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Contents

2 Projectplanning 11-26 2.1 Listofformulae 12 2.2 Suggestionsforinstallation 13-142.2.1 Verticalinstallation 132.2.2 Horizontalinstallation 14 2.3 ServicelifeLh 15 2.4 Guidelinesforuse 15-162.4.1 Dirtprotection 152.4.2 Corrosionprotection 152.4.3 Itemsrequiringregularlubrication 16 2.5 Ambienttemperatures 16 2.6 Precisionratings 172.6.1 Axialplay"a" 172.6.2 Lateralplay"b" 172.6.3 Toothprofileplay 172.6.4 Screwleaderror 17 2.7 Specialoperatingareas 18 2.8 Dimensioningofwormgearscrewjacks 19-212.8.1 Flowdiagram 192.8.2 Example 202.8.3 Manualoperationforliftingelements 202.8.4 Motordriveforliftingelements 202.8.5 Adjustmentandstoppingaccuracy 21 2.9 Permittedoperatingsettings 21-222.9.1 General 212.9.2 Operatingfactors 22 2.10 Dimensioningofliftingsystems 232.10.1 Flowdiagram 232.10.2 Example 23 2.11 Schematicdrivesystemlayout 24-262.11.1 Singledriveunit 242.11.2 Multi-screwliftingsystem 252.11.2.1 Mechanicallysynchronized 25-262.11.2.2 Electricallysynchronized 26

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2

2.1Listofformulae

Index

HE Wormgearscrewjack

Anl Liftingsystem

Ku Ballscrew

Tr Trapezoidalscrew

zul Permissible

ConfigurationconformingtoEN1570,EN280,EN-1756,EN1493(VBG14)Leadangle:2,4°<w<4,5° Ó Motorwithsinglebrakingtorquew>4,5° Ó Twoindependentbrakingsystems

StandardsfortheatrestagesandbroadcastingstudiosBGVC1(VBG70)Similar to configuration conforming to VBG 14, althoughself-locking screw is not an absolute requirement if alltorquetransmittingcomponentsaredesignedtowithstandtwicetheratedload.

Abbr. Designation Measuringunit Formula

w(•) Leadangle ° w=arctan[Ph/(d2*p)]

Self-lockingduringshutdown*:2,4°<w<4,5°

(Self-lockingoutofactuation:w<2,4°)

Notself-locking:w>4,5°

hAnl Liftingsystemefficiencyrating

hHE Wormgearscrewjackefficiencyrating

a Acceleration m/s2 a=v/(60*t)

As Numberofloadcycles

C Dynamicloadrating kN

Co Staticloadrating kN

d2 Pitchdiameter mm

ED Dutyratio %/hr ED=[lift*As/(60*v)]*100%

Fdyn Dynamicaxialforce(=liftingforce) kN

Fstat Staticaxialforce(=retentionforce) kN

HU Liftperrotation mm HU=Ph/i

i Transmissionratio

Lh Servicelife h Lh=(C/Fdyn)3*106/(n2*60)

n1 Inputspeed min-1

n2 Outputspeed min-2 n2=n1/i

P Powerrating kW P=Fdyn*v/(60*h)

Ph Screwlead mm

pv-value Surfacepressurexslidingspeed N/mm2*m/min

pzul Permittedsurfacepressure N/mm2

t Time s

T1 Drivetorque Nm T1=P*9550/n1

T2 Outputtorque(=screwtorque) Nm

TA Startingtorque Nm TA~T1* 1,3

v Liftingspeed m/min v=n1* Ph/i

(•)Vibrationsandoptimizedslidingpropertiesmayaffecttheself-lockingsystem.Ifindoubt,useamotorbrake.

ProjectplanningProjectplanning

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2.2Suggestionsforinstallation

2.2.1Verticalinstallation

Recommendedarrangementforlargeliftingcapacitiesandlongscrews

Tensileload

Design:Configurationtype1Withclimbingscrewjacks(withoutprotectiontube)

Compression-loadedscrewswithoutlateralguides

DimensioningofscrewaccordingtoEuler’scaseI

Design:Configurationtype1Withliftingscrewandprotectiontube

Arrangementwithcompression-loadedscrew,possiblewithorwithoutadditionalguides

DimensioningofscrewaccordingtoEuler’scaseIIIandcriticalscrewspeed

Design:Configurationtype2Withrotatingscrewandtravellingnut

Swivellingmovementsrequirearticulatedmounting

DimensioningofscrewaccordingtoEuler’scaseII

Design:Configurationtype1Withliftingscrew,twoguideringsandprotectiontube

S=safetyclearanceSeechapter7"Accessories”fordetailsofallrequiredadd-onitems(connectingflanges,swivelmountingbasesetc.).

Pict.4

Pict.1

Liftingplatform(Load)

Connectingshaft

usea

ble

stro

ke

HeadtypeII

HeadtypeIV

Pict.2

Connectingshaft

usea

ble

stro

ke

Liftingplatform(Load)

Pict.3

usea

ble

stro

ke

Connectingshaft

Standardtravellingnut

Travellingnutwithsphericalpivotingsuspension

Liftingplatform(Load)

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2

2.2Suggestionsforinstallation2.2.2Horizontalinstallation

Intermediatebearing-supportofa12mscrew

Standard once-piece screws can be made in lengthsofupto6m(3mforscrewsmadeofrust-freemate-rial). Longer screws are supplied in sections to makeinstallationonsiteeasier.

Specialtravellingnut

If critical screw speed is exceeded (only applies toconfigurationtype2=rotatingscrew),thescrewsmustbeadequatelysupported.Thisrequirestheuseofourspecially-supplied intermediate bearings and travellingnuts(seephotos).

Arrangementwithcompression-andtension-force-loadedscrewWithguidessuppliedonsite

DimensioningofscrewaccordingtoEuler’scaseII,ifscrewretainingforceisinsuffici-ent.Otherwise,applyEuler’scaseIII

Design:Configurationtype1Withclampedscrewandlineartraversingdriveaxis.

Arrangementwithcompression-andtension-force-loadedscrewWithguidessuppliedonsite

DimensioningofscrewaccordingtoEuler’scaseIIIandcriticalscrewspeed

Withscrewspre-adjustedtotensileloadÓ

Dimensioningaccordingtocriticalspeedonly

Design:Configurationtype2Withrotatingscrewandtravellingnut

Pict.5 Pict.6

Pict.7 Pict.8

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2.3ServicelifeLh

The design and construction of Pfaff-silberblau worm gear screw and quick-lifting jacks are based on our long years ofexperienceinthefieldandtheyhavealongservicelifeiftheinstructionsintheoperatingmanualsareobserved.

Themaximumloadvaluesgiveninthecataloguedata(tablesofsettings)arebasedonaservicelifeofminimum500operatinghours.

2.4Guidelinesforuse

2.4.2Corrosionprotection

Corrosionprotectedaluminiumhousingsfittedtothefollowingranges:SHE Size0.5and1.1MERKUR SizeM0,M1andM2HSE Size32and36.1SHG SizeG25

Surfacecoatingforallothersizes:•SHEandHSEhousingswithseries-applied primecoat•MERKURandSHGwithphosphatecoatedhousings

Optionalcorrosionprotectionforspecialconfigurations:Availableforallranges:•Specialcoatings•Screwsandscrewheadsmade ofmaterial1.4305,1.4301,1.4571•Worm-driveshaftsmadeofrust-freematerial•SHErangeincompletelyrust-free materialconfiguration

Corrosionprotectionprovidedbysurfacecoatings:Availableforallranges:•Tenifertreated(salt-bathnitrided)•Hard-chromeplateddriveshafts

SHGG25(aluminiumhousing)

Screw Gearinglayout Bearinglayout

TrandSscrew Kuballscrew NorL Thrustandradialbearings

•Thesevaluesareforguidanceonly,

asexactcalculationisnotpossible

•Decisivelayoutfactorsaresurface

pressureandslidingspeed

(pv-value,pzul)

• Guaranteedrelubrication

• Idealinstallation

•Calculation:

Lh=(C/Fdyn)3*106/(n2*60)

Worm-drivegearing:

• SHEstandardwormscrewjackand

MERKUR:approximatevaluesaccording

toDIN3996-D

• InthecaseofHSEhighperformanceworm

gearscrewjack,accordingtoDIN3996-C

Bevelgeartoothsystem:

•SHGquick-liftingscrewjacks,Lh=fatigueendurable

• Calculationsaccordingto

DINordatasuppliedby

thebearingsupplier

2.4.1Dirtprotection

• Leakproofingofallrangesbymeans ofrotarylipsealsfittedtodriveshaftsisstandard• EnclosedhousingconfigurationonHSEundSHG rangesusingadditionalseals• Screwprotectiontubefortype1

Optionalliftingscrewprotectivecovers:• Flexibleprotectionbootsmadeofvariousmaterials toprevententryofdirtandforoutdooruse (water-proof)• Spiralspringcoverforuseinextreme environment(flyingswarf,weldingsparks)

Specialconfigurations:Specialconfigurations,e.g.foruseunderwaterorathightemperatures,areavailableonrequest

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2

2.4Guidelinesforuse

Ifaccesstothescrewitselforthelubricationpointsonthehousingisdifficult,werecommendtheuseofacentrallubricationsystemorautomatic lubricantdispenser (seechapter7.8).Ourcomponentscanbesuppliedwith thenecessaryscrew-inconnections for thispurpose.

SHEandMErKurrange

Configuration Lubricationpoint

Type1 guidering,protectiontube,housing

(gearinglayout)

Type2 travellingnut,housing(gearinglayout)

HSEandSHGrange

Configuration Lubricationpoint

Type1 guidering,protectiontube

Type2 travellingnut

2.5Ambienttemperatures

2.4.3Itemsrequiringregularlubrication

Standard

-10°C + 40°C

T< -10°C

-Speciallubricants,max.-30°C

-Specialmaterials(onrequest)

+ 40°C<T<_80°C

-Speciallubricants,max.+80 °C

-SpecialmeasuresT>80°C

(onrequest)

Note:PleasetakeourreducedperformanceorED-(dutyratio)

valuesintoconsiderationiftemperaturesdeviatefromthestandardsgiven.

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2.6Precisionratings2.6.1Axialplay„a”

Axialplayhasnoinfluenceonpositioningaccuracyinthecaseofone-sideload,astheflanksofthescrewthreadprovidesupport.

2.6.2Lateralplay„b”StandardLateralplay„b”occursonlyinthecaseoftype1,asaresultofplaybetweentheguideringandtheouterdiameterofthescrew.Itcomesuptoabout0,2mmandeffectsa linearcalculativedeviation„b“dependingonstroke length.Theamountofplay„b”canbereducedbymeansofasecondguidering.

Specialconfiguration2ndguideringwithreducedplayandadditionallygroundscrewmaterial.

2.6.3Toothprofileplay

Wormgeartoothconfiguration

Bevelgeartoothconfiguration

The tooth profile play (when new) of 0,1 – 0,3 mm varies,depending on the size of the unit resp. centre distance ofshafttowheel,withtherateofwear.

Toothprofileplayof0,05–0,1mmkeptconstantthroughoutservicelifeofunit.

2.6.4Screwleaderror

TrapezoidalscrewthreadconformingtoDIN103T1; ButtressscrewthreadconformingtoDIN513

Whirledscrew(standard)±0,05mm

Rolledscrew±0,1mm

Trapezoidalorbuttress-threadscrew

Standard

0,1mm[a[0,3mm,dependingonsize

Modifiedconfiguration:

Axialplaycanbereadjusted

Ballscrew

Singleflangenuta[0,05mm

Initialtensiondependingonsizeofball

0,01mm[a[0,03mm

Pre-stresseddoublenuta[ 0,01mm

BallscrewthreadconformingtoDIN69051T3

Whirledscrew(standard)ToleranceclassificationT7;P300=0,052mm

Groundscrew;toleranceclassificationT1-5;P300=0,006-0,023mm

Rolledscrew;toleranceclassificationT9;P300=0,1mm

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2.7Specialoperatingareasofapplication

• Specialsealingwith non-toxiclubricants

• Corrosionprotection (rust-freematerials)

• Travellingnutsmadeof self-lubricatingmaterial

e. g. use of approved materi-als with inspection certificatepursuanttoDINEN102042.2-3.1B-3.1C

•Greasingwithradiationresistantlubricants

•Earthquakeproofconfiguration

Wehavemanyyearsofexperienceintheareaofspecialapplicationsfor

linearactuatortechnology,andcanofferthefollowingservices:

Underwater Inpotentiallyexplosiveareas

Wormgearscrewjacksandliftingsystemsinspecialconfiguration

Incontaminatedareas

•Projectplanning

•Designsupport

•Materialtestingandcertification

•Supervisionofinstallation

proceduresandinitialstart-up

•Project-relateddocumentation

• Wormgearscrewjacks accordingto ECDirective94/9/ECATEX inequipmentgroupII- Zone1/21(2/22)withc/k/b protectionandtemperature classT1andT4

• Useofapprovedelectrical components,suchasmotors, limitswitches,pressure-resistant sealedbrakeunitsconforming tothecorrespondingtypeof protectionandtemperature class

Projectplanning Projectplanning

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2.8Dimensioningofwormgearscrewjacks2.8.1Flowdiagram

Selectedgearsizecanbeapplied

Tensileload

No

Screwdiameterasdisplayedinchapter3.4.2Note:Areinforcedscrewdiametercanbe

usedfortype2jacks(rotatingscrews)

Compressionload

Checkaccordingtochapter

2Projectplanning3.1Constructionsupport

orconsultourscrewjackspecialists

Hotline:Phone+49/8233/2121-4100

antriebstechnik@cmco.eu

TechnicalinformationSeechapter3

Forexample:Efficiencyratingsandperformancetables

Yes

Areadditionalconditionstobeobserved?

•Extraordinaryoperatingconditions•Shocks/Strokes

•Lateralloads•Dutyratio>20%/h

•Standardstobeobserved,e.g.VBG14(elevatingplatforms),

BGVC1(theatrestagesandbroadcastingstudios)

Pre-selectiondependsonperformancelimitsofscrewjackanddiameterofscrew.Tablesofsettings,chapter3.4.1

DeterminedutyratioED[%/h];determinepowerratingP[kW](seeformulaecollectioninchapter2.1)

Dimensioningofscrewaccordingtoloaddirection

Axialforce[kN]Fdyndynamicforce

Fstatstaticforce(retentionforce)Liftingspeedv[m/min]

Stroke[mm]Determineconfiguration

(type1ortype2)

Euler’scaseI

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2

2.8Dimensioningofwormgearscrewjacks2.8.2Example

2.8.3Manualoperationforliftingelements

2.8.4Motordriveforliftingelements

Motordesigns:

requiredstartingtorque TA~1,3xTN

Highliftingspeeds,e.g.servodrivesystem Inertialmassandaccelerationtimeare

decisivefactorsforconfiguration

Screw Frombucklingdiagram Tr50x9

Pre-selectionofwormgearscrewjack Chapter3.4.1 HSE63.1

Requireddriveperformance 2,0kW Performancelimitaccording

totableofsettings,chapt.3.4.1Perf<pzul=2,3kW

Dutyratio 11%/h Forformula,seechapt.2.1 EDvorh<EDzul=20%/h

Selectedmotor 2,2kW,1500min-1

SelectedsizeHSE63.1isok

RatioN

T1=higher

Lift/Rotation=larger

Manualoperation

RatioL

T1=lower

Lift/Rotation=less

TakepossibledrivetorqueT1and/or

manualforceintoaccount

(valuesbasedonpastexperience:

approx.150tomax.200N)

NoED(dutyratio)checkrequired

Takethetypeofmotor(three-phase,DC,

hydraulicetc.)intoaccountwithrespecttostart-upchar-acteristics,impactcoefficient

andsoon

Observetheadditionalfrictioncoefficientsof

theguideelementsetc.

Observethemax.permitteddrivecapacityoftheliftingelement.

Seechapter3.4.1

Observethemax.per-mitteddutyratio.Seechapter3.4.1

Motordrive

Guidesfittedonsite YesÓ

Euler’scaseIII

Loadcycles/hour 10

Travelperloadcycle 1200mm

Configurationtype1(liftingscrew)

Singledriveunitwithmotor

RequiredaxialforceFdyn 20kN

Requiredliftingspeedv 1,9m/min

Requiredlift 1200mm

Selectedconfiguration Seechapter3.2

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2.8Dimensioningofwormgearscrewjacks2.8.5Adjustmentandstoppingaccuracy

The levelof adjustmentaccuracydependsmainlyon theprecisionof thescrew (seechapter2.6).Positioningaccuracy isinfluenced,inthecaseofmotor-actuatedunits,bytheelectricalcontrolandregulatingsystem,thecontrolsystemofthebrake,andbytheadjustmentprecisionofthelimitswitches.

IMPOrTANT:DONOTallowmotor-actuatedcomponentstocollidewithfixedend-limitstops!

2.9.1General

Lateralforceonscrew

Fs

Fordetailsofpermittedvalues,

seediagramsinchapter3.4.8

Drivecapacity

PHE<pzul

PHE=Fdyn*v/(60*hHE)

Forcalculationdetails,

seechapter2.1

Standardlayoutat

20%ED/hourand20°C,or

10%ED/hourand20°C

Dynamicandstatic

compression/tensileload

Fdyn/Fstat

Configurationaccordingtotableof

settingschapter3.4.1and/orbuckling

diagramsinchapter3.4.2

Axialloadondriveshaft

Fa

Noaxialloadspermitted

(Thisshouldalsobetakeninto

accountwhenfittingcouplingsand

connectingshafts)

radialloadondriveshaft

Fr

Fordetailsofpermittedvalues,see

chapter3.4.9

Drivetorque

T1<Tzul

T1=PHE*9550/n1

Forcalculationdetails,seechapter2.1

F a

Fs T1

Fr

Fdyn/Fstat

2.9Permittedoperatingsettings

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2

Powerfactorsk1,k2andk3applyspecificallytoHSEhighperformancewormgearscrewjacks.Theymustnotbeappliedtostandardwormgearscrewjacks,Merkursystemsorquick-liftingscrewjacks.

2.9Permittedoperatingsettings

Powerfactork1

Powerfactork1isthelostenergy(quantityofheat)thatcan be dissipated at ED 20 %/h and 20 °C ambienttemperatureofHSEwithoutanoutsidecoolingsystem.Thesteady-statetemperatureinthiscaseis80°C.

pzul=k1*k2*k3/(1-hHE)

Dutyfactork2

The duty factor k2 is the correction value used to in-crease or decrease the permitted drive capacity pzulwithadeviationof20%ED/h.At20%ED/hor30%ED/10minisk2=1.Ifthedutyratiodeviatesfromtheestablishedsettings,k2canbedeterminedusingthediagramshownhere.

Temperaturefactork3

Atnormaltemperaturesof20°C,thisfactoris1.Intheeventoffluctuatingambienttemperatures(=q),thisfactoriscalculatedasfollows:

80–q k3= 60

HighperformancewormgearscrewjackHSE

2.9.2Operatingfactors

StandardwormgearscrewjacksSHEandMErKur ReductionofEDrelativetoambienttemperature

Ambienttemperature[°C] 50° 60° 70° 80°

inthecaseofscrewjacksSHEandMErKur

Maximumpermitteddutyratio

%/h 18 15 10 5

%/10min 36 30 20 10

CAUTION:MaximumoperatingtemperatureHE=80°C

Ope

ratin

gFa

ctor

k2

RelatedTime(min)

Projectplanning Projectplanning

SizeHSE 32 36.1 50.1 63.1 80.1

Powerfactork1[kW] 0,40 0,64 1,0 1,62 2,43

SizeHSE 100.1 125.1 200.1

Powerfactork1[kW] 3,30 5,41 13,30

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2.10Dimensioningofliftingsystems2.10.1Flowdiagram

2.10.2Example

Technicalspecifications:Fges=60kN(dyn.andstat.)v=1,9m/minED=20%/hSchematicview4.1Three-phasemotorBevelgearboxi=1:1

Overallforce[Fges]ofthesystem[kN]

Liftingspeed

Selectschematicdrive-systemlayout(chapter2.11)

Numberandarrangementofscrewjacks,typeof

motor,connectingshafts,bevelgearboxes,

couplings

Configurebevelgearboxes,couplings,

connectingshafts(accordingtotorque

andturningspeed)

hAnl~0,8

hHEasshowninchapter3.4.1or3.4.5

*Factorforunequal

loaddistribution=1,3

Observethemaximumdrive

torqueondriveshaftof

screwjack

Ifnon-self-locking

liftingsystemsareinoperation,

fitthemotorwithaspring-

actuatedsafetybrake.

TAnl=minimumnominaltorque

ofmotor

startingtorque

TA~TAnl*1,3

Fges*v PAnl= 60*hHE*hAnl

PAnl*9550 TAnl= n1

PAnl*1,3 PHE= Numberofscrewjacks

Checkscrewjackasshowincapter2.9

DeterminetypeofmotoraccordingtoPAnl,turningspeed,with/withoutbrake,

torqueTA

FHE=60kN/4*1.3Pre-selectionofscrewjackaccordingtochapter2.8

Ì HSE63.1,Tr50x9,

FHE=19,5kN hHE=0,311;PHE=2,0kW,hAnl~0,8

PAnl=7,63kW Ì motorselection7,5kW,n1=1500min-1 Ì motor132M/4

TAnl=49Nm Ì TKeg=25Nm,i=1:1(chapter4) Ì bevelgearboxK11.13

TGW1=25Nm,n1=1500min-1;observemax.lengthaccordingtonkrit(chapter6) ÌconnectingshaftZR28/38

TGW2=12,5Nm,n1=1500min-1;observemax.lengthaccordingtonkrit(chapter6) Ì connectingshaftZR24/28

Bevelgearbox

Motor

Screwjack

Connectingshaft2

Connectingshaft1

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2.11Schematicdrivesystemlayout

2.11.1Singledriveunit

Wormgearscrew jack–coupling–motor inconfigu-rationB3(base-mounted)

Wormgearscrewjack–coupling–IECflangeincon-figurationB14orB5(IECflange-mounting)

withcoupling withIECflangeandcoupling

Pfaff-silberblauwormgearscrewjacksandquick-liftingscrewjackscan be used as either single drive units (see chapter 2.11.1) ormulti-screwliftingsystems(seechapter2.11.2).Multi-screwliftingsystems with mechanical synchronization are driven by a singlemotor,whichmakes them impervious tounequal loaddistributionanditsnegativeeffectsonthesynchronizationofthescrewjacks.Multi-screw lifting systems with electrical synchronization aredistinguished by their low requirements in terms of mechanicalconnectingelements(andthereforelackofrunningnoise),buttheydorequiremoresophisticatedcontrols.Preciseconfigurationofthedrivemotors, inconjunctionwithamaster-slave layout,producesthecorrespondingexactsynchronizationofthedrivesystems.Onceyouhavedecidedonthebestlayoutforyourneeds,youcanestablishwhichbevelgearboxes,couplingsandconnectingshaftsaretobefitted.Thefittingofpillowblockscanmultiplythespeed-dependentlengthoftheconnectingshafts.

Note:If quick-lifting screw jacks are in use, correct configuration caneliminatetheneedforbevelgearboxes.

Schematicview1.1

Symboles

Screwjack

Connectingshaft

Coupling

Standardmotor

Spurgearmotor

Pillowblock

Bevelgearbox

IECflange

-Wormgearmotor-Bevelgearmotor

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2.11Schematicdrivesystemlayout2.11.2Multi-screwliftingsystem

2.11.2.1Mechanicallysynchronized

Schematicview3.1

Schematicview3.2

Schematicview3.3

Design"C”Onlypossiblewithratio1:1

Schematicview2.1

Schematicview2.3

Schematicview2.2

Schematicview2.4

Design"C”Onlypossiblewithratio1:1

Design"C"ordesign"D"Allratiospossible

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2.11.2.2Electricallysynchronized

Master

Slave3

Slave1

Slave2

2.11Schematicdrivesystemlayout

Schematicview4.1 Schematicview4.2

Schematicview4.5

Schematicview4.3

Idealtorquedistribution

Design„C” Design„D”

Anyratiopossible,but„C”and„D“mustbethesame

Design„A”

Design„F”

Design„C”

Design„E”

Anyratiopossible,but"A”and"E”mustbethesame

Pillowblocksonlyrequiredwhenexceedingthecriticalspeed

Onlypossiblewithratio1:1

Closeloopfrequencycontrol

Projectplanning