失效模式及其影响分析研究报告课件

FailureModeandEffectAnalysis

失效模式及其影响分析1FailureModeandEffectAnalysModuleObjectives课程目的DescribeFMEAprinciplesandtechniques.描述FMEA的法则及技巧。Summarizetheconcepts,definitions,applicationoptionsandrelationshipswithothertools.摘要概念、定义、应用的选择和其他工具的关联。PerformaFMEA执行一个FMEA。2ModuleObjectives课程目的DescribeFMEA:FailureModesandEffectsAnalysisFMEAisasystematicapproachusedtoexaminepotentialfailuresandpreventtheiroccurrence.Itenhancesourabilitytopredictproblemsandprovidesasystemofranking,orprioritization,sothemostlikelyfailuremodescanbeaddressed. FMEA是用来检查潜在失效和预防它再次发生的系统性方法.它增强了我们预测问题的能力,并提供了一个排序或区分优先次序的系统,因而使得最可能的失效模式得以确定.FMEAisgenerallyappliedduringtheinitialstagesofaprocessorproductdesign.Brainstormingisusedtodeterminepotentialfailuremodes,theircauses,theirseverity,andtheirlikelihoodofoccurring.InSixSigma,weapplyFMEAtoknowfailuremodes.Ourmaininterestsarethecauseandlikelihoodofoccurrence,forwhichwehaveactualdataanddonotneedtorelyonbrainstorming.FMEA通常应用在工艺及产品设计的初期，自由讨论决定潜在失效的模式、原因、严重度及发生的可能性。在6S中，我们应用FMEA去了解失效的模式。我们主要感兴趣的是原因及发生的可能性。FMEAisalsoavaluabletoolformanagingtasksduringdefect/failurereductionprojects.FMEA也是一个在失效缩小的管理任务的有价值的工具。FMEA3FMEA:FailureModesandEffectDefinitionofFMEA定义recognizeandevaluate

thepotentialfailuremodesandcausesassociatedwiththedesigningandmanufacturingofanewproductorachangetoanexistingproduct.

认识和评估新产品的设计和制造时或对现有产品做出改变时相关的潜在失效模式和原因identify

actionswhichcouldeliminateorreducethechanceofthepotentialfailureoccurring,

确定消除或减少潜在失效发生机会的行动document

theprocess.

使过程形成文件FMEAisa

systematic

designevaluationprocedurewhosepurposeisto:是系统的设计评估程序4DefinitionofFMEA定义recognizeFailuretoperformadefinedfunction 执行既定功能的失效Somethingoccurringthatyoudon‘texpect,orwant 发生了你不希望或不想要的事情Wrongapplication

应用错误AFailureModeis...失效模式是……5FailuretoperformadefinedfFMEAUsebyBlack/Brown/GreenBeltsToidentifypotentialfailuremodesandratetheseverityoftheireffectsToidentifycriticalcharacteristicsandsignificantcharacteristicsTorankpotentialdesignandprocessdeficienciesTohelpallofusfocusoneliminatingproductandprocessconcernsandpreventproblemsfromrecurringReducetheproductdevelopmenttimingandcost6FMEAUsebyBlack/Brown/GrBackgroundDevelopedinearly60’sbyNASAto“fail-proof”Apollomissions.Adoptedinearly70’sbyUSNavy.Bylate80’s,automotiveindustryhadimplementedFMEAandbeganrequiringsuppliersdothesame.Liabilitycostswerethemaindrivingforce.Usedsporadicallythroughoutindustryduring1980’s.AdoptedbyMSIin?

SixSigmaisthecatalyst.7BackgroundDevelopedinearly6NASAusedFMEAtoidentifySinglePointFailuresonApolloproject(SPF=noredundancy&lossofmission).Howmanydidtheyfind?420andwethoughtwehadproblems!8NASAusedFMEAtoidentifySinTypesofFMEA’sSYSTEMDESIGNPROCESSSystemFMEAisusedtoanalyzesystemsandsubsystemsintheearlyconceptanddesignstages.DesignFMEAisusedtoanalyzeproductsbeforetheyarereleasedtoproductionProcessFMEAisusedtoanalyzemanufacturing,assemblyandadministrativeprocesses9TypesofFMEA’sSYSTEMDESIGNPRWhenistheFMEAStarted?“Dothebestyoucanwithwhatyouhave”ASEARLYASPOSSIBLE!Guideline:10WhenistheFMEAStarted?“DotWhentoStart???Whennewsystems,productsandprocessesarebeingdesignedWhenexistingdesignsandprocessesarebeingchangedWhencarry-overdesignsorprocesseswillbeusedinnewapplicationsorenvironmentsAftercompletingaProblemSolvingStudy,topreventrecurrenceofaproblem11WhentoStart???WhennewsystBeginningandEnd12BeginningandEnd12EffectofFMEAonProcessandDesignchangesDesignStartDevelopmentProductionReleaseProductionTimeNoofEngineeringChangesTraditionalapproachFMEAapproach13EffectofFMEAonProcessandProcessFMEAForm14ProcessFMEAForm14JLExample15JLExample15ElementsofFMEAFailureMode Anywayinwhichaprocesscouldfailtomeetsomemeasurableexpectation.Effect

Assumingafailuredoesoccur,describetheeffects.Listseparatelyeachmaineffectonbothadownstreamoperationandtheenduser.Severity

Usingascaleprovided,ratetheseriousnessoftheeffect.10representsworstcase,1representsleastsevere.Causes

Thisisthelistofcausesand/orpotentialcausesofthefailuremode.Occurrence

Thisisaranking,onascaleprovided,ofthelikelihoodofthefailureoccurring.10representsnearcertainty;1represents6sigma.InthecaseofaSixSigmaproject,occurrenceisgenerallyderivedfromdefectdata.CurrentControls

Allmeansofdetectingthefailurebeforeproductreachestheend user,arelistedundercurrentcontrols.Detection Theeffectivenessofeachcurrentcontrolmethodisratedonaprovidedscalefrom1to10.A10impliesthecontrolwillnotdetectthepresenceofafailure;a1suggestsdetectionisnearlycertain.16ElementsofFMEAFailureModeProcessFailureModeThepotentialfailuremodeisthemannerinwhichtheprocesscouldfailtoperformitsintendedfunction.Thefailuremodeforaparticularoperationcouldbeacauseinasubsequent(downstream)operationoraneffectassociatedwithapotentialfailureinaprevious(upstream)operation.FAILUREMODEEFFECTPREVIOUSOPERATIONCAUSENEXTOPERATION17ProcessFailureModeThepotentProcessCauses

ProcessFMEAconsidersprocessvariabilitydueto:OPERATORSET-UPMACHINEMETHODENVIRONMENTMEASUREMENT18ProcessCausesProcessFMEACurrentControlsAssessmentoftheabilityofthecontroltodetectthefailurebeforetheitemleavesthemanufacturingareaandshipstothecustomer.CapabilityofallcontrolsintheprocesstopreventescapesSPCProcessCapabilityGageR&RSamplingTestingDOE19CurrentControlsAssessmentofTypesofMeasuresSEVERITYAsitappliestotheeffectsonthelocalsystem,nextlevel,andenduserOCCURRENCELikelihoodthataspecificcausewilloccurandresultinaspecificfailuremodeDETECTIONAbilityofthecurrent/proposedcontrolmechanismtodetectandidentifythefailuremodeTypically,threeitemsarescored:20TypesofMeasuresSEVERITYTypicRiskPriorityNumberRPN=OxSxD

Occurrencex Severityx DetectionOSD

xx=RPN21RiskPriorityNumberOSDxx=RPShortcomingsofRPN

A 8

4 3 96 B 4

8 3 96SAMERESULTFailureModeSeverityOccurrenceEffectivenessRPN22ShortcomingsofRPNSAMERESULTSeverity23Severity23Occurance24Occurance24Detection25Detection25Itisconductedonatimely

basisand

Itisappliedbyaproduct

teamandItsresultsaredocumentedFMEAisMostEffectiveWhen26ItisconductedonatimelybaWhatIsAGoodApplication?InvolvenewtechnologyHavechangedfrompreviousArechronicallyintroubleHaveahighdegreeofoperatorcontrolHaveahighdegreeofvariationChoosedesignsorprocesseswhich...InvolvenewtechnologyHavechangedfrompreviousArechronicallyintroubleHaveahighdegreeofoperatorcontrolHaveahighdegreeofvariationChoosedesignsorprocesseswhich...27WhatIsAGoodApplication?InvFMEAProcessManufacturingEngineerBuyerProcessOperatorProcessKnowledgePreviousExperiencePastProblemsChronicProblemsReliabilityEngineerProcessFunctions,PotentialFailureModesEffects,Causes,CurrentControlsActionPriorityActionstoEliminateorReduceFailureModeWarrantyClaims28FMEAProcessManufacturingBuyeBasicSteps1.DevelopaStrategy29BasicSteps1.DevelopaStrate1.DevelopaStrategy2.Reviewthedesign/process

EFFECTCAUSESBasicSteps301.DevelopaStrategyEFFBasicSteps1.DevelopaStrategy2.Reviewthedesign/process3.ListfunctionsDevelopaStrategyReviewthedesign/processListfunctions31BasicSteps1.DevelopaStrate1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.BrainstormpotentialfailuremodesBasicStepsBasicSteps:1.Developastrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes321.DevelopaStrategyBasicSte1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.OrganizepotentialfailuremodesBasicStepstopictopicAffinityDiagram331.DevelopaStrategyBasicSte1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.Organizepotentialfailuremodes6.AnalyzepotentialfailuremodesBasicSteps341.DevelopaStrategyBasicSte1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.Organizepotentialfailuremodes6.Analyzepotentialfailuremodes7.EstablishriskpriorityVITALFEWTRIVIALMANYBasicSteps351.DevelopaStrategyVITALTRIV1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.Organizepotentialfailuremodes6.Analyzepotentialfailuremodes7.Establishriskpriority8.TakeactiontoreduceriskBasicSteps361.DevelopaStrategyBasicSte1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.Organizepotentialfailuremodes6.Analyzepotentialfailuremodes7.Establishriskpriority8.Takeactiontoreducerisk9.CalculateresultingRPN’sBasicStepsO*S*D=RPN371.DevelopaStrategyBasicSte1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.Organizepotentialfailuremodes6.Analyzepotentialfailuremodes7.Establishriskpriority8.Takeactiontoreducerisk9.CalculateresultingRPN’s10.FollowupBasicSteps381.DevelopaStrategyBasicSteTestingtheRelationshipsIFTHENHOWDOIKNOW?CAUSEFAILUREMODEEFFECT39TestingtheRelationshipsIFTHEActionsThedesignorprocessmustbeimprovedbasedontheresultsoftheFMEAstudy.Awell-developedFMEAwillbeoflimitedvaluewithoutpositiveandeffectivecorrectiveactions.40ActionsThedesignorprocessmModuleObjectivesDescribeFMEAprinciplesandtechniques.Summarizetheconcepts,definitions,applicationoptionsandrelationshipswithothertools.PerformaFMEA41ModuleObjectivesDescribeFMEADescribeFMEAprinciplesandtechniques.Summarizetheconcepts,definitions,applicationoptionsandrelationshipswithothertools.PerformaFMEAModuleObjectives…...42DescribeFMEAprinciplesandtOrganizationalLearningandSystemsThinking组织学习和系统思维AManagementSystem43OrganizationalLearningandSyBuildingOrganizationalMemoryEyelashLearningCurveABILITYTODOJOBTIMEOLDEMPLOYEELEAVESWITHKNOWLEDGENEWEMPLOYEEBEGINSThereisnoorganizationalmemorytoallowpeopletostartwheretheirpredecessorsleftoffNothinginplacetocapturetheneworimprovedmethodsthatproduceresults*44BuildingOrganizationalMemoryRapidLearningCurveABILITYTODOJOBTIMENEWEMPLOYEECOMESONANDPICKSUPALMOSTWHEREPREVIOUSEMPLOYEELEFTOFFOrganizationcontinuestoadvanceitsknowledgebypreservingthelessonseachlearnsRapidlearning=lesswaste,lesscomplexity,highercustomervalue,lowercosts*45RapidLearningCurveABILITYTOHowDoWeCreateRapidLearning?Twokeyingredients:1.Havingbestknownmethodsdocumented2.TrainingpeopleonwhatthosemethodsareWhototrain?

NewemployeesManagersExperiencedemployees*SixSigma46HowDoWeCreateRapidLearninProsandConsofStandardMethodsAdvantages:优点Customerprogressismorevisibleandcanbetrackedovertime 顾客进步更可见而且可以随时间跟踪Captureandsharelessonslearned

吸取和分享教训Systemitselfdoesnotbecomeasourceofvariation

系统自身不会成为变异的来源Leadstoefficientpractices导致有效率的实践

*47ProsandConsofStandardMethProsandConsofStandardMethodsDisadvantages:缺点Stiflecreativityandleadtostagnation 抑制创造力导致停滞不前Interferewithcustomerfocus干涉客户的焦点Addbureaucracyandredtape助长官僚作风Makeworkinflexibleandboring 使工作欠缺灵活性，使人容易感到厌烦Onlydescribetheminimalacceptableoutput

只描述最小的可接受输出48ProsandConsofStandardMethFindingaBalance寻找平衡Thedifficultywefaceis....theargumentsforandagainststandardizationarebothtrue公说公有理，婆说婆有理Toachieveabalance,developstandardsjudiciously-whereitmattersthemostWheneffectivelymanaged,standardsprovidethefoundationforimprovement

49FindingaBalance寻找平衡ThediffEffectiveStandardization有效的标准Companiesthatusestandardizationeffectivelyoperateverydifferently:ThecompanyknowswhyitisdevelopingstandardsandhowtheycontributetoitsoverallpurposeManagementusesbest-knownmethodsthemselvesandstronglysupportsandchecksusageEmployeesunderstandhowdifferentfacetsoftheirworkaffecttheproductsandservices

Employeesknowwhichelements/functionsarecriticaltoproducinghigh-qualityoutput50EffectiveStandardization有效的标CreateStandardsJudiciously明智地创造标准LeveragePoint:Aplacewherealittlechangehasagreatimpact支点：小小的变化就能有巨大的影响的地方。三两拨千斤？“....everyjob,everyprocess,haswithinithigh-leveragepointsthatwemuststandardizeifwewanttoachieveconsistentlyhighperformance,andlow-leveragepointswherestandardizationissuperfluous,servingonlytorestrictflexibility.”51CreateStandardsJudiciously明KnowWhatIsandWhatIsNotImportant“Knowledgeaboutwhatisnotimportantisalmostasvaluableasknowledgeaboutwhatisimportant.Itfreesourattentiontobetterfocusonthefewthingsthatmakeadifference.”

“Thiskindofflexibilityshowsupinalljobs.”

“Asaruleofthumb,keepthedegreeofstandardizationaslowaspossiblebutdo

notneglectanyleveragepoints.”52KnowWhatIsandWhatIsNotILeveragePointThinking-HowDoYouTurntheShip?

KnowingtheleveragepointsiscriticalfordeterminingprioritiesandstrategiesforimprovementVitalFewTrivialManyParetoPrinciple80%oftheproblemsarecausedbyonlyabout20%ofthecontributingfactors*53LeveragePointThinking-How5454What’stheConnection?联系Companiesrunintotroublebecausetheychangetheirmethodsbeforetheyunderstandwhythemethodsarethereinthefirstplace.陷入麻烦的公司是因为他们在不了解现有方法存在的原因之前就盲目改变它。Theyeliminatesafetynetsintheirprocesseswithoutcontrollingthefactorsthatmadethemessential.55What’stheConnection?联系CompaResistthetemptationtochangeuntilwedetermine:

•Arethedocumentedstandardsthebest?

•Whatistheimpactontherestofthesystem?

•Arethemethodsactuallybeingfollowed?

What’stheConnection?56ResistthetemptationtochangEmployeeResponsibility员工的责任Beforeanyonecanbeheldresponsibleforthequalityoftheirownwork,theymust:1.Knowthejob

了解工作Isthejobclearlydocumented?Aregoalsandtargetsvisible?Hasadequatetrainingbeendone?Doworkersknowhowproductisused?2.Knowthestandard

了解标准Outputmustbemeasurablewithimmediatefeedbackonperformance.Don’tbevagueorrequireinterpretation(i.e.wordslikeflat,smooth,etc.)57EmployeeResponsibility员工的责任BEmployeeResponsibility(cont)3.Havetheabilitytoregulate

拥有调节的能力Whenthejobdoesnotmeetthestandard,aretherereactionprocedures?Arebestpracticesleveraged?Musthaveall3-inorder!(SeeAppendixAforChecklist)58EmployeeResponsibility(cont)CAP-Do-DeterminetheNeedforStandardization1.CheckMakesureweknowwhytheworkisbeingdone

SeeifthepurposeisclearlydocumentedCompareactualpracticewithdocumentedmethodsIfnodocumentedmethodsexist,comparedifferentpracticesamongpeopledoingtheworkComparehowtheeffectivenessoftheworkissupposedtobecheckedandhowitisactuallycheckedPLANDOACTCHECKToanswerthesequestions,usetheCAP-Do(variationofDeming’sPDCA-Plan-Do-Check-Act)59CAP-Do-DeterminetheNeedfoCAP-Do-DeterminetheNeedforStandardization

2.ActReconcileactualpracticesanddocumentationChangeonetomatchtheotherasappropriateIfnostandardmethodsareinplaceandnoonecandemonstrate(withdata)thatconsistencyamongoperatorsexists,simplyagreeonamethodthatallwilluse.Thiswillestablishaconsistentbaselineuponwhichimprovementscanbebuilt.PLANDOACTCHECK60CAP-Do-DeterminetheNeedfo3.PlanDeterminehowtodetectflawsandpotentialimprovementsinthestandardConductaPotentialProblemAnalysis(Kepner-Tregoe)todeterminecontingenciesandtriggersforcontingenciesDevelopaplanforupgradingthedocumentation,orformakingitmoreusefulDevelopaplanforencouragingtheuseofthedocumentedstandardCAP-Do-DeterminetheNeedforStandardization

PLANDOACTCHECK613.PlanCAP-Do-Determinethe4.DoTraintothenewdocumentedstandardUsethenewstandard5.CheckOnceagaincompareactualpracticestodocumentedstandardsInvestigateinconsistencies6.ActReconciletheactualpracticewiththedocumentationMakechangesbasedonthedata!!PLANDOACTCHECKCAP-Do-DeterminetheNeedforStandardization

624.DoPLANDOACTCHECKCAP-Do-De“TheIlliterateoftheYear2000...

2000年的文盲...willnotbetheindividualwhocannotreadandwrite,buttheonewhocannotlearn,unlearnandrelearn”不是不会读和写的人，而是不能学习、再学习和重新学习的人AlvinToffler*63“TheIlliterateoftheYear20FailureModeandEffectAnalysis

失效模式及其影响分析64FailureModeandEffectAnalysModuleObjectives课程目的DescribeFMEAprinciplesandtechniques.描述FMEA的法则及技巧。Summarizetheconcepts,definitions,applicationoptionsandrelationshipswithothertools.摘要概念、定义、应用的选择和其他工具的关联。PerformaFMEA执行一个FMEA。65ModuleObjectives课程目的DescribeFMEA:FailureModesandEffectsAnalysisFMEAisasystematicapproachusedtoexaminepotentialfailuresandpreventtheiroccurrence.Itenhancesourabilitytopredictproblemsandprovidesasystemofranking,orprioritization,sothemostlikelyfailuremodescanbeaddressed. FMEA是用来检查潜在失效和预防它再次发生的系统性方法.它增强了我们预测问题的能力,并提供了一个排序或区分优先次序的系统,因而使得最可能的失效模式得以确定.FMEAisgenerallyappliedduringtheinitialstagesofaprocessorproductdesign.Brainstormingisusedtodeterminepotentialfailuremodes,theircauses,theirseverity,andtheirlikelihoodofoccurring.InSixSigma,weapplyFMEAtoknowfailuremodes.Ourmaininterestsarethecauseandlikelihoodofoccurrence,forwhichwehaveactualdataanddonotneedtorelyonbrainstorming.FMEA通常应用在工艺及产品设计的初期，自由讨论决定潜在失效的模式、原因、严重度及发生的可能性。在6S中，我们应用FMEA去了解失效的模式。我们主要感兴趣的是原因及发生的可能性。FMEAisalsoavaluabletoolformanagingtasksduringdefect/failurereductionprojects.FMEA也是一个在失效缩小的管理任务的有价值的工具。FMEA66FMEA:FailureModesandEffectDefinitionofFMEA定义recognizeandevaluate

thepotentialfailuremodesandcausesassociatedwiththedesigningandmanufacturingofanewproductorachangetoanexistingproduct.

认识和评估新产品的设计和制造时或对现有产品做出改变时相关的潜在失效模式和原因identify

actionswhichcouldeliminateorreducethechanceofthepotentialfailureoccurring,

确定消除或减少潜在失效发生机会的行动document

theprocess.

使过程形成文件FMEAisa

systematic

designevaluationprocedurewhosepurposeisto:是系统的设计评估程序67DefinitionofFMEA定义recognizeFailuretoperformadefinedfunction 执行既定功能的失效Somethingoccurringthatyoudon‘texpect,orwant 发生了你不希望或不想要的事情Wrongapplication

应用错误AFailureModeis...失效模式是……68FailuretoperformadefinedfFMEAUsebyBlack/Brown/GreenBeltsToidentifypotentialfailuremodesandratetheseverityoftheireffectsToidentifycriticalcharacteristicsandsignificantcharacteristicsTorankpotentialdesignandprocessdeficienciesTohelpallofusfocusoneliminatingproductandprocessconcernsandpreventproblemsfromrecurringReducetheproductdevelopmenttimingandcost69FMEAUsebyBlack/Brown/GrBackgroundDevelopedinearly60’sbyNASAto“fail-proof”Apollomissions.Adoptedinearly70’sbyUSNavy.Bylate80’s,automotiveindustryhadimplementedFMEAandbeganrequiringsuppliersdothesame.Liabilitycostswerethemaindrivingforce.Usedsporadicallythroughoutindustryduring1980’s.AdoptedbyMSIin?

SixSigmaisthecatalyst.70BackgroundDevelopedinearly6NASAusedFMEAtoidentifySinglePointFailuresonApolloproject(SPF=noredundancy&lossofmission).Howmanydidtheyfind?420andwethoughtwehadproblems!71NASAusedFMEAtoidentifySinTypesofFMEA’sSYSTEMDESIGNPROCESSSystemFMEAisusedtoanalyzesystemsandsubsystemsintheearlyconceptanddesignstages.DesignFMEAisusedtoanalyzeproductsbeforetheyarereleasedtoproductionProcessFMEAisusedtoanalyzemanufacturing,assemblyandadministrativeprocesses72TypesofFMEA’sSYSTEMDESIGNPRWhenistheFMEAStarted?“Dothebestyoucanwithwhatyouhave”ASEARLYASPOSSIBLE!Guideline:73WhenistheFMEAStarted?“DotWhentoStart???Whennewsystems,productsandprocessesarebeingdesignedWhenexistingdesignsandprocessesarebeingchangedWhencarry-overdesignsorprocesseswillbeusedinnewapplicationsorenvironmentsAftercompletingaProblemSolvingStudy,topreventrecurrenceofaproblem74WhentoStart???WhennewsystBeginningandEnd75BeginningandEnd12EffectofFMEAonProcessandDesignchangesDesignStartDevelopmentProductionReleaseProductionTimeNoofEngineeringChangesTraditionalapproachFMEAapproach76EffectofFMEAonProcessandProcessFMEAForm77ProcessFMEAForm14JLExample78JLExample15ElementsofFMEAFailureMode Anywayinwhichaprocesscouldfailtomeetsomemeasurableexpectation.Effect

Assumingafailuredoesoccur,describetheeffects.Listseparatelyeachmaineffectonbothadownstreamoperationandtheenduser.Severity

Usingascaleprovided,ratetheseriousnessoftheeffect.10representsworstcase,1representsleastsevere.Causes

Thisisthelistofcausesand/orpotentialcausesofthefailuremode.Occurrence

Thisisaranking,onascaleprovided,ofthelikelihoodofthefailureoccurring.10representsnearcertainty;1represents6sigma.InthecaseofaSixSigmaproject,occurrenceisgenerallyderivedfromdefectdata.CurrentControls

Allmeansofdetectingthefailurebeforeproductreachestheend user,arelistedundercurrentcontrols.Detection Theeffectivenessofeachcurrentcontrolmethodisratedonaprovidedscalefrom1to10.A10impliesthecontrolwillnotdetectthepresenceofafailure;a1suggestsdetectionisnearlycertain.79ElementsofFMEAFailureModeProcessFailureModeThepotentialfailuremodeisthemannerinwhichtheprocesscouldfailtoperformitsintendedfunction.Thefailuremodeforaparticularoperationcouldbeacauseinasubsequent(downstream)operationoraneffectassociatedwithapotentialfailureinaprevious(upstream)operation.FAILUREMODEEFFECTPREVIOUSOPERATIONCAUSENEXTOPERATION80ProcessFailureModeThepotentProcessCauses

ProcessFMEAconsidersprocessvariabilitydueto:OPERATORSET-UPMACHINEMETHODENVIRONMENTMEASUREMENT81ProcessCausesProcessFMEACurrentControlsAssessmentoftheabilityofthecontroltodetectthefailurebeforetheitemleavesthemanufacturingareaandshipstothecustomer.CapabilityofallcontrolsintheprocesstopreventescapesSPCProcessCapabilityGageR&RSamplingTestingDOE82CurrentControlsAssessmentofTypesofMeasuresSEVERITYAsitappliestotheeffectsonthelocalsystem,nextlevel,andenduserOCCURRENCELikelihoodthataspecificcausewilloccurandresultinaspecificfailuremodeDETECTIONAbilityofthecurrent/proposedcontrolmechanismtodetectandidentifythefailuremodeTypically,threeitemsarescored:83TypesofMeasuresSEVERITYTypicRiskPriorityNumberRPN=OxSxD

Occurrencex Severityx DetectionOSD

xx=RPN84RiskPriorityNumberOSDxx=RPShortcomingsofRPN

A 8

4 3 96 B 4

8 3 96SAMERESULTFailureModeSeverityOccurrenceEffectivenessRPN85ShortcomingsofRPNSAMERESULTSeverity86Severity23Occurance87Occurance24Detection88Detection25Itisconductedonatimely

basisand

Itisappliedbyaproduct

teamandItsresultsaredocumentedFMEAisMostEffectiveWhen89ItisconductedonatimelybaWhatIsAGoodApplication?InvolvenewtechnologyHavechangedfrompreviousArechronicallyintroubleHaveahighdegreeofoperatorcontrolHaveahighdegreeofvariationChoosedesignsorprocesseswhich...InvolvenewtechnologyHavechangedfrompreviousArechronicallyintroubleHaveahighdegreeofoperatorcontrolHaveahighdegreeofvariationChoosedesignsorprocesseswhich...90WhatIsAGoodApplication?InvFMEAProcessManufacturingEngineerBuyerProcessOperatorProcessKnowledgePreviousExperiencePastProblemsChronicProblemsReliabilityEngineerProcessFunctions,PotentialFailureModesEffects,Causes,CurrentControlsActionPriorityActionstoEliminateorReduceFailureModeWarrantyClaims91FMEAProcessManufacturingBuyeBasicSteps1.DevelopaStrategy92BasicSteps1.DevelopaStrate1.DevelopaStrategy2.Reviewthedesign/process

EFFECTCAUSESBasicSteps931.DevelopaStrategyEFFBasicSteps1.DevelopaStrategy2.Reviewthedesign/process3.ListfunctionsDevelopaStrategyReviewthedesign/processListfunctions94BasicSteps1.DevelopaStrate1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.BrainstormpotentialfailuremodesBasicStepsBasicSteps:1.Developastrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes951.DevelopaStrategyBasicSte1.DevelopaStrategy2.Reviewthedesign/process3.Listfunctions4.Brainstormpotentialfailuremodes5.Organizepotentialfailure