendations or standards (forexample : VDI 2230, FDE 25030, or the work of CEN/TC 185/WG 7) can be used.

However, different methods may not be mixed.

Tests (for example : extensometric) can complete and/or replace the calculations.

9.9. CHECKING MEMBERS SUBJECT TO CRIPPLING (3.3)

Clause 3.3.of booklet 3 may be replaced by the following text:

The method presented in ENV 1993-1 :1992 Eurocode 3 :Design of steel structures Part 1.1 may be used.



9 -21

9.10. CHECKING MEMBERS SUBJECT TO BUCKLING (3.4)

Clause 3.4 of booklet 3 may be replaced by the following text:

In determining the buckling safety coefficients, stated below, it was considered that flat platesunder compressive stresses equally distributed over the plate width, are exposed to a greaterdanger of buckling than plates under stresses changing from compression to tension over theplate width.

In consequence, safety against buckling was made dependent on the ratio ψ of stresses at theplate edges (appendix A-3.4. of booklet 3).

It shall be verified that the calculated stress is not higher than the critical buckling stress dividedby the following coefficients ηv given by table T.9.10:

Table T.9.10

Case Buckling safety ηv

Buckling of plane membersIIIIII

1,70 + 0,175 (ψ - 1)

1,50 + 0,125 (ψ - 1)

1,35 + 0,075 (ψ - 1)Buckling of curved members :

Circular cylinders(e.g. tubes)

IIIIII

1,701,501,35

The edge-stresses ratio ψ varies between + 1 and - 1.

Appendix A.3.4.of booklet 3 gives the procedure for determining the critical buckling stress.

Checking members subjected to buckling can be carried out according to otherrecommendations , for example ENV 1993-1.

ENV 1993-1 is based on limit state analysis : partial safety factors γF and γM are used.



9 -22

9.11. CASE OF STRUCTURES SUBJECTED TO SIGNIFICANTDEFORMATION (3.5.)


9.11.1. Non-proportional effect on the structure due to the forces

Figure F.9.11.a

In this case the stresses in the members cannot beproportional to the forces which cause them due to thedeformation of the structure as a result of the application ofthese forces.

This is the case, for example, with the stresses produced inthe column of a crane (illustrated in figure F.9.11.a) where it isclear that the moment in the column is not proportional to theforces applied because of deformations that increase theirmoment arm.

In this case the calculation can be carried out :- either by using the limit states method;- or by using the method described in clause 3.5 of booklet 3.

Limit states method

The figure F.9.11.b shows the limit states method :

Figure F.9.11.b - Typical flow chart of the limit state method

fi is the load i on the element or component;

Fj is the load combination j from loads fi, multiplied by partial load coefficients and riskcoefficient, when applicable;

Sk are the load effects in section k of members or supporting parts, such as inner forces andmoments, resulting from load combination Fj;

σ1l are the stresses in the particular element l as a result of load effects Sk;

σ2l are the stresses in the particular element l arising from local effects;

σl is the resulting design stress in the particular element l;

R is the specified strength or characteristic resistance of the material, particular element orconnection, such as the stress corresponding to the yield point, limit of elastic stability orfatigue strength (limit states);



9 -23

lim σ is the limit design stress;

γP are the partial load coefficients applied to individual loads according to the loadcombination under consideration;

γn is the risk coefficient, where applicable;

γm is the resistance coefficient.

NOTE 1: Instead of a comparison of stresses, as mentioned above, a comparison offorces, moments, deflections, ets. may be made.

NOTE 2: A general description of the limit state, method of design is given in ISO 2394 :1986, General principle on reliability for structures.

The individual specific fi loads are calculated according to the data in booklet 2.

They are multiplied by the appropriate partial coefficients of load.

Then they are combined according to the combinations given in clause 2.3 ofbooklet 2.

Table T.9.11 - Partial coefficients γγγγp

Loads Clause Loading condition

(see 2.3)

Case I Case II Case III

Dead unfavourable effect 2.2.1 1,22 1,16 1,10

loads Favourable effect - estimatedweight

0,90 0,95 1,00

Favourable effect - measuredweight

1,00 1,00 1,00

Working loads 2.2.2.1 1,34 1,22

Acceleration from drives 2.2.3 1,34 1,22 1,10

Effects of climate 2.2.4 1,16 1,10

with γm = 1,10



9 -24

For checking erection or dismanling, the case III is appropriate.

NOTE: The values given in table 10 of the document pr EN 13001-2 may be accepted.

9.11.2. Non linear structures and favourable effects of own weight

Clause 3.5 of Booklet 3 describes a corrective method for proof of competence calculations incases of structures subjected to significant deformation. However, the significant deformationsare not the only cases where the designer shall consider the use of similar correction.

By combining clauses 2.3.1 and 3.2.1 or 3.4 the conditions for calculated stress in loadcombination Case I can be expressed as follows:

σ γc (SG + ψ SL + SH) ≤ σcr / νwhere

σcr is the yield stress, crippling stress or buckling stress, whichever is the most critical one,

ν is the relevant coefficient νE or νV.

The above formula can also be presented as:

νσγc (SG + ψSL + SH) ≤ σcr

for any structural system.

If the structural system is behaving nearly linearly, the above formula can be modified as follows:

σ = kg ν γc SG + kL ν γc ψ SL + kh ν γc SH ≤ σcr

where coefficients kg, kL, and kh represent the linear relationships between the load effects (SG,SL, SH) and the calculated stress. Those coefficients depend on the configuration and type ofloading of the crane.



9 -25

A simplified example: A simply supported beam,with span l and section modulus W, loaded byits own weight mg (SG ) and in the middle by force F (produced by the load effects SL) . Thebending stress is calculated by the formula:

σν γ ν γ ψ

=⋅ ⋅ ⋅

⋅+

⋅ ⋅ ⋅ ⋅

⋅c cmg l

W

F l

W8 4

where it is seen that kl

Wg = ⋅8and k

l

WL =⋅4

In order to check the most critical effect of all the loads for a particular design detail, it is evidentthat the signs for the variable loads shall be selected so that they lead to the maximumcombined stress (if such a combination is physically possible). Furthermore, the loads aremultiplied by coefficients taking into account dynamic effects and an adequate margin for failure.However, in a case where the dead weight SG decreases the absolute value of the stress due tothe variable loads (SG having an opposite, favourable stress effect) the multiplication of the deadweight by its coefficients would lead to an situation where the actual margin for the critical stressmight be dangerously reduced. To maintain the intended margin for failure, the calculationmethod described in clause 3.5 shall be applied in the following cases:

1. - When the dead weight has an effect in the opposite direction to the effect of the variableloads, i.e. the dead weight has a balancing effect. Examples: towers and lower structures ofslewing jib cranes and tower cranes.

2. - Especially for structures where the dead weight has an effect in the opposite direction to theeffect of the variable loads and the tension and compression forces are carried by differentstructural elements.

Example 1: Tie-downs for storm anchoring take the difference between upwards anddownwards loads while the wheels carry all the downwards loads in the case of oppositewind action.

Example 2: Bogie pins and the ties of pin joints (such as end cups). The pins carry all thecompression while the ties carry the difference between upwards and downwards loads.

3. - Pre-stressed structures.

Example: Bolted flange joints.

In this case the variable loads shall be multiplied by the coefficient ν, but the pre-stress loadsshall be taken as the lowest estimated nominal values. The coefficient for the dead weight shallbe selected between 1 and ν depending on whether its effect is favourable or unfavourable forthe bolts.



9 -26

9.12. CHOICE OF RAIL WHEELS (4.2.4.)


The method proposed in clause 4.2.4.1 can be used with the values of PL and c2 given belowtables T.9.12.a and T.9.12.b:

Table T.9.12.a - Values of PL

Ultimate strength of metalused for rail wheel

N/mm_

PL

N/mm2

Minimum strengthfor the rail

N/mm2

fu > 500 5,00 350

fu > 600 5,60 350

fu > 700 6,50 510

fu > 800 7,20 510

fu > 900 7,80 600

fu > 1000 8,50 700

Table T.9.12.b - Values of c2

Group classificationof mechanism

c2

M1 and M2 1,25

M3 and M4 1,12

M5 1,00

M6 0,90

M7 and M8 0,80

The hardening of the running surface at the depth of 0,01D may be taken into account whenselecting the value of PL

When using the tables above, it is not necessary to consider the 5 last paragraphs of clause4.2.4.1.3 in booklet 4.



9 -27

9.13. DESIGN OF GEARS (4.2.5.)


Standards or calculation methods such as follows may be used, for example:

• NF E 23015, Henriot method;• DIN 3990;• ISO 6336.

For the design calculation for gears, the coefficient γm is not cumulative with the service factor

(ka). However, it shall be at least equal to γm.

9.14. DETERMINATION OF PERMISSIBLE STRESSES IN MECHANISMCOMPONENTS SUBJECTED TO FATIGUE ( 2.1.4.3., 4.1.3.5., 4.1.3.6.,4.1.3.7.)

Clauses 2.1.4.3, 4.1.3.5, 4.1.3.6, 4.1.3.7 and appendix A 4.1.3 of booklets 2 and 4 may bereplaced by the following text:

9.14.1. Introduction

The calculation methods for determining the fatigue strength of mechanism components aresimilar in the documents of section I (FEM 1.001 edition 1987) and section II (FEM 2.131 andFEM 2.132 edition 1992)

In the above-mentioned editions, the Wöhler curve of a component includes a second slope(factor c') for the number of cycles n greater than 2.10

6 :

Figure F.9.14.a



9 -28

The presence of this second slope results in the determination of very low values for fatiguestrength for very heigh number of cycles n, and consequently the safety level is too high.

The text below proposes in particular the cancelling of the second slope of the Wöhler curve ispresented below.

9.14.2. Partial modifications of booklet 2 and 4

BOOKLET 2 MODIFIED

NOTE: The modifications are written in bold face type.

2.1.4.3 STRESS SPECTRUM

....In many applications the function f(x) may be approximated by a function consisting of acertain number r of steps, comprising respectively n1, n2,... nr stress cycles ; the stress σ may

be considered as practically constant and equal to σi during ni cycles. If n represents the total

number of cycles and σmax the greatest of the stresses σ1, σ2, ..., σr there exists a relation :

r

n1 + n2 + ... + nr = ∑ ni = n et σ1 > σ2 > ... > σri =1

we obtain an approximated form :

ksp = σ

σ1

max

c

n

n1 +

σ

σ2

max

c

n

n

2 + ..... +

σ

σr

c

max

n

nr =

σ

σi

ci

i

r n

nmax

=∑

1

the summation is truncated for the first ni ≥≥≥≥ 2.106. This ni is taken as nr and replaced withnr = 2.106 cycles.

Depending on its stress spectrum, a component is placed in one of the spectrum classesP1, P2, P3, P4, defined in table T.2.1.4.3.



9 -29

BOOKLET 4 MODIFIED


4.1.3.5 WÖHLER CURVE

In this context, the Wöhler curve, shows the number of stress cycles n which can bewithstood before fatigue failure as a function of the maximum stress σ (or τ), when all stresscycles present the same amplitude and the same ratio k between extreme values.

With regard to this WÖHLER curve, the following hypotheses are made respectively

- for n = 8.103 : σ = σR or τ = σR

3

- for 8·103 ≤ n ≤ 2·106, the area of limited endurance, the function is represented by a straight line TD in a reference comprising two logarithmic scale axes

(figure 4.1.3.5 modified).

The slope of the WÖHLER curve, in the interval considered, is characterizedby the factor :

c = tan ϕ = log log

log log

2 10 8 106 3⋅ − ⋅

−σ σR d

or c = tan ϕ = log log

log log

2 10 8 10

3

6 3⋅ − ⋅

−σ

τRd

- for n > 2.106 : σ = σd or τ =τd

Figure 4.1.3.5 modified

The spectrum factor ksp of the component is determined by means of the above mentionedvalue of c.



9 -30

4.1.3.6. FATIGUE STRENGTH OF A MECHANICAL COMPONENT

The fatigue strength σk or τk of a given mechanical component is determined by the followingexpressions respectively :

σ σk

jc

d=

⋅

−

28

or τ τk

j

cd=

⋅

−

28

where j is the component's group number.

The group classification of components, on the basis of their total number of cycles n and theirspectrum factor ksp, as well as the critical fatigue stresses associated with each group, areillustrated in figure 4.1.3.6 modified where σjk represents the stress applying to group Ej. For the

critical shear stresses, the letter σ must be replaced with τ.

Figure 4.1.3.6modified

Concerning the relation between spectrum classes P1 to P4 and the spectrum factor ksp seetable T.2.1.4.3 in booklet 2.



9 -31

Comment : The above fatigue strengths are based on the component’s group number sothose values are discontinuous. The above formulas may be usefully replaced with thefollowing:

σσ σ

kd

spd

c

d

sp

c

kn

nk

n=

⋅

=

⋅⋅

1

6

1

2 10

or ττ τ

kd

spd

c

d

sp

c

kn

nk

n=

⋅

=

⋅⋅

1

6

1

2 10

See example in 9.14.3.



9 -32

BOOKLET 4 MODIFIED


4.1.3.7 PERMISSIBLE STRESSES AND CALCULATIONS

The permissible stresses σaf and τaf are obtained by dividing the stresses σk and τk, defined in4.1.3.6., respectively by a safety factor of kν .

Taking : νkc= 3 21

,

σaf and τaf will be obtained by the relations :

σσν

af

k

k

= ττν

af

k

k

=

and it is verified that : σ σ≤ af τ τ≤ af

with : σ maximum calculated normal stress amplitude,

τ maximum calculated shear stress amplitude.In the case of components acted upon simultaneously by normal stresses and shearstresses with different ratios κ between extreme stresses, the following condition must besatisfied :

σ

σ

σ

σ

σ σ

σ σ

τ

τ νx

kx

y

ky

x y

kx ky k k

+

−

⋅

+

≤

2 2 2

2

11,

in which :σx, σy = maximum normal stresses in the directions x and y respectively,

τ = maximum shear stress,

σkx, σky = fatigue strength for normal stresses, in the directions x and y respectively,

τk = shear fatigue strength.If it is not possible to determine the most unfavourable case of the foregoing relation from thecorresponding stresses σx, σy and τ, calculations must be performed separately for the loads

σx max, σy max and τmax and the most unfavourable corresponding stresses.It should be noted that the checks described above do not guarantee safety against brittlefracture.

Such safety can be ensured only by a suitable choice of material quality.



9 -33

BOOKLET 4 MODIFIED

A- 4.1.3. - DETERMINATION OF PERMISSIBLE STRESSES IN MECHANISM COMPONENTSSUBJECTED TO FATIGUE


The endurance limit for a polished specimen is a laboratory value, which is practically neverattained in parts actually used. Numerous factors - shape, size, surface condition (machiningquality) and possible corrosion - induce discontinuities resulting in "notch effects", whichdecrease the permissible stresses in the part, when these stresses are calculated byconventional elementary methods for the strength of materials. These factors are taken intoaccount by coefficients, called ks, kd, ku, kc, respectively all greater than or equal to unity.Theendurance limit fora polished specimen isdivided by the product of theses coefficients.

Designers are advised against using a skin factor taking into account the influence ofsurface treatments....The calculation for permissible stresses for fatigue can also be constructed with thestress gradient method (or Siebel method), which takes into account plastic adaptationwith notch root ..

This method is used in the following documents :

- "Handbuch für Werkstoffprüfung", E. SIEBEL, Berlin 1958,

- "Calcul des pièces à la fatigue - Méthode du gradient", A. BRAND, CETIM 1980

- FKM Forschungskuratorium Maschinenbau e. V. (Hrsg.) : Festigkeitsnachweis. VorhabenNr. 154, FKM-Heft 183-1Frankfurt 1994,- E DIN 743 : Tragfähigkeit von Wellen und Achsen. Teile 1-4, Beuth-Verlag, Berlin, April1996



9 -34

9.14.3. Checking for fatigue of a mechanical component - example

We consider a shaft whose initial stress spectrum is as given in table T.9.14:

Table T.9.14

Level σi (N/mm_) σi/σmax ni (real) ni (effective)

1 200 1 10 000 10 000

2 160 0,8 50 000 50 000

3 125 0,625 200 000 200 000

4 90 0,45 1 500 000 1 500 000

5 80 0,4 5 000 000 2 000 000

6 71 0,355 20 000 000 0

7 63 0,315 50 000 000 0

n = ∑ni = 3 760 000

According to booklet 2 Classification of the component

n = 3,76.106

It belongs to the class of utilization B8 (clause 2.1.4.2).

c = 3 (slope of the Wöhler curve for the component)

We calculate the spectrum factor ksp (clause 2.1.4.3):

k 110

3,76 100,8

5 10

3,76 100,625

2 10

3,76 100,45

1,5 10

3,76 100,4

2 10

3,76 10sp

4

63

4

63

5

63

6

63

6

6= ⋅

⋅+ ⋅

⋅

⋅+ ⋅

⋅

⋅+ ⋅

⋅

⋅+ ⋅

⋅

⋅

= 0,0026 + 0,006809 + 0,012986 + 0,036353 + 0,034043

= 0,09285

It belongs to the spectrum class P1 and, consequently, to the component group E6 (clause2.1.4.4).



9 -35

According to booklet 4 Checking for fatigue

The endurance limit of the component is : σd = 100 N/mm2 (clause 4.1.3.4).

The fatigue strength of the shaft is (clause 4.1.3.6):

σ σk

jc

d N mm= = =−

−

2 2 100 158

8 8 63 2. . /

The safety factor is (clause 4.1.3.7): νk = 3.21/c = 3.21/3 = 1.473

The permissible stress of the shaft is : σσ

νafk

k

= = =158

14731073

,, N/mm2

The maximum calculated stress is :

σ = 200 N/mm2 σ = 200 N/mm2 > σaf = 107.3 N/mm2

The shaft is not acceptable for fatigue, because the max stress amplitude is higher than thepermissible value.

NOTE: If we use the fatigue strength formula proposed in the comment of the clause4.1.3.6, it becomes :

σσ

kd

sp

c

kn

=

⋅⋅

=

⋅

=

2 10

100

0 092853760000

2000000

178 9

6

1 1 3/ /

,

, N/mm2

The permissible stress of the shaft is :

σσ

νafk

k

= = =178 9

14731215

,

,, N/mm2

The maximum calculated stress is :

σ = 200 N/mm σ = 200 N/mm2 > σaf = 121.5 N/mm2

The shaft is still not acceptable for fatigue, because the max stress amplitude is higher than thepermissible value.



9 -36

9.15. STABILITY AND SAFETY AGAINST MOVEMENT BY WIND(Booklet 6 : deleted)

The following text replaces booklet 6

9.15.1. Scope

These requirements specifiy the conditions to be met when verifying, by calculation, the stabilityof cranes that are subject to tipping and drifting; it assumes that the cranes are standing on afirm, level supporting surface or track.

NOTE: Where the crane is required to operate on an inclined surface, the manufacturershall take the specified conditions into account.

9.15.2. Stability - Calculations

9.15.2.1. Stability

A crane is said to be stable when the algebraic sum of the stabilizing moments is greater than orequal to the sum of the overturning moments.

9.15.2.2. Calculations

Calculations shall be made to verify the stability of the crane by computing the sum of theoverturning moments and the stabilizing moments using the loads multiplied by the load factorgiven in table T.9.15.a

In all calculations, the position of the crane and its components, and the effect of all loads andforces, shall be considered in their least favourable combination, direction and effect.

9.15.2.3. travel effect

For cranes designed to travel with load, the forces induced by the maximum allowable verticaltrack variation as specified by the manufacturer shall be taken into account, in addition to otherloads specified in condition II of table T.9.15.a.

9.15.2.4. site effect

Where required, excitation effects appropriate to the particular site or zone shall be consideredas an additional loading condition.

9.15.2.5. attachments effect

In the calculations shown in table T.9.15.a, consideration shall be given to the loads induced bythe weight of the crane and its components, including any lifting attachments which are apermanent part of the crane in its working condition.

9.15.2.6. collision effect

For the case of collision (e. g. buffer impact), the stability calculations shall be based on dynamicconsiderations.



9 -37

9.15.2.7. For tower cranes

For tower cranes the stability case according to table T.9.15.b shall be met.

Table T.9.15.a.

Condition Loading Load factor tobe considered

I. Basic Stability

Loads induced by the dead weight

Applied load

Wind load

Inertia forces*

1,0

1,6P

0

0

II. Dynamic Stability


Applied load

Wind load

Inertia forces

1,0

1,35 P

1,0 W1

1,0 D

III. Backward Stability

(Sudden release of load)


Applied load

Wind load

Inertia forces

1,0

-0,2 P

1,0 W1

0

IV. ExtremeWind Loading


Applied load

Wind load

Inertia forces

1,0

1,0 P1

1,2 W2

0

V. Stability DuringErectionor dismantling


Applied load

Wind load

Inertia forces

1,0

1,25 P2

1,0 W3

1,0 D

Where :

D are the inertia forces from drives

P is the net load

P1 is the fixed load lifting attachment; out-of-service the fixed load lifting attachmentshall be considered as part of the weight of the crane and its components

P2 is the weight of the part being installed/removed during erection or dismantling

W1 is the in-service wind effect

W2 is the out-of-service wind effect - gusting effects are included

W3 is the in-service wind effect W1 or the effect of the wind limit for erection work inaccordance with the instruction handbook of the manufacturer



9 -38

Table T.9.15.b.

Condition Loading Load factor to beconsidered

VI Stability DuringErection ordismantling

see figure F.9.15.

Loads induced by the deadweight

Horizontal applied load

Vertical applied load

Wind load

Inertia forces

1,0

0,10 P2

1,16 P2

1,0 W3

1,0 D

Figure F.9.15 - Example: application of a load P2 for fitting a jib

9.15.3. Backward stability in service conditions

The backward stability is covered by condition III.

9.15.4. Application of wind loads

9.15.4.1. On-service

On-service wind forces shall always be applied in the least favourable direction.

9.15.4.2. Out-of-service

Out-of-service wind forces shall be applied in the least favourable direction for those craneswhich are not free to rotate with the wind. For those cranes which are designed to rotate with thewind, the force shall be applied on the superstructure in the direction contemplated, and in theleast favourable direction on the lower structure.

9.15.5. Crane base

The crane manufacturer shall specify the forces imposed by the crane on the ground orsupporting structure. The information given by the manufacturer should state all applicableconditions for which the forces have been stipulated (including out-of-service wind). Where thecrane base provides all or part of the stability of the crane, the manufacturer shall specify therequirement applicable to the crane base.



9 -39

9.15.6. Temporary additional stability devices

Tower cranes shall be stable in their operating configuration (condition I to IV in table T.9.15.a)without use of temporary additional devices.

Temporary additional devices may be used to satisfy condition V in table T.9.15.a, erection ordismantling.

Detachable ballast may be used to satisfy the case in condition IV of table T.9.15.a. However, thiscondition shall be met without this extra ballast, using a factor of 1,1 W2.

9.15.7. Deformation

Where it can be shown that with the most unfavourable loads for the most destabilizingconfiguration, and consideration given to deformation (Second Order Theory), the effect on theoverturning moment does not exceed 10%.Then stability calculations may be carried out ignoringdeflections (First Order Theory) for ease of calculation.

However, when this is the case, the overturning moments for each condition in table T.9.15.ashall be increased by the value obtained above according to the second order.

9.15.8. Resistance to drifting caused by wind

The resistance to drifting caused by wind shall be proven by calculation for all cranes on railsoperating in the open air under the conditions in table T.9.15.c.

Table T.9.15.c - Drifting caused by wind

Condition Loading Load factor to beconsidered

1.- IN SERVICE Loads induced by the dead weight

Applied load

Wind load

Inertia forces

1,0

1,35 P

1,2 W1

1,0 D

2.- OUT OF SERVICE Loads induced by the dead weight

Applied load

Wind load

Inertia forces

1,0

1,0 P1

1,2 W2

0



9 -40

Where rail clamps or similar measures are necessary to avoid out-of-service drifting, theoperator's manual shall advise that they shall be applied when the in-service wind limit has beenreached.

The resistance to travel due to friction and the coefficients of friction shown in table T.9.15.d shallapply.

Table T.9.15.d - Resistance to travel and coefficients of friction

Ratio : Resistance to travel / Radial load Coefficient of friction between track and

Plain bearings Anti friction bearings the braked wheel the rail clamp

0,02 0,005 0,14 0,25

NOTE: Higher coefficients of friction may be allowed for if it can be shown that these arepresent in all surface conditions and qualities (e.g. oil, dirt, ice).



9 -41

9.16. TESTS (8.1.)


Prior to being in service, appliances must be tested under overload conditions, as follows :

The cranes shall be tested dynamically, using the maximum nominal speed for each drivemovement and overload that is not less than that obtained by multiplying the rated load bycoefficient ρ given in table T.9.16:

Table T.9.16 - Values of ρρρρ dynamic test coefficient

Last (t) ψ ≤ 1,2 ψ ≤ 1,4 ψ > 1,4

≤ 30 1,2 1,25 1,3

≤ 100 1,15 1,2 1,25

< 100 1,10 1,15 1,2

NOTE: These values are not applicable for cranes equipped with powered series hoistmechanisms with a direct action lifting force limiter. In that case the values given in FEM9.751 may be used.

where ψ = dynamic coefficient according clause 9.3.

For cranes this dynamic test also covers the requirements of static overload and stability testing.



9 -42

9.17. TORANCES OF CRANES AND TRACKS (8.2.)Clause 8.2.of booklet 8 may be replaced by the following text:

The axes of the wheel bores shall not have an angular deviation greater than α from itstheoretical axis, in the horizontal plane, see figure F.9.17

The theoretical axis is the arithmetic mean value of the direction angles of all wheel axes. Thevalues for α are given in table T.9.17 below.

Theoreticalpositionof all wheels

Figure F.9.17

Table T.9.17 - Wheel direction deviation angle αααα/rad

Class of Travel speed v (m/min)

mechanism ≤25 ≤50 ≤100 ≤200 >200

M1 0.0012 0,0012 0,0012 0,0010 0,0008

M2 0,0012 0,0012 0,0010 0,0008 0,0007

M3 0,0012 0,0010 0,0008 0,0007 0,0006

M4 0,0010 0,0008 0,0007 0,0006 0,0005

M5 0,0008 0,0007 0,0006 0,0005 0,0004

M6 0,0007 0,0006 0,0005 0,0004 0,0004

M7 0,0006 0,0005 0,0004 0,0004 0,0004

M8 0,0005 0,0004 0,0004 0,0004 0,0004

NOTE: The angles α give approximately same amount of wear of the wheels and rails, when thewheels are designed according to 9.12.



Rules for the Design of Hoisting Appliances

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