FMEA失效模式分析PPT培训课件教材

12AnanalyticaltoolforidentifyingPotential

Failuresinaproductorprocesssothatcorrectiveactioncanbetakenbeforethefailurescanreachthecustomer.FMEA是一种识别产品或过程的潜在失效,以便在这些失效影响客户之前采取措施的分析工具3AnFMEAisaStructuredApproachto:FMEA是结构式的方法

Identifyingthewaysinwhichadesignorprocesscanfailtomeetthecriticalcustomerrequirements识别设计或过程可能以何种方式失效而不能满足客户重要需求

Estimatingtheriskofspecificcauseswithregardtothesefailures估计产生这些失效的特殊原因的风险

Evaluatingthecurrentcontrolsforpreventingthesefailures评估现有控制手段对这些失效的预防

Prioritizingtheactionsthatmustbetakentoimprovethedesignortheprocess给那些用以改进设计和过程的措施排序FMEA–History历史

Firstusedinthe1960’sduringtheApolloMoonMissions.

最早被用于上世纪六十年代的阿波罗登月计划.

In1974MIL-STD-1629wasdevelopedbytheNavyforusingFMEA’s. 1974年海军为FMEA的应用制定了MIL-STD-1629.Inthelate1970,adaptedbytheautoindustryinresponsetohigherliabilitycostsandhigherqualitydemandsbycustomers.

在二十世纪七十年代末,为满足客户更高的责任成本和质量需求而被用于自动化工业中.45FMEAisproactive,notreactive.Don'twaitforthecustomertocomplainifyoucanavoidit! FMEA是预防性

的，不是反应性的。应当尽量避免失效，而不是等着顾客提出申诉！

FMEAreducesthechancethatacustomerwillseeafailure FMEA通过以下措施减少顾客遇到失效的情况:Bydefiningfailureintermsofwhatthecustomerwantsandexpects.

针对顾客的要求和期望确定失效Byshowingwheremeasuresneedtobetakentopreventfailure.

指出为了防止失效，需要在哪方面采取措施

6TypesofFMEAs类型Design–usedtoanalyzeproductdesignsbeforetheyarereleasedtoproduction

设计-用于在产品投产前对设计的分析Process–usedtoanalyzemanufacturingprocesses

过程-用于分析制程System–usedtoanalyzesystemsintheearlyconceptanddesignstages

系统–用于分析早期的概念和设计时间的系统7Summary概要Identifiesknownandpotentialfailuremodes;

识别已知和潜在的失效模式Identifiesthecausesandeffectsofeachfailuremode;

识别每一种失效模式的原因和后果Prioritizesthefailuremodes(usingtheRPN);

利用风险序数（RPN）给失效模式排序Shouldinitiatecorrectiveactionwhereneeded.

必要时提出纠正措施89TimingofanFMEA

FMEA的时机FMEA’sshouldbeinitiatedwhenpreliminarydrawingsofthedesignorprocessareavailable

当初步的设计图纸和工艺被制定出来时应开始做FMEA

Updatedasidentifiedissuesareresolved

当被发现的问题解决后要更新FMEACanbeusedonexistingproductstoimprovequality

可用于现有的产品以提高质量10System系统Wiringharness

线束Electronicmodule

电控模块Assembly

总成SystemFMEAtreatssystemasa“functionalschematic”系统FMEA从“功能关系图”入手来考虑SFMEA11Ananalyticaltoolusedtoidentifysystem-levelfailuremodes,andidentifycorrectiveactionstobetaken.是一种分析工具用来识别系统失效模式12ItissimilartoaDesignFMEA,butfocusesonthecircuitschematicinsteadofphysicalfailureofcomponents.

同DFMEA相类似,系统FMEA侧重于回路设计而不是组件的物理失效。Takeelectricalsystemsasexamples.以电气系统为例。13Example: 举例：Failuremodeatelectricalsystemlevel

电气系统失效模式OpencircuitatcktA

回路A出现开路Cause:

原因：Terminalunseated

端子脱出Terminalunseated

becomesafailuremodeatthecomponentlevel.

端子脱出是电气组件的失效模式。RulesofDesignFMEA

设计FMEA规则

Toolfordesignengineersandprojectteamtoimprovethedesigninapreemptivemanner(beforefailureoccur)

是设计工程师和项目小组的工具用来提高设计的前瞻性(在问题发生前)

UsedtoestablishedCriticaltoQualityfeaturesthateffecttheperformanceoftheproduct

用与那些影响产品性能的重要质量特性Usedtoestablish

CriticaltoLifefeaturesthateffectthelifeoftheproduct

用于确定影响产品寿命的重要寿命特性UsedtoestablishCriticaltosafetyfeatures

用于确定重要安全特性1415PurposeofDesignFMEA

设计FMEA的用途Establishescriticalfeaturesthatmustbecontrolledinmanufacturingtosatisfycustomerrequirements

确定那些必须在生产中进行控制的特性以满足客户要求

Identifiesdeficienciesintheproductdesignandassociatedactionitems

找出产品设计中的不足和相应的措施Helpsevaluatetheriskofdesignchanges

帮助评价设计变更的风险16PurposeofDesignFMEA

设计FMEA的用途Identifiesprocessdevelopmentneeds

确定开发工艺流程的需求

Dynamicdocument–documentsdesignalternativesandassociatedrisks

动态的文件–记录可选择的设计方案和相应的风险Establishesbasesformanufacturingandqualitycontrolplan

建立制造和质量控制计划的基础17DesignFMEAInputsandOutputs设计FMEA的输入和输出

Productdrawings产品图纸

Productmodels产品模型

Productspecification产品规格

IdentifiedCriticaltoQualityfailures确定的重要质量特性

Actionstopreventthecausesoffailures防止失效原因的措施Actionstodetectfailuremodes发现失效模式的措施HistoryofactionsandResponsibilities措施和责任人的记录18Design

设计Components

组件Elements

设计要素DesignFMEAlooksatphysicalfailure

modesofcomponentsanddesignelements设计FMEA着眼于组件及设计要素的物理失效模式DFMEARulesofProcessFMEA

过程FMEA规则

Toolforprocessengineersandprojectteamtoimprovethemanufacturingprocessinapreemptivemanner

是工艺工程师和项目小组的工具,用来提高制造工艺的前瞻性

Usedtoprioritizeactionstoensureattentiontocriticalprocessesthateffectcustomers

用与区分先后顺序以确保那些影响客户的重要工艺Usedtodocumentprocessimprovements

用于工艺改进Dynamicdocumentforcontinuousimprovement

持续改进的动态文件1920PurposeofProcessFMEA

过程FMEA的用途Assistsintheanalysisofnewmanufacturingprocess

帮助分析新的制造工艺

Establishesthebasesformanufacturingprocessinstructionsandcontrolsheets

建立制造工艺文件和控制文件的基础Identifiesnewmanufacturingprocessneeds

确定新制造工艺的需求

Helpsevaluatetheriskofprocesschanges

帮助评估工艺更改的风险21Process

过程Manufacturing

制造Assembling

装配ProcessFMEAlooksatproductfailurescausedbytheprocessfailingtomeetrequirements过程FMEA着眼于因加工过程不符合要求所造成的产品失效PFMEAFMEATeam小组

Teamapproachisnecessary.

需要团队的方式ResponsibleforDesignFMEA–DesignEngineer

设计工程师负责设计FMEAResponsibleforProcessFMEA–ManufacturingEngineer

制造工程师负责过程FMEARecommendedrepresentatives:

推荐人选:Design/设计ManufacturingEngineers/制造工程师QualityEngineers/质量工程师Reliability/可靠性Materials/原材料Suppliers/供货商22DefinitionofTerms术语FailureMode–Thewayinwhichaspecificinputrequirementfailsandifnotdetected,correctedorremovedwillcauseanEffecttooccur.

失效模式

–一个特殊的输入要求失败的方式或者由于未被发觉,纠正或消除而带来的后果

Effect–Impactoncustomerrequirements

后果

–对客户要求的影响23DefinitionofTerms术语Cause–Source(s)ofprocessvariationthatcausestheFailureModetooccur.

原因

–造成失效模式发生的过程变差的起源

CurrentControl(proposedcontrols)

当前的控制(建议的控制)Designelementsthat

ensurefunction

确保功能的设计要素Mistakeproofing,automatedcontrols,setupinstructions,gauges

防错,自动化控制,机器设定指导书,量具Audits,checklists,inspections,PM,etc.. 稽核,检查表,检验,设备维护,等2425LinkingFailureModestoEffects失效模式和后果之间的联系FailureMode1FailureMode2Effect1FailureMode1Effect2Effect1FailureMode1FailureMode2Effect1NotethattherelationshipbetweentheFailureModeandEffectisnotalways1-to-1请注意失效模式和后果之间的关系不总是一对一Effect2RiskPriorityNumber风险序数

TheoutputofaFMEAisthe“RiskofPriorityNumber”---RPN

一个FMEA的输出是“风险序数”---RPN

TheRPNisacalculatednumberbasedoninformationprovidedregarding

RPN是根据下面的资料计算出来的

Thepotentialfailuremodes,

潜在失效模式Theeffects,and

后果Thecurrentorplannedabilitytodetectthefailurebeforeitreachesthecustomer

现有的和已计划的能力可以在影响客户前觉察失效26RiskPriorityNumber风险序数

Itiscalculatedastheproductofthreequantitativerating它是用三个级数计算出来的

RPN=Severity*Occurrence*Detection 风险序数=严重度*发生频度*探测度

TheRPNisnotsacred

RPN不是神圣的

ScalingforSeverity,Occurrence,andDetectionarelocallydeveloped严重度,发生频度,探测度的尺度由自己制定

Othercategoriesmaybeaddedtosuitneed

根据需要可以加上其他类型HighRiskPriorityNumbersaresignificanttothesuccessoftheproductdesign-actionsmustbetakentopreventfailures

高风险序数对产品设计的成功来讲很重要-需要采取措施来防止失效27DefinitionofRPNTermsRPN术语Severity(ofeffect)–Importancetocustomer,mayinvolvefunction,safety,reliability,orlifeofproduct(1=notsevere,10=verysevere)

严重度(后果的)

–对客户的重要程度,可包括功能,安全,可靠性,产品寿命等方面.(1=不严重,10=很严重)

Occurrence(ofcause)–FrequencywithwhichagivenCausemayoccur(1=notlikelytooccur,10=verylikelytooccur)

发生频度(原因的)

–一个特定的原因可能发生的频度(1=不可能发生,10=很可能发生)Detection(CapabilityofcurrentorplannedControls)–Abilitytodetectthecause(1=likelytobedetected,10=notlikelytobedetected)

探测度(现有的或已计划的控制能力)

–觉察原因的能力(1=有可能发觉,10=不可能发觉)2829RatingScales评分尺度Rating得分

DegreeofSeverity/严重程度

1Customerwillnotnoticetheadverseeffectoritisinsignificant/客户不会注意到或该不利后果不重要

2Customerwillprobablyexperienceslightannoyance/可能对客户有轻微的影响3Customerwillexperienceannoyanceduetotheslightdegradationofperformance/由于轻微的性能下降可能给客户带来麻烦

4Customerdissatisfactionduetoreducedperformance/由于性能下降使客户不满意

5Customerismadeuncomfortableortheirproductivityisreducedbythecontinueddegradationoftheeffect/客户不满意或受持续降级的影响使他们的生产力降低

6Warrantyrepairorsignificantmanufacturingorassemblycomplain/保修或者重大的制造或组装的投诉

7Highdegreeofcustomerdissatisfactionduetocomponentfailurewithoutcompletelossoffunction.Productivityimpactedbyhighscraporreworklevels/零件虽未完全失去功能但引起客户较大的不满;由于高报废,高返工率影响生产力

8Veryhighdegreeofcustomerdissatisfactionduetothelossoffunctionwithoutanegativeimpactonsafetyorgovernmentregulation/由于零件丧失功能而引起客户极大不满但尚未违反安全或国家规定

9Customerendangeredduetoadverseeffectonsafesystemperformancewithwarningbeforefailureorviolationofgovernmentalregulations/安全系统的不利影响使得客户处于危险当中但在失效前有警告或违反国家规定

10Customerendangeredduetoadverseeffectonsafesystemperformancewithoutwarningbeforefailureorviolationofgovernmentalregulations/安全系统的不利影响使得客户处于危险当中而且失效前没有警告或违反国家规定

30RatingScales评分尺度Rating得分

LikelihoodofOccurrence/发生的可能性1Likelihoodofoccurrenceisremote/发生的可能性极小2Lowfailureratewithsupportdocumentation/有书面证据证明发生的可能性很低3Lowfailureratewithout

supportdocumentation/发生的可能性很低但没有书面证据证明4Occasionalfailure/偶尔失效5RelativelyModeratefailureratewithsupportingdocumentation/有书面证据证明中等的失效可能性6Moderatefailureratewithout

supportingdocumentation/没有书面证据证明中等的失效可能性7Relativelyhighfailureratewithsupportingdocumentation/有书面证据证明高度的失效可能性8Relativelyhighfailureratewithout

supportingdocumentation/没有书面证据证明高度的失效可能性9Failureisalmostcertainbasedonwarrantydataorsignificanttesting/根据保修数据或重要试验几乎可以肯定失效会发生10AssureofFailurebasedonwarrantydataorsignificanttesting/根据保修数据或重要试验可以肯定失效会发生31RatingScales评分尺度Rating得分

AbilityofDetect/可探测度

1Surethatthepotentialfailurewillbefoundorpreventedbeforereachingthenextcustomer/确定潜在失效可以在到达下一个客户前被发现或预防2Almostcertainthatthepotentialfailurewillbefoundorpreventedbeforereachingthenextcustomer/几乎可以肯定潜在失效可以在到达下一个客户前被发现或预防3Lowlikelihoodthatthepotentialfailurewillreachthenextcustomer/潜在的失效到达下一个客户的可能性很低4Controlsmaydetectorpreventthepotentialfailurefromreachingthenextcustomer/控制手段可以防止潜在失效到达下一个客户5Moderatelikelihoodthatthepotentialfailurewillreachthenextcustomer/潜在的失效到达下一个客户的可能性中等6Controlsarelikelytodetectorpreventthepotentialfailurefromreachingthenextcustomer/控制手段不太可能防止潜在失效到达下一个客户7Poorlikelihoodthatthepotentialfailurewillbedetectedorpreventedbeforereachingthenextcustomer/在潜在失效到达下一个客户前发现或预防的可能性较低8Verypoorlikelihoodthatthepotentialfailurewillbedetectedorpreventedbeforereachingthenextcustomer/在潜在失效到达下一个客户前发现或预防的可能性非常低9Currentcontrolsprobablywillnotdetectthepotentialfailure/现有控制手段可能探测不到潜在失效10Absolutecertainlythatthecurrentcontrolswillnotdetectthepotentialfailure/完全肯定现有的控制手段无法探测潜在失效32ExamplesofOccurrencescale发生率评分的例子ScaleValue分值OccurrencesperWeek周Day日Shift班Hour小时107001003349500712438350501727200291016100145157511445072325412711133ExamplesofDetectionscale探测度评分的例子ScaleValue/分值Percentofpotentialfailuresprevented预防潜在失效的比率190%280%370%460%550%640%730%820%910%100%34ProcessStep/InputPotentialFailureModePotentialFailureEffectsSEVPotentialCausesOCCCurrentControlsDETRPNActionsRecommended0000000000000000Whatistheinput?输入是甚么?Whatcangowrongwiththeinput?输入会出甚么错?WhatistheEffectontheoutput?输出的后果是甚么?Whatarethecauses?原因是甚么?Howwell?程度如何?Howcanthisbefound?怎样才可以发现?Howoften?频繁程度Whatcanbedone?可以做甚么?Howwell?程度如何?35FMEA–FAILUREMODEEFFECTSANALYSISProduct:ProcessStep/InputPotentialFailureModePotentialFailureEffectsSEVPotentialCausesOCCCurrentControlsDETRPNActionsRecommendedResponsibilityWhatisthesteporinputunderinvestigation?Inwhatwaydoesthekeyinputgowrong?Whatistheimpactonthekeyoutputvariable(customerrequirementorinternalrequirement)Howsevereistheimpactonthecustomer?Whatcausesthekeyoutputtogowrong?Howoftendoescauseoffailuremodehappen?Whataretheexistingcontrolsandprocedures(inspectionandtesting)thatpreventeitherthecauseorthefailuremode?IncludeshopoperatingprocedurenumberHowwellcanthefailuremodeofcausebedetected?RPN=SEV*OCC*DETWhataretheactionsforreducingtheoccurrenceofthecauseorimprovingdetection?ShouldhaveactionsonallhighRPNnumbers.Whoisresponsibleforimplementingtherecommendedactions?000036FMEAModel模式Prevention/预防Prevention/预防Prevention/预防Cause/原因Effect/后果FailureMode/失效模式Controls/控制Materialorprocessinput/原料或过程输入ProcessStep/工序Externalcustomerordownstreamprocessstep/外部客户或下一工序GeneralStepsintheDFMEA/一般步骤

SelectdesignFMEAteam

组建设计FMEA小组Listcustomerrequirements

列出客户的要求

Foreachcustomerrequirementlistthekeydesignelementsthatsatisfythecustomerrequirements

针对客户的每一个要求列出满足该要求的关键设计要素Foreachkeydesignelementlistwaysthatthedesignelementcouldvary,PotentialFailureModes

列出每一个关键设计要素的变化,潜在的失效模式ListEffectsofeachFailuremodeonthecustomerrequirement

列出每个失效模式的对客户要求的影响ListCausesforeachfailureMode

列出失效模式的原因37GeneralStepsintheDFMEA/一般步骤

Listcurrentcontrolsforeachcause

列出每个原因的现有控制手段

AssignSeverity,Occurrence,andDetectionratingstoeachcause

给每个原因的严重度,频度,可探测度评分CalculateRPNs

计算风险序数RecommendactionstoreducehighRPNs

提出降低风险序数的措施Takeappropriateaction

采取适当的措施

RecalculateRPNs

重新计算风险序数3839Aschematicrepresentation,with

一种图示法,其中

Components(orfeatures)shownasblocks,

用方块表示各组件(或特性)Interactionsbetweencomponentsshownaslines,

用直线表示各组件之间的关系Attheappropriatelevelofdetail

详细到恰当的程度

DevelopaFunctionalBlockDiagramofTheProduct

绘制产品功能结构图40Component组件Component组件Component组件Component组件Component组件Component组件BlockDiagram结构图Examples例如41Don'tforgetauxiliaryfunctionsaswellaprimaryfunctions

主要功能和辅助功能都要考虑Often,componentsworktogethertoperformafunction

经常是几个零件共同实现一个功能Hint:UsetheBlockDiagram!

提示:利用结构图ListTheFunction(s)ofEachComponent

列出每个要素的功能42Adefect,flaw,orotherunsatisfactoryconditionintheproductthatiscausedbyadesignweakness

由于设计缺陷造成的产品缺陷,瑕疵或其它令人不满意的情况TypicalFailureModes:

典型的失效模式

-Breaks -Cracks

破碎

裂纹

-Corrodes -Sticks

腐蚀

粘结

-Deforms/melts

变形/熔化43Startwiththeprevioustwosteps:

从前両个步骤入手:

Functions

功能Qualityrequirements

质量要求44Inyourowndescriptivewords,writedownthefollowingscenarios，用自己的语言描述下列假设：

Failure=Nofunction，失效=无功能Failure=Notenoughfunction，失效

=功能不足Failure=Toomuchfunction，失效

=功能过强Similarly,同样：Failure=Noqualityrequirement

失效=未达到质量要求45Aneffectcanbe，后果可能是：Completelossoffunction，功能完全丧失Degradationofperformanceorquality

性能或质量下降Manyfailuremodeshavemorethanoneeffect!

许多失效模式不止有一个后果！Effectsoffailureoftenshowupasachainofevents,fromimmediateeffecttotheultimateeffectonthecustomer

失效模式的后果经常表现为对客户的一连串的影响,包括直接的后果和最终的后果46DeterminePotentialCause(s)ofEachFailureMode

确定每种失效模式的潜在原因Acauseoffailureisadesignweaknessthatleadstothefailuremode

造成失效的原因是由于设计缺陷引起Inherentinthewaytheproductwasdesigned

是产品设计所固有的Relativetotheusageoftheproduct

与产品的使用方法有关Manyfailuremodeshavemultiplecauses!

许多失效模式有多个起因！47Ifthedesignas-isweretogointoproduction.如果依据现有设计进行生产的话Usehistoricaldata，利用历史数据Takeimprovementsintoaccount，参考已有的改进Considerthelifespanoftheproduct，考虑产品的寿命Usereliabilitymodelsandcomparisonwithsimilarproducts，利用可靠性模型并与类似产品比较AssessTheLikelihoodofOccurrenceofEachCause

评估每种原因发生的可能性48Therearethreetypesofdesigncontrols:

设计控制有三种类型：(1)Thosethatpreventthecauseoffailure;

预防产生失效的原因；(2)Thosethatdetectthecause(s)offailure;

觉察产生失效的原因；(3)Thosethatdetectthefailuremode(s)检测失效模式49DetectionRating(D):探测度评分 9-10 Remotechanceofdetectingfailure

察明失效的可能性极小 7-8 Verylowchance，可能性很小 5-6 Lowtomoderatechance，可能性不大 2-4 Goodchance，可能性较大1 Willalmostcertainlydetectfailure (Ifitpassesthis,itwillnotfail)

失效几乎都可以被査到(如果通过这样的 检查就不会有失效)50Toreduceseverity--designchangetocontroltheeffect

降低严重度–通过设计更改来控制后果Toreduceoccurrence--designchangetocontrolthecause

减少发生频度--通过设计更改来控制原因Toimprovedetection--improvedtestingorsimulationmethods

增强探测度–改进测试和模拟方法Special

AttentionifSeverity=9or10

当严重度为9或10时要特别注意GeneralStepsinthePFMEA/一般步骤

SelectprocessFMEAteam

组建过程FMEA小组

DevelopaProcessMapandidentifyallprocesssteps

做一个流程图确定过程的所有步骤ListalltheKeyProcessOutputstosatisfyinternalandexternalcustomerrequirement

列出所有的满足内部和外部客户要求的关键过程输出Foreachprocessstep,listKeyProcessInputVariables

列出每一步的关键过程输入变量FortheProcessDefineC&EmatrixrelatingKeyOutputstoKeyProcessInputVariable

用因果图分析关键过程输入和关键输出的联系

RanktheKPIVsaccordingtoimportance

根据重要程度给关键过程输入变量分级

StarttheprocessFMEA

开始做过程FMEA51GeneralStepsinthePFMEA/一般步骤

Foreachprocessinput,listwaysthatitcanvary(failureModes)andidentifyassociatedeffects

对每一个过程的输入,列出其可能的变化和相应的后果

ListallCausesforeachFailureMode

列出失效模式的所有原因ListthecurrentControlsforeachcause

列出每个原因的现有控制手段AssignSeverity,Occurrence,andDetectionratingstoeachcause

给每个原因的严重度,频度,可探测度评分CalculatetheRPNforeachpotentialFailureModescenario

计算每个潜在失效模式的风险序数

DeterminerecommendedactionstoreduceHighRPNs

提出降低风险序数的措施

Takeappropriateactions

采取适当的措施RecalculateRPNs

重新计算风险序数5253UsetheProcessFlowDiagramformat

适用流程图的格式Identifiesfabricate,move,storeandinspectoperations

识别四种作业类型,制造,移动,储存,检验IdentifiesKeyCharacteristics

识别关键特性Afunctioniswhattheoperationdoes

功能系指该操作所起的作用

Statethefunctionas/说明功能为：Verb+Object+Qualifier

动词+宾语+修饰词

Moldpart/成型零件

Crimpterminalontocable/电线上压接端子

Formbendinpart/零件弯曲成形54Acustomerwantordesire

顾客的希望或要求

Couldseriouslyaffectcustomerperception

有可能严重影响顾客的看法

Couldleadtoacustomercomplaint 有可能导致顾客投诉

Adefect,flaw,orotherunsatisfactoryconditionintheproduct

thatoccurswhentheprocessfailstomeettheprocessrequirements

由于过程未达到要求而导致的产品缺陷、瑕疵等不良状态

Failuremodesshouldbewrittenintermsoftheconditionoftheproduct

失效模式体现在产品上

55

TypicalFailureModes/几种典型失效模式

Diameteroutofspec./直径超差Missingseal/漏装密封垫Cutstrands/切破线皮Miss-orientedpart/部件方向错Insufficientsolder/焊剂不足Toomuchsolder/焊剂过量NFO,Flash/未充满,飞边Theramificationsoffailure/后果是失效模式的衍生事件

Theeffectcanbeon/可能影响Theultimatecustomer/最终用户Orintermediatecustomer(OEM,etc.)/中间用户Agovernmentregulation/政府法规Thenextprocessstep/下工序56

Customercomplaintsareausefulsourceofinformation顾客抱怨是非常有用的信息来源

Aneffectcanbe/后果可能是

Completelossoffunction/功能完全丧失Degradationofperformanceorquality/质量或性能下降Damageofprocessequipment/设备受损

Injurytoanoperator/员工受伤Shut-downofanassemblyline/停线Effectsoffailureoftenshowupasachainofevents,fromimmediateeffecttotheultimateeffectonthecustomer/失效的后果

通常表现为从对顾客的直接影响到最终影响等一系列连锁反应

ItisrecommendedthatthesechainsbedevelopedforeachfailuremodeandrecordedontheFMEAform/建议针对每一种失效模式找出这些连锁反应，并记录在FMEA表上

57Acauseoffailureishowthefailurecanoccurintheprocess失效原因就是过程为何会失效

Shouldbewrittenintermsofsomethingintheprocessthatcanbecorrectedandcontrolled应表述为可纠正或可控制的因素

Considerhumanerror,wear-outoftools,ambientconditions,andinteractionsoffactors如人的过失，工装磨损、环境条件以及因素间的相互作用

58Effectsontheprocess/对过程的影响9-10

Mayendangermachineoroperator/ 可能导致设备或人员受损

6-8 Scrap/报废4-5

Sortandrework/筛选和返工2-3

Reworkon-line/在线返工1

Noeffect/无影响ConsiderAlsotheEffectsontheCustomer还要考虑对顾客的影响59

Usehistoricaldata(asabaseline)/利用历史数据

Takeimprovementsintoaccount

考虑改进9-10 Failurealmostinevitable/失效几乎不可避免

7-8

Similarprocessesthathaveoftenfailedinthepast

以前类似过程常常失效

4-6

Similarprocessesthathaveoccasionalfailures

类似过程偶尔失效

1-3

Similarprocessesthathaveexperiencedisolated failures/类似过程仅有过个别失效

Cause-and-EffectChain因果链60ToolIsWorn夹具磨损ToolNotReplaced夹具未更换LackofMaintenanceProcedure/没有保养程序ClampCracksatBend夹子在弯曲处裂纹BundleFallsOut线束散开RattlingNoise卡嗒声噪音CA