外文翻譯-關(guān)于焊接滾輪架軸向竄動(dòng)的實(shí)驗(yàn)研究.doc

第1頁Jounalofmatenalsprocessingtechnology63(1997)881-886ExperimentandstudyintotheaxialdriftingofthecylinderofaweldingrollerbedFenggangshen,xidepan,jinxueWeldingresearchinstiute,xianjiaotonguniversity.Xian.shaanxiprovince710049.P.R.chinaAbstractThebasictheoryoftheaxialdriftingofthecylinderofaweldingrollerbedisintroducedinthepaper,andatthesametimeexperimentandstudyonthemechanismoftheaxialdriftingofthecylinderhavebeendoneonanexperimentalmodeloftheweldingrollerbed.Itisshownthatthemaincauseoftheaxialdriftingofthecylinderliesintheexistenceofaspiralanglebetweenthecylinderandthecylinderandtheroller.therelativeaxialmotionsbetweentherollerandthecylinderarecomposeofspiralmotion,elasticslidingandfrictionalsliding.Thetheoryofcompatiblemotionandnon-compatiblemotionisputforwardfortheaxialmotionsofthecylinder.therelativeaxialmotionsofthecylinder.TherelativeaxialmotionbetweentherollersandthecylinderiscoordinatedbyelasticslidingandfrictionalslidingbetweenthemKeywords:weldingrollerbed；cylinder；roller；axialmotion；spiralangle1IntroductionInweldingproduction,theassemblyandcircularseamweldingofrotaryworkpieces,suchasaboiler,apetrochemicalpressurevesselandsoon,areconductedon；aweldingrollerbed.WhenrotatingOnaweldingrollerbed.Thecylindewillinevitablyproduceaxialdriftingduetomanufacturing,assemblingtoleranceoftheweldingrollerbedandthecylinderssurfaceirregularity(divergiugfromanidealrotaryworkpiece),thustheweldingproceduremaynotbecarriedoutsuccessfully.Itisnecessary,therefore,tostudythemechanismoftheaxialdriftingofthecylindertosolvetheproblemoftheaxialdriftingofthecylinderincircumferentialwelding.Theresultsoftheresearchwillbenefitthestudyinganddesigningofantidriftingweldingrollerbed.especiallytheanalysisoftheappliedforcesonthebed,andleadtodeterminingthemanufacturingandassemblingtoleranceofthebed,andprovidingthebasisoftheoryforthemechanicaladjustingmodetoavoidaxialdrifting,theadjustingmodeofclosedcircuitinthecontrolcircuit,andtheselectionoftheadjustingvalue.2.Theoreticalanalysis2.1.WeldingrollerbedandcylinderAweldingrollerbedisgenerallycomposedoffourrollers.Drivenbythe第2頁drivingroller,thecylindermakesarotaryuniformmotionarounditsaxis(showninFig.I),duringwhichthecircumferentialweldingprocedureiscarriedoutInFig.1,aisthecentralangle,Sisthesupportingdistance,Listhespanoftheroller.andV,isthecircularlinearvelocityofthecylinder,alsonamedtheweldingvelocity2.Theaxisofthecylinderwillbenotparalleltothatofarolleriftherollerisdeflectedbyacertainanglefromthedealposition,orifthecentersofthefourrollerslieintheverticesofasimplequadrilateral,orifthecentersofthefourrollersarenotonthesameplane,orifthecircu-larityofthecylinderisirregularbecauseofdeviationinmanufacturingandassembling.Thus.thecylinderwillnevitablymovealongitsaxiswhenrotatingonabedthecontactofthecylinderandarollercanbecansideredaspointcontactifcytindersaxisandrollersaxisdonotlieinthesameplane.SupposePisthepointofcontact.thecylindersnormalplaneAisdefinedbytheplaneonwhicharethecylindersaxisandgeneratrixnacrossthepointoftangencyonthecylinder(showninfig2)makeacylinderstangentplaneBacrosspointP.Thus,planeAisverticaltoplaneB.lcisacylinderstangentacrossPandliesinplaneB.IristherollerstangentacrossthesamepointP,andliesinplaneBalso.Ingeneral,isdefinedastheaxialdeviationanglebetweentherol!ersaxisandthecylindersaxis；isdefinedasthespiralanglebetweengeneratrixnandm.aprojectivelineobtainedbyprojectingtherollersgeneratrixmacrosspointponplaneBandisdefinedastheprojectiveanglebetweennandm,aprojectivelineobtainedbyprojectingmonplaneA.Fig.3indicatesthattherela-tionshipamongstthethreeanglesistan=tan2-tan2InFig.3,SB,SandS,arecalledthespiraldisplace-mentvector,theaxialdeviationdisplacementvectorandtheprojectivedisplacementvectorrespectively.theirrelationshipbeing:第3頁Fig.2GeometricrelationshipbetweenthecylinderandanindividualrollerFig.3Relationshipbetweentheanglevectorandthedisplacementvector2.2.2relativeaxialmotionsrelationship(1)spiralmotion2.Fig.4ComponentofaxialvelocityBecausetherollersaxisisnotparalleltothecylin-derscentralline,thereisaspiralanglebetweenVr,.andVc,onthepointofcontact(showninFig.2).Whentherollerandcylinderrotatesynchronisticallyaroundtheirownaxes,drivenbytangentialfrictionalforce.aspiraleffectwilloccurbecauseofthedifferent第4頁linearvelocitydirectionbetweentherollerandthecylinderatpointPofcontactThecylinderhasacomponentofaxialvelocity,whereVcisthecircularlinearvelocityofthecylinder.isthecylindersaxialcomponentvelociryexertedbysingleroller,andjcanbe1.2,3,4,representingthefourrollers,respectively.(2)ElasticslidingBecauseoftheexistenceofaspiralangle,anaxialforceFajactsoncylinder.WhentheforceislessthanthemaximumaxialfrictionalforcefNj(wherefisthefrictionfactor,andNjisthenormalpressurebetweenasinglerollerandthecylinder),thecylinderwillslideelasticallyovertherolleralongtheaxialdirection23Thecomponentoftheslidingvelocityis.whereeistheelasticslidingfactorformetallicroller.e=O.OOl0.005.(3)FrictionalslidingWhenFajisgreaterthanthemaximumfrictionalforcefNj,thecylinderwillmakeafrictionalslidingovertheroller.TheslidingresistanceisfNj3.ThecomponentofthefrictionalslidingvelocityonCylinderisVajthemagnitudeanddirectionofwhichcanbedeterminedbytheuniversalrelationshipbetweenthecylinderandthefourrollersFrictionalslidingwillleadtothewearandtearofthesurfaceofthecylinderandtherollers.whichisunexpectedinweldingproductionWhenthecylinderdrifts,abovethreekindsofmotiondonotoccursimultaneouslyIhereforc.theaxialdriftingvelocityofthecylinderisnotthealgebraicsumofthethreecomponentsofvelocityInthecaseofelasticsliding,theaxialvelocityis.2.3axialmotionofthecylinderonaweldingrollerbed2.3.1AxialcompatiblemotionUnderid