FMEA在生产管理质量中的作用(英文版)(ppt 44页)英文版.ppt

,FMEASteps,1DefinethescopefortheFMEA2Identifyteammembers,customer,andknowledgeexperts3Developrolesandresponsibilitiesforteammembers4Studytheproduct/process/service5DevelopratingscalesforSeverity,Occurrence,andDetection6Brainstormfailuremodes,knownandpotential7Listtheeffects,causes,andcurrentcontrolsforeachfailuremode8AssignratingsforSeverity,Occurrence,andDetection9CalculateRPN10DecideonathresholdRPN11PrioritizebasedonRPNandseverity,orasrequiredbythecustomer12Identifycorrectiveactions13Implementandverifyeffectivenessofcorrectiveaction14Completethedocumentation,1DefinethescopefortheFMEADefinetheboundarieswithinwhichtheproduct,process,orservicewillbestudied,identifyingtheoperatingassumptions,currentconditions,andconstraintsifany.Example1:ConductaProcessFMEAonPCBmanufacturingline1,startingwithoperation10andendingwithoperation250.Theassumptionisthatdesignofpartsiscorrect,andnoshortagesThelineissetupasshowninprocessflowdrawing#809901Example2:ConductDesignFMEAonthepressurereliefvalve(Part#JJJKKK)forpotentialfailuresunderextremeoperatingconditionsAssumenopreventivemaintenancewillbeconductedonceinstalledDocumentontheFMEAstartupform,FMEA;StepbyStep,ScopeoftheFMEA,Pointstoconsider:WhoarethecustomersfortheFMEA,andwhataretheirrequirements/expectationsExample:Conduct(Process)FMEAontheassemblylineforProductA,coveringoperations110through230WhenwillthisFMEAbeconsideredcompleteunderthegivenconditions(Remember,FMEAsareconsideredlivingdocuments,assuchtheyneedtobeupdated/revisedasthingschange.)Example:FMEAwillbeconsideredcompletewhentheteamhasimplementedallcorrectiveactionsasagreeduponbasedontheRPNthreshold,ThiswillformthebasisfordecidingthelevelatwhichyoushouldconducttheFMEA,andthescopeofworkinvolved.,LevelFocusFailureCauseEffectModeSystemCarOverheatingCoolingsyst.StrandedonfailuretheroadSubSystemCoolingSystemInadequateThermostatCarOverheatingcoolantflowstuckclosedSubAssemblyThermostatStuckclosedBiMetalSpringInadequatebrokencoolantflowComponentBiMetalSpringBrokenFatigueThermostatstuckclosed,Important:Youmustbeabletoseeacascadingoffailuremodes,causes,andeffectssimilartoabove,TheInfluenceofLevel,CompanyPlant1Plant2Plant3Plant4,PCBLinePowerSuppliesFHPMotors,Op10Op20.Op250,FMEAcanbeconductedatanyoftheselevels;italldependsonyourobjective,TheInfluenceofLevel,LevelFocusFailureCauseEffectModeSystemFactory(Plant2)LatedeliveriesLowFPYLosttocustomeronLine2businessSubSystemLine2(PowerSupplies)LowFPYHighReworkLatedeliveriesat/aftertestingOperationTestingHighreworkTestingresultsLowFPYOp210inconsistent,ExampleofaProcess,Op120,OpA20,OpA10,Op10,Op210,Op240,Op250,Important:Youmustbeabletoseeacascadingoffailuremodes,causes,andeffectssimilartoabove,TheInfluenceofLevel,2Identifyteammembers,customer,andknowledgeexpert/sGettheteamtogether,identifythecustomerandinvolvethemintheprocess.Somepreliminaryworkmustbedonetounderstandtheproduct/process/service,sotherightteamcanbeassembled.Example:TeammembersincludeJohnPatton,KiritChawla(Customerrep)KimHeaston,andBettyChung(TeamLead)Nooneknowsenoughabouttheprocessatthistime.DocumentontheFMEAstartupform,FMEA-StepbyStep,3DeveloprolesandresponsibilitiesforteammembersWhodoeswhatintheteam.Clearlydefinetherolesandresponsibilitiesforeachoftheteammembers.Atthistime,itisimportanttoconsiderthestrengthsofeachindividualandleveragethesame.Example:TeamLead:Coordinatetheactivitiesoftheteam,andkeepontrackActascheerleader,andinterfacewithmanagementEnsurethedecisionsaremadewithconsensusCustomer:DefinerequirementsParticipateindevelopingratingscales,especiallyforSeverityKnowledgeExpert:Asconsultantprovideinfoondetailsofproduct/processorservice,FMEA-StepbyStep,4StudytheProduct/Process/ServiceTheobjectiveofthisstepistoacquireasmuchknowledgeaspossible.Itishighlyrecommendedthatallteammembersdelveintothis,sincethereisnootherwaytofamiliarizeyourselfwiththeproduct/process/service.Example1:TheteamresponsibleforconductingProcessFMEAongaspanelsproductionlinespends2weeksonthelinebuildinggaspanels,andtestingthesame.Example2:TheFMEAteamresponsibleforDesignFMEAonamedicalimplantstudiesthewaytheproductisgoingtobehandledintheoperatingroom,andusedbythesurgeon.Example3:FouroutoffivemembersoftheFMEAteamspend3dayswiththephoneoperators,andorderprocessinggrouptogetfirsthandunderstandingofallthestepsinvolvedinbookinghotelrooms.,FMEA-StepbyStep,5DevelopratingscalesforSeverity,Occurrence,andDetectionOnceyouhavegainedenoughknowledgeabouttheproduct/process/serviceandaboutthewayitmaybeusedbythecustomer/enduser,youareinapositiontodevelopmeaningfulratingscales.Mostratingscalesareonascalefrom1to10,howeversomemayusea1to5scale.Whichofthetwo,islessimportantthanensuringthatthesamescaleisusedthroughoutthecompany.Youmayhavetodevelop/adaptthescalestosuityourneedsForexamples,seenextpage,FMEA-StepbyStep,CausesFailureModes*EffectsOccurrenceDetectionSeverity,Howfrequent?Whohasthemostinfo?Ifeliminated,willfailurebeavoided?,Howeasytodetectwithcurrentcontrols?Whohasthemostinfo?Ifpreventedwilleffectsbeeliminated?,Howsevere?Whohasthemostinfo?,QuantifyingFailureModes,EffectsandCauses,*CausesmaybeusedinplaceofFailureModesinsomecases,5DevelopratingscalesforSeverity,Occurrence,andDetectionExamplefromDesignFMEA:,SeverityOccurrenceDetectionEffectCauseFailureModeorCause,1Remotechance,=200foreachfailuremode:,FMEA-StepbyStep,11PrioritizebasedonRPNandseverity,orasrequiredbycustomerArriveattheorderinwhichyouwillstartaddressingthefailuremodesandcausesforcorrectiveaction.AlthoughRPNandseveritybasedprioritizationseemsthemostlogical,yourdecisiontoproceedmustbemadewithcustomerinput.Thisstepiseasilyaccomplishedbysortingthedata,indescendingorder.Youcandothiswithineachfailuremodetomaintaindataintegrity.Documentationonworksheetisimportanttoensurethewholeteamisinsync.,FMEA-StepbyStep,11PrioritizebasedonRPNandseverity,orasrequiredbycustomerExampleofsortedworksheetbyRPNwithineachfailuremode,FMEA-StepbyStep,12IdentifycorrectiveactionInthisstepyouidentifythecorrectiveactionsneededtoeliminate/controlthecauses,andreducetheriskleveltoorbelowtheagreeduponthreshold.Therewillbetimeswhenyoucannotworkontherootcause;insuchcasesthebestcourseofactionwillbeviaadditionofcontrols/adequatewarningdevices/mechanismsofimpendingfailure.Re-evaluatetheratingsforS,O,andD,followedbyRPNcalculation.Discussionwiththecustomerisimportantagainsincethecorrectiveactionswillimpactthem.Knowledgeexpertsmayalsoprovidevaluableinputastowhatkindsofcorrectiveactionwillbebestsuitedforthegivencause/failuremode.Finally,fromallpossiblecorrectiveactions,theteammaychooseonebasedoncost/benefitanalysis,speedofimplementation,andthenewlevelofrisk.,FMEA-StepbyStep,12IdentifycorrectiveactionExample-allcauseswithRPN=200areaddressed:,FMEA-StepbyStep,12IdentifycorrectiveactionQuestions:Whydidthecauseofworntireshaveanactionitem,althoughtheRPNwas160?TraininginadvanceddrivingtechniquesreducestheRPNfrom350to200,shouldheteamstophere?Whyisitthattheseverityratingdoesnotreducealthoughtraininginadvanceddrivingtechniquesisprovided?Doyouthinktheteamsworkisdone?,13ImplementandverifytheeffectivenessofcorrectiveactionCorrectiveactionsidentifiedoughttobeimplementedlikeprojects-withadefinitestartandend.Inmanycasesaprojectteamsmaybeformedtocarryouttheimplementation.TheseprojectteamsmayhavemembersfromoutsidetheFMEAteam,howeveratleastonemembershouldbedrawnfromtheFMEAteam.Acheckontheeffectivenessofthecorrectiveactionisimportant,intheabsenceofwhichyouwillnothaveaclosedloopfeedbackonwhatreallytranspired.ThischeckshouldbeconductedbytheFMEAteamafterthecorrectiveactionshavebeeninplaceforsometime.Thisissobecausethecorrectiveaction,likeachange,maynotlast.Ittakesdiligentefforttoensurethechangewillhavepermanence.Ifthecorrectiveactionisnoteffectiveenough,youmayneedtoimplementsomemorecontrols/takemoreactions.,13ImplementandverifytheeffectivenessofcorrectiveactionExampleofadditionalactiontakentoreduceriskfromdrivinghabits:,14Completethedocumentationandsaveinarchives/databasesThislaststepisoverlookedbymanyoftheFMEAteams.Whileitisunderstandablethatthenextprojectneedstobeworkedon,itisalsoimportantnottolosetheknowledgegainedbytheteam.Thebestwaytodocumentistousearchivingsystemsinthecompanyiftheyexist,electronicstorageisnowacceptedbymostregulatoryagenciesnow.Itemsthatshouldbesavedinclude:FMEAstartupformFMEAworksheetsMeetingminutesProcessflowDesignspecs,andvoiceofcustomerDetailsofprojectscreatedandimplementedaspartofactionitems,PortablesCosmeticProcessFMEAResults,Area:,PortablesMod8,DateCompleted:,1/5/98,TeamMembers:,BabakShahmehri,BrendaTurner,DickHolcomb,ScottWise,ActionCriteria:,FailureCauseswithRPNNumbersof40orHigher,Findings:,AreaFound:,FailureCauses:,RPN#,Actions:,AssignedTo:,Notes:,1,Wipedown,Rejectingallunitsforany,defectsdueto,lackof,trainingoncosmetic,standards,therebycausing,delayedordersandhigher,unitcosts,60,Easytouse,operator-friendly,criteria(pictures/overlays),costof,cosmeticdefectrepairstudy,more,definedandup-to-datespecs,QualityEngineering,Production,2,Wipedown,Rejectingallunitsforany,defectsdueto,hardtofollow,cosmeticstandards,therebycausingdelayed,ordersandhigherunitcosts,60,Easytouse,operator-friendly,criteria(pictures/overlays),costof,cosmeticd