外文翻译用于提高大批量零件生产率的五面加工中心.doc
南京工程学院毕业设计英文翻译课题名称:母线槽技术参数检测线运动机构控制系统设计学生姓名:指导教师:所在系部:专业名称:南京工程学院2006年03月1日Five-FaceMachiningCenterToBoostProductivityofLargePartsHideoTamonManagerMachiningSection,ManufacturingDept1.IntroductionMeetingincreasinglydiversemachiningneedsandmakingeffectiveuseofalimitedsupplyofpersonnelandavailablespaceareamongthemostimportantgoalsformachinetoolmanufacturers,andkeyconsiderationsinfindingwaystoachievethemare“productivity”and“accuracy.”Toachievehighermachiningaccuracyandproductivity,SNKsShinodayamaWorkhasbeencontinuingtomodernizeitsproductionfacilitiesandimprovetheproductionenvironment.Asoftheearly1960s,therewereatotalof310machinetoolsatShinedayamaWorks,butthehavenowbeenreplacedbyonly70highlyproductivemachines.Guidedconsistentlybytopmanagementsphilosophycenteredon“pursuitofautomation”and“functionalimprovement,”ShinodayamaWorkshasbeenworkingtoincreaseproductivityandrationalizeitsfacilities.Duringtheprocess,asingleactionthatwasmostinstrumentalinincreasingproductivitywastheintroductionofmachinetoolsdesignedtomachinefivefaces(sides)oftheworkpieceinonesetup.Overtheperiodoftenyearsfrom1990allfactorybuildingsweremodifiedintotemperature-controlledfactoriessoastoensuretheconsistentaccuracyofthemachiningandtheassembly(includingunitassembly)processesbystabilizingmachineandworkpieceaccuracy.Asaresult,themachiningcapacityofShinodayamaWorksbecamelargerthannecessarytomachinelargepartstobeusedinSNKproducts;itbecamelargeenoughtomachineotherpartsundercontractforothercompanies.Thisarticlewillintroducetothereaderstheadvantagesofthefive-facemachiningcenterintermsofproductivity.Theseadvantageswillbedemonstratedinadiscussionofthemachiningofaturbinecasingofalargegenerator,whichisofacylindricalassemblyofcomplexconfiguration.TheturbinecasingismachinedwithSNKsnewlydevelopedHF-8MMulti-Center,alarge,high-performance,precisionfive-facemachiningcenterinstalledatShinodayamaWorks.2.ConfigurationoftheWorkpiece(TurbineCasing)Asshowninfigure1,theturbinecasingtobemachineontheHF-8Misofsplitcylinderconfiguration.ThedimensionsoftheturbinecasingarealsoshowninFigure1.Thecasingismadeofsteelandweighsabout70tons.Themachiningprocessesofthisworkpiececanbesummarizedasfollows:ProcessA:Machiningofmatingsurfacesanddrillingofscrewandboltholes.ProcessB:MachiningofoutsideflangesurfacesanddrillingofholesProcessC:IDmachiningProcessD:Machiningofflangesurfaceanddrillingoffasteningscrewholes3.ComparisonBetweenFive-faceMachiningandConventionalMachiningFortheprocessesAtoDmentionedinSection2,themachinetoolsrequiredforthemachiningmethodusingafive-facemachiningcenterandthemachiningmethodusingconventionalmachinetoolswerecompared(Table1).Asshowninthetable,useofafive-facemachiningcenterisadvantageousintermsofproductioncontrolandworkpiecemachiningaccuracybecausethemovementoftheworkpiecefrommachinetomachineandsetupchanges(includingalignment)thatwouldberequiredfordifferentmachinesintheconventionalmachiningmethodcanbeminimizedbyusingafive-facemachiningcenter.4.FunctionofHF-8MMulti-CenterCapableofPerformingAllMachiningOperationsThissectiondescribesthefunctionsandcharacteristicsoftheHF-8Mthatiscapableofperformingallmachiningoperationsforaturbinecasing,alongwithsomenewlydevisedmachiningmethods.1)UsingvariousattachmentsandautomationdevicesTheHF-8MatSNKisequippedwithaseven-attachmentautomaticattachmentchanger(ACC)(Photo)anda100-toolautomatictoochanger(ATC).Byallowingthemachinetochangeattachmentsandcuttingtoolsautomaticallyasnecessary,therangeofmachiningoperationsthatcanbecarriedoutinonesetupcanbeexpanded,andefficiencyimprovementandautomationcanbeachieve.Themachiningoftheturbinecasingrequiredfourtypesofattachmentsincludinganewlydevelopedattachment:AngularattachmentExtensionattachmentUniversalattachment(withacalibrationsystem)Sidecutterattachment(newlydeveloped)2)Universalattachment+arbitrary-planemachiningfunctionAsshowninFigure1,theworkpiecehasmanyflangesurfacesandholesprotrudingbeyondtheoutsidesurfaceofthecasing.Theyarearrangedradicallyfromthecentralaxisofthecasing,areinclinedfromtheaxisdirectionandareofftheradialaxes.Theconventionalmachiningmethodistouseaninclinedattachmentmountedonahorizontalmachiningcenterwhiletheworkpieceisrotatedandpositionedonarotarytable.WiththeHF-8M,auniversalattachment(withacalibrationsystem)wasusedincombinationwiththearbitrary-planemachiningfunction(Photo3)Thearbitrary-planemachiningfunctionallowsarbitraryprogramcoordinateaxes(coordinateaxesrelativetowhichrotation,inclinationandshiftaredefinedarbitrarilytobedefinedfortheworkpiececoordinatesystem.Ifmachiningoperationsareprogrammedoncoordinateplanesrelativetothecoordinateaxesthusdefined,thecoordinatesareautomaticallyconvertedtomachinecoordinates.Thisisaveryusefulfunctionusedmainlyforsimultaneousthree-axismachiningcarriedoutusingauniversalattachment.Whenthisfunctionisused,itisveryimportanttoknowthepositionofthetipofthecutter.Thisismadepossiblebyaccuratetoopresettinganduseofacalibrationsystem(Photo4)Thisfunctionhasmadethemillingofoutsideflangesurfacesandthedrillingofholespossiblewithoutchangingequipmentormakingsetupchanges.Setup-andalignment-relatedfactorscontributingtoinaccuraciesinherentinmachiningoperationsperformedonahorizontalmachiningcenter,suchasdeflectionoftheworkpiecesetuponthetableanddeviationofthecentralaxisofrotarytablerotation,havealsobeeneliminated.Sinceafive-facemachiningcenterpermitsconsistentlyaccuratepositioningwithinthemachiningenvelope,accuracyofmachinedpartscanbeenhanced.3)FinishcontouringoflargeholeswithasidecutterAnotherchallengeinthemachiningoftheturbinecasingisthemachiningofinsidediameter(ID)grooves.TheturbinecasinghasmanyIDringgroovesthatneedtobemachined.TheconventionmachiningmethodistoassemblethetwohalvesofthesplitcasingandperformIDmachiningoftheassembledsplitcasingonalargeturninglathe.OntheHF-8M,eachofthetwohalvesofthesplitcasingwassetuponthetable(withthematingsurfacingupward)asshowninPhoto5,andfinishcontouringwascarriedoutwithacombinationofasidecutterattachmentandahigh-performancesidecutter.Toachievehighroundnessaccuracy,thefollowingmeasuresweretaken:(1)FiveadjustmentforhighmachineaccuracyThemaximuminsidediameteroftheworkpieceisabout3,500mm,anditsroundnesstoleranceis0.05mm.WhenperformingIDmachiningonalargemachinetool,itisverydifficulttoachievearoundnessof0.05mmonaninsidediameterexceeding3,000mm.Priortomachining,weinspectedtheaccuracyofthemachineandadjustedthepositioningaccuracyofX-YY-ZandX-Zplanes.Wealsofine-adjustedroundnesswithaDBB*systemtoenhancemachineaccuracy.Asaresult,wewereabletoachieveapost-machiningroundnessof0.04mm,whichwaswithinthetolerancerange.(2)Developmentofsmall-headtypesidecutterattachmentandhigh-performancesidecutter.Circularmachiningwithasidecutterisnotadvantageousifthegoalishigh-speedmachining.Thisisbecausecutterdiameter,groovecurvatureandgrooveconfigurationarerestrictedbythesizeandlengthoftheattachmenthead(spindleunit).Torealizehigh-speedmachining,therefore,ashortattachmentwithasmall