外文翻译--金属板料的成形及冲裁.doc

1英文原文4Sheetmetalformingandblanking4.1Principlesofdiemanufacture4.1.1ClassificationofdiesInmetalforming,thegeometryoftheworkpieceisestablishedentirelyorpartiallybythegeometryofthedie.Incontrasttomachiningprocesses,ignificantlygreaterforcesarenecessaryinforming.Duetothecomplexityoftheparts,formingisoftennotcarriedoutinasingleoperation.Dependingonthegeometryofthepart,productioniscarriedoutinseveraloperationalstepsviaoneorseveralproductionprocessessuchasformingorblanking.Oneoperationcanalsoincludeseveralprocessessimultaneously(cf.Sect.2.1.4).Duringthedesignphase,thenecessarymanufacturingmethodsaswellasthesequenceandnumberofproductionstepsareestablishedinaprocessingplan(Fig.4.1.1).Inthisplan,theavailabilityofmachines,theplannedproductionvolumesofthepartandotherboundaryconditionsaretakenintoaccount.Theaimistominimizethenumberofdiestobeusedwhilekeepingupahighlevelofoperationalreliability.ThepartsaregreatlysimplifiedrightfromtheirdesignstagebyclosecollaborationbetweenthePartDesignandProductionDepartmentsinordertoenableseveralformingandrelatedblankingprocessestobecarriedoutinoneformingstation.Obviously,themoreoperationswhichareintegratedintoasingledie,themorecomplexthestructureofthediebecomes.Theconsequencesarehighercosts,adecreaseinoutputandalowerreliability.Fig.4.1.1Productionstepsforthemanufactureofanoilsump2TypesofdiesThetypeofdieandthecloselyrelatedtransportationofthepartbetweendiesisdeterminedinaccordancewiththeformingprocedure,thesizeofthepartinquestionandtheproductionvolumeofpartstobeproduced.Theproductionoflargesheetmetalpartsiscarriedoutalmostexclusivelyusingsinglesetsofdies.Typicalpartscanbefoundinautomotivemanufacture,thedomesticapplianceindustryandradiatorproduction.Suitabletransfersystems,forexamplevacuumsuctionsystems,allowtheinstallationofdouble-actiondiesinasufficientlylargemountingarea.Inthisway,forexample,therightandleftdoorsofacarcanbeformedjointlyinoneworkingstroke(cf.Fig.4.4.34).Largesizesinglediesareinstalledinlargepresses.Thetransportationofthepartsfromoneformingstationtoanotheriscarriedoutmechanically.Inapresslinewithsinglepressesinstalledonebehindtheother,feedersorrobotscanbeused(cf.Fig.4.4.20to4.4.22),whilstinlarge-paneltransferpresses,systemsequippedwithgripperrails(cf.Fig.4.4.29)orcrossbarsuctionsystems(cf.Fig.4.4.34)areusedtotransfertheparts.Transferdiesareusedfortheproductionofhighvolumesofsmallerandmediumsizeparts(Fig.4.1.2).Theyconsistofseveralsingledies,whicharemountedonacommonbaseplate.Thesheetmetalisfedthroughmostlyinblankformandalsotransportedindividuallyfromdietodie.Ifthisparttransportationisautomated,thepressiscalledatransferpress.Thelargesttransferdiesareusedtogetherwithsinglediesinlarge-paneltransferpresses(cf.Fig.4.4.32).Inprogressivedies,alsoknownasprogressiveblankingdies,sheetmetalpartsareblankedinseveralstages；generallyspeakingnoactualformingoperationtakesplace.Thesheetmetalisfedfromacoilorintheformofmetalstrips.Usinganappropriatearrangementoftheblankswithintheavailablewidthofthesheetmetal,anoptimalmaterialusageisensured(cf.Fig.4.5.2to4.5.5).TheworkpieceremainsfixedtothestripskeletonupuntilthelaFig.4.1.2Transferdiesetfortheproductionofanautomatictransmissionforanautomotive3application-stoperation.Thepartsaretransferredwhentheentirestripisshiftedfurtherintheworkflowdirectionaftertheblankingoperation.Thelengthoftheshiftisequaltothecenterlinespacingofthediesanditisalsocalledthestepwidth.Sideshears,veryprecisefeedingdevicesorpilotpinsensurefeed-relatedpartaccuracy.Inthefinalproductionoperation,thefinishedpart,i.e.thelastpartinthesequence,isdisconnectedfromtheskeleton.Afieldofapplicationforprogressiveblankingtoolsis,forexample,intheproductionofmetalrotorsorstatorblanksforelectricmotors(cf.Fig.4.6.11and4.6.20).Inprogressivecompounddiessmallerformedpartsareproducedinseveralsequentialoperations.Incontrasttoprogressivedies,notonlyblankingbutalsoformingoperationsareperformed.However,theworkpiecealsoremainsintheskeletonuptothelastoperation(Fig.4.1.3andcf.Fig.4.7.2).Duetotheheightoftheparts,themetalstripmustberaisedup,generallyusingliftingedgesorsimilarliftingdevicesinordertoallowthestripmetaltobetransportedmechanically.Pressedmetalpartswhichcannotbeproducedwithinametalstripbecauseoftheirgeometricaldimensionsarealternativelyproducedontransfersets.Fig.4.1.3ReinforcingpartofacarproducedinastripbyacompounddiesetNexttothediesalreadymentioned,aseriesofspecialdiesareavailableforspecialindividualapplications.Thesediesare,asarule,usedseparately.Specialoperationsmakeitpossible,however,forspecialdiestobeintegratedintoanoperationalSequence.Thus,forexample,inflangingdiesseveralmetalpartscanbejoinedtogetherpositivelythroughthebendingofcertainmetalsections(Fig.4.1.4andcf.Fig.2.1.34).Duringthisoperationreinforcingparts,glueorothercomponentscanbeintroduced.Otherspecialdieslocatespecialconnectingelementsdirectlyintothepress.Sortingandpositioningelements,forexample,bringstampingnutssynchronisedwiththepresscyclesintothecorrectpositionsothatthepunchheadscanjointhemwiththesheetmetalpart(Fig.4.1.5).Ifthereissufficientspaceavailable,formingandblankingoperationscanbecarriedoutonthesamedie.4Furtherexamplesincludebending,collar-forming,stamping,fineblanking,wobbleblankingandweldingoperations(cf.Fig.4.7.14and4.7.15).Fig.4.1.4AhemmingdieFig.4.1.5Apressedpartwithanintegratedpunchednut4.1.2DiedevelopmentTraditionallythebusinessofdieengineeringhasbeeninfluencedbytheautomotiveindustry.Thefollowingobservationsaboutthediedevelopmentaremostlyrelatedtobodypaneldieconstruction.Essentialstatementsare,however,madeinafundamentalcontext,sothattheyareapplicabletoallareasinvolvedwiththeproductionofsheet-metalform