Riggers Helper ™Warning: The information in this file is to be used for reference only.Consult an Engineer for any overhead work to be performed.Users of this material assume all liability for actions taken as a result of this material.

Data in this file compiled by Marty Cohen.Email maharigs@juno.com

Reference Material:Backstage Handbook Third edition by Paul Carter, Broadway PressCrosby users guide Copyright 1993 The Crosby Group, Inc.Wire Rope & Rigging Consultants, Inc. PO box 728 Vancouver, WA. 98666Safe Lifting Stage Rigging Inc. PO box 95 San Carlos, CA. 94070Handbook for Riggers W. G. Newberry 1989 EditionUS Navy Riggers Handbook

Rule of Thumb:

NailsSafe load lateral resistance in pounds equals 8 times the pennyweight1 - 6d nail == 8x 6, or 48 lbs.1 - 8d nail == 8 x 8, or 64 lbs.

Manila ropeChange rope diameter to eights of an inch; Square the numerator and multiply by 20.1/2 " rope SWL = 4/8 = 4 x 4 x 20=320lbs.

Plow steel cableSafe load in tons is 8 times the diameter in inches squared.1/2" rope ==1/2 x 1/2 == 1/4 x 8 = 2 Tons

Open eye hookSafe load in tons is diameter of eye in inches squared.2" hook, 2 x 2 =4 Tons

ShackleSafe load in tons is diameter of pin in one-fourth inches (1/4") squared and divided by three (3)1/2" diameter == 2 quarters2 x 2 / 3=1 1/3 tons

ChainsSafe load in tons is 6 times diameter of chain stock in inches squared.1/2" diameter chain stock1/2 x 1/2 x 6 = 1 1/2 ton

Planks for scaffold2 x 10 or 2 x 12 plank, graded for 1500 psi bending stress, may normally be usedfor a span in feet equal or less than the width in inches.

Wire Rope: Nominal strength SWL rule of thumbSize 6 x 19 FC 6x19 IWRC 6x19 IWRC 7x19 AC SWL = rope dia. X rope dia. X 8 1/16 IP XIP 480 lbs. 1/2" x 1/2" x 8 = 2 tons 3/32 1000 lbs. 1/8 2000 lbs. 3/16 4200 lbs. 1/4 2.74t 2.94t 3.40t 7000 lbs. 5/16 4.26t 4.58t 5.27t 9800 lbs. 3/8 6.10t 6.56t 7.55t 14400 lbs. 1/2 10.7t 11.5t 13.3t 5/8 16.7t 17.7t 20.6t

Criteria for removal from service ANSI/ASME B30.9 Wire rope slings: A wire rope sling shall have no less than 10 times the wire dia between sleeves/spliceseg. 1/2" sling would be 5"Evidence of heat damage1/3 wear of outside wiresKinks, Crushing, Unstranding, Birdcaging, Corrosion, Distorted rope structureDamaged end attachmentsNumber broken wires in One rope lay: 10, in One strand: 5 Or ONE valley break

Efficiencies wire Angle of choke: Reduction factorSockets Zinc type 100% 121 - 135 0.95Wedge sockets 70% 91 - 120 0.82Clips 80% 61 - 90 0.71Knot and clip 50% 31 - 60 0.6Plate clamp 80% 0 - 30 0.48Mech. Eye <1/4" 95%Mech. Eye 5/16- 3/4" 90%Mech. Eye 7/8 - 1" 85%

Safety Factors:Overhead li 6:1Guy lines 3.5:1Wire Rope 5:1Mine Shaft 8:1 3000' or more 4:1

D/d ratios 30:1 -5% 10:1 -15% 2:1 -35%1.5:1 -50%

Nicopress: ( This is a partial list of Nicopress tools and sleeves)(Refer to Nicopress guide for proper installation instructions)

Cable size Tool No. Sleeve No. Groove # presses1/16" 64-CGMP 51-C-887 18-1-C;28-1-C;188-2-VC;428-2-VCoval C 11/16" 51-B4-887 168-2-VB4 oval B4 1

3/32" 64-CGMP 51-G-887 18-2-G;28-2-G;428-3-VG oval G 13/32" 64-CGMP 51-G-887 188-3-VG oval G 2 overlapped1/8" 64-CGMP 51-M-850 18-3-M;28-3-M;188-4-VM;428-4- oval M 31/8" 63V-XPM VM oval M 31/8" 51-MJ SAME AS ABOVE M 23/16" 63V-XPM 51-X-850 18-6-X;28-6-X;188-6-VX;428-6-VX oval X 43/16" 51-P-850 168-6-VP oval P 43/16" 3-X-850 3V-XPM 18-6-X;28-6-X;188-6-VX;428-6-VX oval X 23/16" 3V-F6:X:M SAME AS ABOVE oval X 23/16" 51-MJ 871-19-M; 878-5-M M 13/16" 3-MJ 871-20-M; 878-6-M M 11/4" 3V-F6:X:M 3-F6-950 18-10-F6;28-10-F6;188-8-VF6 oval F6 31/4" 3V-F6:X:M 3-F6-950 428-8-VF6 oval F6 31/4" 3V-F6:X:M 3-F6-950 871-23-F6;878-8-VF6 oval F6 2

Fleet AngleFleet angle is that angle included between lines drawn from the center of the drum and from the flange of the drum, to the lead sheave.Up to 2 degrees for flat faced drumsUp to 4 degrees for groove drums

Drum & Reel capacities:Length of rope in feet = Constant x (A + B) x A x C (all dimensions in inches)Dia. Multiplier Table for constants .2618 / d21/8" 16.78 A = Flange height3/16" 7.48 B = Drum dia.1/4" 4.19 C = Drum width3/8" 1.867/16" 1.371/2" 1.05

(eg. 1/4" cable on a drum; a = 3"; b = 6"; c = 12".4.19 *(3 + 6) * 3 * 12 = 1357.56'

Rope: Cordage Institute Rope Specs. Rule of thumb for SWLSize Manila Polypro Nylon Manila 1/2" rope = 4/8 inch1/4" 540 1130 1490 SWL = 4 x 4 x 20 =320 lb.3/8" 1220 2440 3340 Nylon 1/2" rope = 4/8 inch1/2" 2380 3780 5750 SWL = 4 x 4 x 60 =960 lb.5/8" 3960 5600 9350 Polypro 1/2" rope = 4/8 inch3/4" 4860 7650 12800 SWL = 4 x 4 x 40 =640 lb.

Polyester 1/2" rope = 4/8 inchSWL = 4 x 4 x 60 =960 lb.

PolyetheleneSplicing: SWL = 4 x 4 x 35 =560 lb.Eye splice: Manila : 3 full tucks

Synthetic: 4 full tucksTail shall be no less than 6 rope dia from last full tuck( 1" dia or less)Minimum clear space between eye splices 10 times rope dia.Knots shall not be used in lieu of splicing.

Knots efficiencies ropeClove hitch 75%Bowline 53%Square Knot 43%Timber hitch & Half 72%Sheepshank 35%Short splice 85%Long splice 68%Eye splice 85%

Fleet angle is that angle included between lines drawn from the center of the drum and from the flange of the drum, to the lead sheave.

Formulas: (Warning: Check results with a qualified engineer before using)Formulas Included:

Inclined planesUseful formulasAngle of chokeD/d ratiosContinuous beam

Block and Fairlead Loading(fill in line pull column in poundsfor block load)Angle Block factoLine pull Block load

180 0 1,000 - 150 0.52 1,000 520 120 1 1,000 1,000

90 1.41 1,000 1,410 60 1.73 1,000 1,730 0 2 1,000 2,000

Bridle height comparison chart

See how by moving leg B down in One foot increments how it affects leg A

Inclined planesStress on line when pulling objects up inclined plank on rollers

Rise in 10' Grade % Pull on line in Pounds per Ton Degree1' 10 240 5.72' 20 440 11.33' 30 620 16.694' 40 780 21.85' 50 930 26.566' 60 1070 30.967' 70 1180 34.998' 80 1280 38.659' 90 1370 41.9810' 100 1440 4512' 120 1560 50.1914' 140 1650 54.5616' 160 1720 57.9918' 180 1770 60.94

Coefficients of Friction:Concrete on concrete 0.65 Manila rope on wood 0.4 Continuous lubricated 0.15Metal on concrete 0.60 Leather on metal 0.4 surfaceWood on wood 0.50 Wood on metal 0.3 Steel on steel 0.1Wood on concrete 0.45 Cast iron on steel 0.25 Load on wheels 0.05

Mass, Weight & ForceMass is the property of a body by which is experiences mutual attraction to another body.

At sea level where Gravity is 1 G, weight and mass are equal.Weight is the gravitational force acting on a body. A body that weighed X at sea level

would weigh less than X on top of Mount Everest because the force of gravityis less. The mass would remain constant.

Force is the action of one body on another. A force tends to move a body in the directionof its action.

English Units SI UnitsMass Pound mass (lbm) Kilogram (kg)

Ton = 2000 lbm Ton = 1000 kgForce Pound force (LB) Newton (N)

Kilo-pound (kip) = 1000 LB Kilo-Newton (kN) = 1000 NAt sea level 1 lbm = 1 LB 1 kg = 9.81 N

English to SI SI to English1 lbm = .454 kg 1 kg = 2.20 LB2000 lbm = 907 kg 1000 kg = 2200 LB1 LB = 4.45 N 1 N = .223 LB1 kip = 4.45 kN 1 kN = 223 LB

Useful formulas:

Circumference of a circle Diameter x 3.1415 Area of a circle Square of diameter x .8 (.8 x D x D)Area of a triangle Base x 1/2 heightArea of a rectangle Base x heightVolume of a cone 1/3 Height x area of base (V = A x H/3)Volume of a sphere Cube of diameter x 0.5236 (D x D x D x 0.5236)Volume of a solid Area of base x heightVolume of a cylinder .8 x D x D x heightor round bar stockWeight of a solid Volume x weight per cubeWeight of a floating object Weight - L x B x D x 64 = Lb.

L = LengthB = Breadth (width)D = Draft64 = lbs. Of sea water per cubic foot

H = Height W =Width L = Length d = dia. r = 1/2 dia pi = 3.14Area of a square or rectangle = HWVolume of a cube = HWLArea of a circle = pi r 2Circumference = pi dThe area of a circle is approx. 80% of its diameter squared (dia x dia)Load Weight (to estimate) Volume in cubic feet x 500 lbs. x density factor .02, .05, .10, .20, .30 etc.

Angle of choke: Reduction factor D/d ratios121 - 135 0.95 30:1 -5%91 - 120 0.82 10:1 -15%61 - 90 0.71 2:1 -35%31 - 60 0.6 1.5:1 -50%0 - 30 0.48

Continuous beamThis chart shows the percentage of weight on each hangpoint on a trussor beam with 2 or more hangpoints.Note: This is considering an evenly weighted truss with even tension onall hangpoints.Note 2: When figuring loads keep in mind that a small bump in one motor can drasticallychange the weight on any hangpoint to the point of taking the entire weight for an inner motor.# points 1 2 3 4 5 6 7 82 points 0.5 0.53 points 0.18 0.625 0.184 points 0.133 0.367 0.367 0.1335 points 0.098 0.286 0.232 0.286 0.0986 points 0.079 0.226 0.195 0.195 0.226 0.0797 points 0.066 0.189 0.16 0.17 0.16 0.189 0.0668 points 0.056 0.162 0.138 0.144 0.144 0.138 0.162 0.056

Synthetic Slings:Nylon Slings From Westco brand catalogEnvironmental Considerations:

Acids Alcohol Aldehydes Strong Bleaching Dry Cleani Ethers KetonesAlkalis Agents Solvents

Nylon No OK OK OK NO OK OK OKPolyester * OK NO ** OK OK NO OK

* Disintegrated by concentrated sulphuric acids** Degraded by strong alkalies at elevated temperaturesNylon and Polyester slings should not be used at temperatures in excess of 194 deg. F (90 deg. C)To prevent mechanical or chemical damage when not in use, slings should not be exposed to sunlight and must be stored in a cool, dry and dark place.

Inspection: Key things to look for prior to useAcid or Caustic Burns Excessive Abrasive WearMelted, Charred or Welded Splatter Knots in any part of the slingBroken or Worn Stitching Holes, Tears, Cuts, Snags, Red Core Yarn Showing or Embedded particlesDamaged Loop Eye Any other Damage

Polyester RoundslingsItem # Color Vertical Choker BasketE30 Purple 2,650 2,120 5,300 E60 Green 5,300 4,240 10,600 E90 Yellow 8,400 6,720 16,800 E120 Tan 10,600 8,500 21,200 E150 Red 13,200 10,560 26,400 E180 Orange 16,800 13,440 33,600 E240 Blue 21,200 17,000 42,400 Resistant to Acids, Ultra Violet Rays, Rot and MildewMaximum temperature 194 deg. F

Crude Oils LubricatingSoaps & Water & Weak HydrocarbonsOils DetergentsSea Water Alkalis

OK OK OK OK OK OKOK OK OK OK OK OK

Hardware:

Eyebolts: Crosby Quenched and Tempered Shoulder type drop forgedDia. Vertical 60 deg 45 deg less than 45 90 deg. Non shoulder 1/4 650 420 195 160 5/16 1,200 780 360 300 3/8 1,550 1000 465 380 13 1/2 2,600 1690 780 650 37 5/8 5,200 3380 1560 1300 65 3/4 7,200 4680 2160 1800 100 7/8 10,600 6890 3180 2650 1531 13,300 8645 3990 3325 207Hoist Rings:5/16" 800 800 800 3/8" 1,000 1,000 1,000 1/2" 2,500 2,500 2,500 5/8" 4,000 4,000 4,000 3/4" 7,000 7,000 7,000 7/8" 8,000 8,000 8,000 1" 10,000 10,000 10,000

The Crosby Group, Inc.Shackles: Carbon Steel AlloySize 6:1 Design factor 5:1 Design factor3/16" 1/3 t1/4" 1/2 t5/16" 3/4 t3/8" 1 t 2 t7/16" 1-12 t 2.6 t1/2" 2 t 3.3 t5/8" 3-1/4 t 5 t3/4" 4-3/4 t 7 t

The Crosby Group, Inc. Drop forgedWire rope clips Fist grips Efficiency is 80% in this range

size Min. clips turn back torque Min. clips turn back torque 1/8 2 3-1/4" 4.5 3/16 2 3-3/4" 7.5 2 4" 30 1/4 2 4-3/4" 15 2 4" 30 5/16 2 5-1/4" 30 2 5" 30 3/8 2 6-1/2" 45 2 5-1/4" 45 7/16 2 7" 65 2 6-1/2" 65 1/2 3 11-1/2" 65 3 11" 65Appprox spacing between clips is 6 x rope diameter.Apply clip at rope end first, then closest to eye and the middle one last for those that need 3.Re torque after first load is applied.TurnbucklesSize SWL Eye SWL Hook1/4" 500 4005/16" 800 7003/8" 1,200 1,000 1/2" 2,200 1,500 5/8" 3,500 2,250 3/4" 5,200 3,000 7/8" 7,200 4,000

1" 10,000 5,000

Safety Factors:Overhead li 6:1Guy lines 3.5:1Wire Rope 5:1Mine Shaft 8:1 3000' or more 4:1

D/d ratios 30:1 -5% 10:1 -15% 2:1 -35%1.5:1 -50%

Bolt torque:The bolt takes two stresses during wrenching:1 Torsion, 2 Tension. Tension is what you want. Torsion is the necessary evil due to friction.Probably 90% of applied torque goes to overcome friction.

With the friction factor changed by lubrication, plating, etc., the torque needed to producea given tension is hard to predict. However, a useful empirical formula exists for normalfriction conditions.Inch-lbs. Torque = 0.2 x bolt diameter x bolt tension.Average deviation is about 7%

Bolt Head Markings:

Non-shoulder type eyebolt (forged steel) (from US Navy rigging handbook)size vert. 45 deg. 90 deg.1/2" 1100 51.5 37.69/16" 1500 69.8 515/8" 1800 89.5 65.63/4" 2800 136 1007/8" 3900 208 1531" 5100 280 207