汽車專業(yè)畢業(yè)設計-翻譯-中英文(全)lean-remanufacture-of-an-automobile-clutch

PAGEXXXLeanRemanufactureofanAutomobileClutch TonyAmezquita* AssistantProfessor,correspondingauthor. and BertBras*** AssistantProfessor,correspondingauthor.** RemanufacturingEngineer. SaturnCorporation SystemsRealizationLaboratory SpringHill,Tennessee Woodruff GeorgiaInstituteofTechnology Atlanta,AbstractInthehistoryofmanufacturingtherehavebeenthreeproductionsystems,namely,craftproduction,massproduction,andleanproduction.Inmanyautomotiveremanufacturingoperations,craftproductionandmassproductionsystemsareusedasthebasisforremanufacturingprocesses.Theleanproductionsystemhasproventobemoreeffectiveinthemanufactureofautomotivepartsandithasallowedmanufacturerswhouseittoproduceinmuchgreatervarieties,withhigherqualitylevels,andwithlowercosts.Hence,ifusedinremanufacturing,itwouldgreatlyenhanceit.Inthispaper,acurrentremanufacturingprocessofanautomobileclutchisanalyzed,andaleanremanufacturingprocessisdevelopedandcomparedtotheasisprocess.Ourfindingsindicatethattheleanremanufacturingprocessprovidesamorerobustprocesswithlowercostswhencomparedwiththecurrentclutchremanufacturingprocessthatutilizecraftandmassproductionpractices.

1 OurFrameofReference–RemanufactureintheAutomotiveIndustryRemanufacturingisthemosteconomicallysustainableformofreuseandrecyclingofmanufacturedgoods,anditcanbedefinedastheindustrialprocesswherewornoutproductsreferredtoascores,arebroughtbacktooriginalspecificationsandcondition.Insomecases,especiallyintheremanufactureofOEMautomotiveparts,remanufacturedproductsexceedoriginalspecifications.Thereasonisthatthelatestengineeringdesignandspecifications,coupledwithfailuremodecountermeasuresderivedfromfailureanalysis,areusedinsteadoftheoriginalspecifications.Thebenefitsofremanufacturingaremany,butthemostsalientare:1) Remanufacturingsalvagesthematerial,energy,capital,labor,andemissionsthatwentintothemanufactureandmaterialprocessingofproducts.2)Theresultingproductioncostscanoftenbelowerthanmanufacturing,allowingremanufacturerstoselltheirunitsfor25to50%lessthanmanufacturedunitswithequivalentorbetterqualitylevels.Thesetwobenefitsaretheresultofthefactthatpartsarereusedandtheembeddedutilityinthepartsaremaintained.Hencetheresultingproductioncosts,whichshouldbeconsiderablylessthaninmanufacturing,allowremanufacturerstopassthesavingsontoconsumers.Remanufacturingintheautomotiveindustrycanbedividedintotwogroups;independentremanufacturersandOriginalEquipmentManufacturer(OEM)remanufacturers.BothoftheseactivitiesinthedomainofautomotiveproductsconstitutethelargestremanufacturingconsumermarketsegmentintheUnitedStatesandEurope.In1978,KuttaandLunddocumentedasurveycapturingsomeoftheissuesimportanttoremanufacturersADDINENRef(KuttaandLund,1978).However,wediscoveredinsurveysandinterviewswithremanufacturersthatmanychangeshaveoccurredintheindustrysincethenADDINENRef(Hammond,etal.,1996,Hammond,1996).Majorchangeshavebeentherestructuringofautomotivecompaniesintoplatformsandthetrendtowardsmasscustomizationofproducts.Especiallythelatterhasresultedinwhatremanufacturershavetermed“PartsProliferation”,whichreferstothepracticeofmakingmanyvariationsofthesameproduct-differingonlyinoneortwominorareas.However,thesedifferences(suchaselectricalconnectors)aredistinctenoughtopreventinterchangingthesesimilarproducts.Thefocusinthispaperisonindependentautomotiveremanufacturers,becausetheyremanufacturecomponentpartsfrommostoftheautomobilemanufacturersintheworld,andforaverylargenumberofmodelyears.Thisbeingthecase,independentremanufacturersarefacedwithapartsproliferationproblemwhichcannotbesuccessfullyhandledwiththeircurrentproductionpractices,thatconsistofamixtureofmassproductionandcraftproductionpractices.Asdescribedbelowcraftproductionpracticesmaintainproductioncostshighregardlessofvolume,andmassproductionpracticesarenotcompatiblewithlargeproductvarieties.Consequentlyindependentpartsremanufacturersareloosingmarketsharetoaftermarketpartsmanufacturers,andinsomecases,remanufacturersarebeingforcedoutofthemarket,asinthecaseofclutchremanufacturing.Forexample,in1989thepricedifferencebetweenremanufacturedandmanufacturedclutcheswas50%.In1994thedifferencedroppedto20%,andnowalargenumberofclutchremanufacturersaregettingoutofclutchremanufacturingaltogetherADDIN.Itisourbeliefthatthetrendsinmasscustomizationandpartsproliferationwillnotdecreaseandthesmalltomediumsizedindependentremanufacturersseemtosuffermostfromthesetrends.Oursurveysalsopointoutthedifferencesandsometimeshard“usversusthem”attitudebetweenindependentremanufacturersandOriginalEquipmentManufacturers(OEMs),leadingustobelievethatthesharingofdesigninformationbetweenOEMandremanufacturerisnotafeasiblesolutionand/oroptioninmanycases.Hence,theonlywaywecanhelpincreasetheremanufacturabilityofthoseproductsisbyimprovingtheremanufacturingprocesses.Inthispaper,wepresentsomeofourfindingswhich,interestinglyenough,indicatethattheintroductionofleanproductiontechniques(whichareoneofthemaincausesofpartproliferationandproductdiversity)intheremanufacturingindustry,andhencecreatingleanremanufacturingprocesses,canleadtosignificantprocessimprovementsandsavingsADDINcomparedtothecurrentremanufacturingprocesseswhichareheavilybatchoriented.Inthispaper,asolutiontothepartsproliferationproblemofindependentautomobilepartsremanufacturersisdevelopedbytransformingacurrentremanufacturingprocessofanautomobileclutchintoaleanremanufacturingprocess.ThisleanclutchremanufacturingprocesshasbeendevelopedingreatdetailinADDINENRef(Amezquita,1996).Inthispaper,wewilldiscusstheas-isprocess,followedbyadiscussiononhowtoconvertthisprocessintoaleanremanufacturingprocess.Itshouldbestatedup-frontthatalthoughtheproposedleanprocessofferssubstantialsavings,ithasnotbeenimplementedbythecompanywhosupportedthiscasestudy.First,however,wewillprovidethenecessarybackgroundoncraft,mass,andleanproductionsystems.2 Craft,Mass,andLeanProductionInthe1800s,automobilemanufacturingwasthedomainoftheskilledcraftsmenwhocontrolledmostoftheactivitiesonthemanufacturingfloor.Theseskilledcraftsmendesignedandbuiltcustomizedvehiclesbymakingandfittingeachpartbyfilingitdownuntilitmatedwiththeothervehicleparts.Evenifcraftproducerscouldmake10,000identicalcars,thepricepercarwouldnothavedroppedbymuch,becauseeachcarwasessentiallyaprototype.Thebiggestbenefitsofthiscraftproductionsystemintheautomotiveindustrywerethat:? customerswereabletoobtainproductswhichspecificallymettheirneeds,and? workersweresatisfied,proud,andfulfilled,andtheirgoalwastohoneandperfecttheirskillsandonedaybecomeindependentowners.Attheturnofthecentury,FrederickTaylorremovedthecontrolofthemanufacturingoperationsfromthehandsoftheskilledcraftsmenbycreatingdivisionsoflabor.Thiswasthefirststeptowardsthedevelopmentofmassproduction,whichwasfullyimplementedbyHenryFord.TakingthedevelopmentsofTaylor,Fordaddedthestandardizationoftheproductionofparts,whichledtocompletepartsinterchangeability,whichinturnledtothesimplificationofpartsassembly.In1908,anassemblerwasspending514minutes(8.56hours)assemblingalargeportionofthecarbeforemovingtothenextcarADDINENRef(Womack,etal.,1991)ADDIN.Toreducethecycletimeofassemblers(periodoftimespentwitheachvehiclebyeachemployee),Fordhadeachassemblerperformasingletaskandmovefromvehicletovehicleintheassemblyhall.Thecycletimepervehiclewasreducedfrom8.56hoursto2.3minutesADDINENRef(Womack,etal.,1991)!Finally,thesimplificationofassemblytasksallowedFordtoutilizethemovingassemblylinetobringthecarstotheassemblersandeliminateallthewalkingpreviouslydone.Inaddition,themovingassemblylineenforcedafasterandevenworkpace.Ford’simplementationofthemovingassemblyline,whichbroughtthecarpastthestationaryworker,cutcycletimeevenfurtherfrom2.3minutesto1.19minutesADDINENRef(Womack,etal.,1991).Forddiscoveredthathisnewsystemreducedtheamountofhumaneffortneededtoassembleavehicle,andwiththesamenumberofpeople,equipment,etc.,themorestandardizedvehiclesheproduced,themorethecostpervehicledropped(economiesofscale).BythetimeFordreachedvolumesoftwomillionidenticalvehiclesperyear,hehadslashedtherealcosttotheconsumerbyanadditionaltwothirdsfromthetimehestartedproductionoftheModelTin1908.Consequently,aproductionsystemwhichmostcloselyresemblesthemassproductionsystemcanbringsubstantialsavingstoaremanufacturer,andisoftenadvocated.However,thissystemrunsagroundwhenconfrontedwithalargevarietyofparts,whichisthecurrentsituationmanyindependentautomotiveremanufacturersarefacing.Mostautomotivepartsremanufacturers(andotherremanufacturers)stillrelyoncraftproductionsystemstohandlethevariabilityinthenumberofpartstoberemanufacturedandthevariabilityinherentinrefurbishingoperationsduetoweardifferences.However,asnotedalreadybyHenryFord,craftproductionsystemhastwomaindrawbacks:1) Productioncostsremainhighregardlessofvolume(economiesofscalearenotpossible,e.g.FerrariAutomobiles).2) Quality,consistency,andreliabilityarepoorduetothelackofstandardization.Thus,adifferentapproachtoremanufacturingwhichuseselementsofthemassandcraftproductionsystemsmayprovetobemoresuitableforautomotivepartsremanufacturing.Leanproductiontakesthebestelementsofthecraftandmassproductionsystems.ThissystemwasdevelopedbytheToyotaMotorsCorporation,andlateriswasimplementedbyallJapaneseautomotivemanufacturers.Leanproductioncanbedefinedasanentireproductionsystemwiththefollowingfundamentalcharacteristics:1) Economiesofscale(frommassproduction),2) Productionoflargevarietiesofproducts(fromcraftproduction),3) Eliminationofnon-valueaddedresourcesandactivities,and4) Integrationofallproductionsystemelementsandfunctionstoobtainlongtermfunctionalrelationships.Comparedtotheleanproductionsystem,thetraditionalmassproductionsystemcanbefundamentallydefinedashavingthefollowingcharacteristics:1) Economiesofscale,2) Verylimitedrangeofproductvarieties,3) Non-valueaddedresourcesandactivitiesareperceivedasnecessary,and4) Divisionofallproductionsystemelementsandfunctionstoobtainspecializationresultinginshorttermstrainedrelationships.Giventhefactthattheleanproductionsystemismostsuitablefortheproductionoflargevarietiesofproducts,anditallowstheattainmentofeconomiesofscale,itwouldseemthatusingthisproductionsystemasabasisforremanufacturingprocesseswouldprovidebetterresultsthantheonescurrentlyobtained,whichareforcingindependentpartsremanufacturersawayfromremanufacturing.Intheremainderofthispapertheremanufacturingprocessofanautomobileclutchatoneofthelargestindependentautomotivepartsremanufacturersisusedasacasestudy.3 AutomobileClutchRemanufacturingatRaylocTheRaylocCompanyisadivisionoftheGenuinePartsCompanywhichprovidesaftermarketreplacementpartsat6,500NAPAAutoPartsstoresnationwide.Raylocisoneofthelargestautomotivepartsremanufacturersintheworld,andtheyremanufacturepartssuchasalternators,starters,driveshafts,brakemastercylinders,calipers,wipermotors,windowliftmotors,rackandpinionunits,steeringboxes,powersteeringpumps,brakeshoes,discbrakesandclutches.Thefocusofthispaperisplacedontheremanufacturingprocessofclutches.TheclutchremanufacturingprocessatRaylocwasanalyzedforsixmonthsatoneoftheremanufacturingplants.TheprocessmaterialflowisrepresentedschematicallyinFigure1.Figure1-CurrentClutchRemanufacturingProcessMaterialFlowWithBatchingInthisprocesscoresaresuppliedbycustomers,andareaccumulatedrandomlyindrumswithoutidentificationattheNAPAjobbersorretailers.Cores(c1,c2,etc.,seeFigure1)arethenidentifiedandsortedbypartnumberandmanufacturer,andareagainaccumulatedinacorewarehouseattheRaylocplant.Basedonaforecast,coresareremovedfromacorewarehouseandprocessedinabatch.Batchesofthesamepartnumberarerandomlymixedandthereusablecomponentsareassembledtogetherwithreplacementcomponentparts.Non-reusablecomponentsarerecycledafterworkhasbeendoneonthem.Theremanufacturedcores(rc1,rc2,etc.,seeFigure1)areplacedinafinishedgoodswarehousetostartthecycleoveragainafteracustomerbuystheremanufacturedclutch.Theassumptionbehindthisremanufacturingprocessisthatidenticalcorescanbeeasilycollectedintoeconomicbatchesandtogethertheycanbedisassembled,cleaned,inspected,refurbished,andreassembled.Theprocessisdistinguishedbyhavinglargeenoughvolumestoobtainsomeformofeconomiesofscale.Thepracticeofbatchinginremanufacturingwasadoptedfrommassproduction,butbatchingisalsodoneinremanufacturingforthepurposeofcannibalizingreusablepartsandreducetheneedtopurchasenewmanufacturedreplacementparts.Purchasingmanufacturedreplacementcomponentsisforthemostpartmoreexpensivethancannibalizingcores.Infact,afundamentalprincipleofeconomicremanufacturingisthemaximizationthereusedcontentinfinishedremanufacturedproducts.Afterthecompletionofthestudy,theclutchremanufacturingprocesswascharacterizedusingthecriteriaasshowninTable1.Thecharacteristicsofthisprocessreflecttheproblemsandissuesindependentautopartsremanufacturersface,andarenotindicatorsthatRaylocispoorlyrun.Infact,RaylocisoneofthemostefficientremanufacturersintheU.S.A.withaproventrackrecordexemplifiedbythefactthatRayloc’sremanufacturedclutchesarestillsellingwell,inatimewhenotherremanufacturers’clutchesarebeingphasedoutfromthemarket.Table1-SummaryofCurrentCharacteristicsofClutchRemanufacturingProcessCriteriaCurrentConditionsCriteriaCurrentConditionsAverageDirectLaborRequirements43MaintenancePersonnelRequirementsLowDailyAverageOutputperEmployee9.6Units(413/43)MachineInvestmentvs.ManufacturingLowPartsTransportationDistances1759feetProcessEngineeringMinimalProcessingLeadTimes≤21daysDirectLaborSkillsHighCoreReplacementPartsNeeded(“New”andCannibalized)Diaphragms,Straps,Rivets,PressurePlates,Facings,ShimsIn-ProcessCoreDamageHighProcessCycleTime255minutesHazardousResidueStreams3BatchSizes10≤Bs≤200(avg.Bs=120)ProductDesignChangesAdaptabilityLowAverageSetupTimes42minutesCustomerServiceLevelsLowQuality&ReliabilityLevelsLowerthanclutchmanufacturingFinishedGoodsWarehouseCostsVeryHighTherelativelylongprocessingleadtimerequirestheuseofawarehousetobufferthefactoryfromthemarket.Whenproductvarietiesaresmall,thisapproachdoesnotrequiretheneedtostorealargequantityofparts,aswasoncethecaseinthe1960satRayloc,whenremanufacturedproductswhereshippeddirectlyfromtheremanufacturingprocessADDINENRef(LeCour,1996)ADDIN.Butwhenvarietiesarelarge,inventorylevelsinthewarehouseincreaseconsiderably,andcustomerservicelevelsdrop.4 DesigningaLeanProcessforAutomobileClutchRemanufacturingAleanremanufacturingprocessmusthavethefollowingelementsasstatedearlier:1) Economiesofscale(frommassproduction),2) Productionoflargevarietiesofproducts(fromcraftproduction),3) Eliminationofnon-valueaddedresourcesandactivities,and4) Integrationofallproductionsystemelementsandfunctionstoobtainlongtermfunctionalrelationships.Inthefollowingsections,wepresenthowtheseelementscanbeachievedfortheRaylocclutchremanufacturingprocess.4.1 ObtainingEconomiesofScaleandtheAbilitytoHandleLargeVarietiesofProductsInordertoobtaineconomiesofscale,onemustdowhatHenryForddid:standardize.However,intraditionalremanufacturingprocessesitisverydifficulttostandardizebecauseofthe“stochasticnatureofboththeamountofworkandtheroutingsrequiredtorebuildaunit”ADDINENRef(Guide,1996)ADDIN.Thisargumentisapplicableintheremanufacturingshopwhichutilizesajobshoplayoutandtheworkisperformedinamannerconsistentwiththecraftproductionsystem.Thus,thefirststepinobtainingaleanremanufacturingoperationistomoveawayfromcraftproductionor“artisanwork”andcreateastandardizedprocess.Thishowever,cannotbedoneinthesamefashionForddid.Atthebeginningofthecentury,Fordreliedonhardautomationtostandardizetheproductionwork,andthuseliminatingadjustments,incontrasttocraftproductionwheremulti-purposemachinesrequirevariousadjustmentswhichrequireskilledcraftsmen.Fordhadstandardizedallthetoolingandtaskssowellthathepracticallyeliminatedalladjustments.Thepenaltywiththissystemwasthathehadnoflexibilitytoswitchbetweenmodelswiththesamemachinery.WhenFordredesignedtheModelA,hediscardedthemachineryalongwiththeoldmodelADDINENRef(Womack,etal.,1991).Toobtainstandardizationandeliminateadjustments,butstillmaintaintheflexibilitytohandlealargevarietyofpartsormodels,flexibleorprogrammableautomationisneededinamodernprocess.ProgrammableautomationhastraditionallyhadthefollowingfeaturesADDINENRef(Chang,etal.,1991)ADDIN:1) Highinitialinvestment2) Highcomplexity3) HighprogrammingcostsInthispaper,theconceptofLeanMachinesisdevelopedforthepurposeofcounteractingtheabovementioneddrawbacksofprogrammableautomation.TheconceptofLeanMachinesisderivedfromtheNagarasystem,whichisarecentdevelopmentofleanproductiontofurtherreduceleadtimesandeliminatewaste.Thebiggestaccomplishmentofthisdevelopmentistheobliterationofboundariesbetweendepartments.Inotherwords,thisdevelopmentallowsforacomprehensiveandcoherentone-piece-flow,withouttheneedtotransportpartstothepaintdepartment,stampingdepartment,thecleaningdepartment,etc.AproductionexampleillustratestheconceptoftheNagaraSystem.“Aftermachinesperformthedrillingandtappingontheline,partsareplacedinone-metercubicalboxthatis,infact,adeviceforspray-paintingparts.Closingthelidoftheboxtripsaswitchandsetstheoperationinmotion.Smallfittingsandwiresareattachedtothepartsinaone-pieceflowaftertheyareremovedfromthebox.Morethanonehundredoftheseboxeshavebeenintegratedintoprocessingandassemblylines.Thishaseliminatedapproximately80percentofthepaintingwhichearlierrequiredmovingpartstothepaintingshop”ADDINENRef(Shingo,1989).Thus,LeanMachinesaresimple,small,andautomaticmachineswhichcanbedesignedandbuiltwithasmallbudget.Inorderformachinestocycleautomatically,theymusthavesomeformofcontroller.Ford’sdedicatedmachines,werecontrolledwiththeuseofmechanicalmechanismssuchascams,governors,ways,slides,andpistonsADDINENRef(Chang,etal.,1991)ADDIN.Thistypeofcontrolisthemostdifficulttomodify.Themostversatilecontrolisprovidedwithdigitalcontrollers,becausethecontrollogicisprogrammedintothecontrollermemoryusingsoftware.LeanMachinesmakeitpossibletostandardizetheworkdonewithmachines,whileatthesametimeprocessalargevarietyofpartnumbers.Thus,LeanMachinesdifferfromFord’smachinesinthattheyallowconsiderableadjustments,butaresimilartoFord’smachinesinthattheadjustmentsarestandardizedorsavedinaprogrammablememory.Bybeingabletocapturetheknowledgeofmanycraftsmeninthememoryofthemachines,allthetaskspreviouslyperformedbycraftsmen,includingsetups,canbestoredandrecalledasdictatedbycustomerorders.Thus,the“wheeldoesnotneedtobereinvented”everytimeadifferentpartnumberisremanufactured.AnexampleofaLeanMachineispresentedherewiththeuseoftheassemblyoperationshowninFigure2.WithaLeanMachinesetuptimesforthisassemblyoperationcanbereducedfromanaverageof42minutestoseconds,inbigpartduetotheeliminationofadjustments.Figure2-RivetingtheDiaphragmtotheClutchCoverDuringasetupchange,thestepsgiveninTable2areperformed.Table2-“RivetingDiaphragmtoCover”SetupElementsandTimesSetupElementsMinutes1.putawaycomponents6.912.obtaincomponents8.393.lookuppartnumberinfoinbook1.234.putawayfixture1.455.findnewfixture1.776.adjustmachine20.247.completedcover2.53Toreducethesetuptimesfrom42minutestoseconds,thefirststepistoeliminatetheuseofintuitionandskilltoadjustthemachine(element#6)and“reinventionofthewheel”.ThecurrentmachineadjustmentsrequiredduringthesetupareillustratedinFigure3.Figure3-AdjustmentsRequiredtoSetup“RivetingDiaphragmtoCover”O(jiān)perationTheadjustmentofthepunchthatpressestherivetsdownrequiresthattwoboltsbeloosened,andthepunchbeplacedexactlyinmiddleofoneoftheninefixtureindentationswheretherivetsareplaced.Thefixtureindentationsprovidetheoperatorwithanexactlocationwheretherivetsmustbeplaced.Thispunchadjustmentmustbedonebytrialanderror,becausethereisnoreferencepointthatcanbeusedtoguidetheadjustmentofthepunchrelativetothefixture.Butbeforethepunchcanbeplacedinthecorrectlocation,oneofthefixtureindentationshastobelineduptothepunch.ThreeAllenheadscrewsareusedtoholdthefixturebaseinplace,andeverytimethefixtureneedstobeadjusted,thethreescrewsneedtobeloosedandtightenedagain.Themostdifficultpartofthesetupforthismachineisthatasoneofthereferencesismoved,suchasthepunch,thefixturemustalsobemoved.Onceanadequateadjustmentappearstohavebeenmade,testswithrivetsmustbeperformedtocheckthesetup.Manytimesthepositionofthepunchrelativetothefixtureisnotprecise,butittakessomuchtimetopositionthetwoelementspreciselycenteredrelativetoeachother,thattheoperatorschoosetostartprocessingpartsandpunchrivetsoff-center.Thispracticedeterioratestheappearanceofthecover.Asolutiontothesetupproblemistostandardizethesettingsbystoringtheminprogrammablememoryandusingamodified3-JawChuckfixturewithninelocatorpinsasshowninFigure4.Ninepinsareusedbecausemostautomotiveclutchesuseninerivetstoattachthediaphragmtotheclutchcover.Figure4-Usinga3-JawChuckastheBasisforaNinePinAssemblyFixtureThismechanismincludestheuseofsteppermotors,whichtaketheplaceofthechuckhandle,andadigitalmotioncontrollersystem.MotioncontrollersystemsusuallycontainabatterybackedRandomAccessMemory(RAM)thatcanstorevariousprogramswhenstand-alone.ARemotePanelOperatorInterface,whichisusuallyconnectedviaRS-232-CSerialCommunicationinterface,canbeusedbytheoperatortoenterthepartnumbertobeprocessedeachtime.Basedontheinputontheremotepanelandthealgorithmintheprogrammedmemory,motioncontrollers,throughthesteppermotordrivers,sendoutaseriesofelectricalpulsestothesteppermotorwhichcausethemotorstostepfractionsofrevolutionsorstepanglesandplacethelocatorpinsatstandardizedlocations.ThecompletemechanismisshowninFigure5.Thismechanism,whichcanbeplacedonasimplehydraulicpress,constitutesaLeanMachine.Figure5-MechanismtoStandardizeAssemblyFixtureSettingsElements#3,4and5ofthesetupoperationdepictedinTable2arealsoeliminatedwiththeuseofthisLeanMachine,sincetheinformationpertinenttothepartnumberisstoredinmemory,andfixturesdonotneedtobeexchanged.Tocompletelyreducethesetuptimeofthisoperationtoseconds,setupelements#1and2canbeeliminatedbystoringreplacementcomponentparts,suchasrivetsandshimsattheexactpointofuseandeasilyaccessible.Inaddition,workersdonotneedtogatherthecorecomponents,becausethesecomponentsarriveatthetimeneededfromup-streamoperations.Thusbyplacingthecomponentsatthepointofuse,andusingaleanmachinetostandardizethemachineadjustmentsneededtoprocessdifferentpartnumbers,setuptimesforthisoperationarereducedtoseconds.4.2 Eliminatingnon-valueaddedresourcesandactivitiesToremovenon-valueaddedresourcesandactivitiesfromaprocess,wemustunderstandwhattheseare.Inleanproductiontherearesixnon-valueaddedwastes,asshowninTable3.Table3-LeanProducersNon-ValueAddedWastesandCountermeasuresNon-ValueAddedWastesCountermeasureswasteofoverproductionmakeonlywhathasbeenorderedalreadywasteofwaitingkeepproductflowingandbatchesofsize=1wasteoftransportingplaceoperationsnexttoeachotherandstoreassemblypartsatthepointofusewasteofinventoriesmakeonlywhathasbeenorderedalreadywasteofmovingchangeworkingconditionstoeliminateunnecessarymovingwasteofdefectivepartsandproductspreventerrorsfrombecomingdefectsbyusingsourceinspectionsToeliminateorreducethewasteofoverproduction,aremanufacturingoperationmustonlymakewhathasbeenorderedalreadyinordertoeliminatetheneedtohaveafinishedgoodswarehouse,andallthestorageandhandlingcostsassociatedwithinventorymanagement.Thisisonlypossibleifthecompleteremanufacturingprocessisleanenoughtohaveproductionleadtime