DFMEA失效模式与后果

DFMEA------失效模式与后果分析

(DesignFailureMode&EffectAnalysis)Marian(Shenzhen)Co.,Ltd编制：曹喜元FormationBy：JackCao

日期：

Date：1-Feb-2013主要内容

Maincontent1.DFMEA介绍4.DFMEA关键参数DFMEAPresentationDFMEAKeyParameter2.DFMEA职责5.DFMEA表单填写说明DFMEAResponsibilityDFMEAFormFillingExplanation3.DFMEA制作流程6.DFMEA案例DFMEAMakeProcessDFMEAExample一、DFMEA的介绍

DFMEAPresentationDFMEA是FMEA中的一种，FMEA分为：DFMEA和PFMEADFMEAisintheFMEAonetype,FMEAContain:DFMEA&PFMEADFMEA是由负责设计的工程师或小组，在产品设计阶段尽可能的范围内预估产品在设计上可能发生的缺点.DFMEAisEngineerorgrouptoresponsiblescheme,Asfaraspossiblewithinthescopeoftheestimatedproductdesignonthepossiblefaultsintheproductdesignstage.PFMEA是由负责制造装配的工程师或小组，预估产品在生产过程阶段或之前可能会发生的缺点.PFMEAisPEorgrouptoresponsiblescheme,Asfaraspossibletheestimatedproductpossiblefaultsintheproductiveprocessorbefore.本章节重点讲述DFMEAThischapterfocuseson

DFMEA.DFMEA的形成

DFMEAFormationDFMEA是由负责设计的工程师或小组，在尽可能的范围内预估产品在设计上可能发生的缺点，衡量该项缺点或可能造成的影响，并拟定为防止或检测该缺点应改善的设计控制，并推动其标准化作业，且必须配合设计发展之程序反复执行.DFMEAisEngineerorgrouptoresponsiblescheme,Asfaraspossiblewithinthescopeoftheestimatedproductdesignonthepossiblefaultsintheproductdesignstage,Measurethefaultsorcancauseinfluence,andplantopreventortestingthedefectshouldbeimproveddesigncontrol,andpromotethestandardizedoperation,andmustfitinwiththedevelopmentofdesignprogramandimplementation.最终成品及其所有相关的系统、子系统都应纳入评估.DFMEA是设计小组，即公司工程，运用设计，工程经验或分析方法等而形成的.Thefinalandallrelatedsystem,subsystemshouldbeincludedinassessment.DFMEAisthedesignteam,namelythecompanyproject,theuseofdesign,engineeringexperienceoranalysismethodsandform.DFMEA必备条件

DFMEAEssentialCondition

确认已知及潜在的失效模式；Confirmtheknownandthepotentialfailuremode.

确认每一个失效模式的效应和原因；

Confirmeachfailuremodeeffectandreasons.

风险优先评估（严重性、发生频率、难检度）；Riskpriorityevaluation(severity,occurrencefrequency

anddifficulttocheckdegree)

提供问题的数据及改善行动；Provideproblemofdataandimprovementaction.

DFMEA的动态链

DFMEATrendsCatenationDFMEA是个循环过程，在设计方案最终形成之时或之前开始.DFMEAisacyclicprocess,thedesignschemeoffinalformorbeforethestart.在产品开发各阶段中，当设计有变化或得到其他信息时，应及时，不断地修改，最终在产品加工图样完成之前全部结束。Ineverystageofproductdevelopment,whenthedesignchangeorgetotherinformation,shouldbeprompt,constantlymodified,finally,inproductprocessingpatternuntilallover.二、DFEMA职责

DFMEAResponsibility

工程经理：DFMEA总体负责人，负责组建DFMEA团体，提出DFMEA实施计划，并组织召开DFMEA会议，分配团队人员任务

组织DFMEA评审，DFMEA审核.Projectmanager:generalmanager,responsibleforDFMEA,this

paperputsforwardaDFMEAgroupDFMEAimplementationplan,

andorganizeaDFMEAmeeting,distributionteampersonneltask

OrganizationDFMEAreview,DFMEAaudit.

工程师：负责主导DFMEA文件编写、修改和升级.Engineer:responsibleforleadingDFMEAdocumentpreparation,

modificationandupgrade.二、DFEMA职责

DFMEAResponsibility

工程助理：负责客户投诉问题，研发、试产、量产中问题的收集，及

时反馈到DFMEA团体负责人处，并参与O,S,D参数评估，提供量

产CPK数据.Projectassistant:responsibleforcustomercomplaintproblem,research

andtrialproduction,thequantityofcollection,andrenderWhenthe

feedbacktoDFMEAgroupplace,andparticipateinO,S,Dparameter

evaluation,SupplyvolumeproductionCPKdata.

试样工程师：负责研发产品测试过程中所出现问题点的收集并及时

反馈到DFMEA负责人处，参与O,S,D参数评估.Sampleengineer:responsibleforresearchanddevelopmentinthe

processofproducttestingproblemspointcollectionandtimelyfeedback

totheDFMEAchiefplace,participateinO,S,Dparameterevaluation.二、DFEMA职责

DFMEAResponsibilityCQE：负责客户需求信息归纳整理，DFMEA建议措施监督实施、追

踪，实施效果反馈，根据DFMEA和客户需求等信息制定控制计划，

并参与

O,S,D参数评估.CQE:Beresponsibleforthecustomerdemandinformationsummary,

DFMEAsuggestedmeasuressupervisionandimplementation,

trackingandeffectfeedback,accordingtotheDFMEAandrequirementsforinformationsuchascontrolplan,andparticipatein

O,S,Dparameterevaluation.三、DFMEA制作流程

DFMEAMakeprocess

注：团队制定目标，使团队清楚新产品或以改善为

目标，并需要了解客户需求。

Note:Theteamsetgoals,maketheteamclear

newproductsortoimproveasthegoal,and

needtounderstandcustomerneeds.

使用方法；Methodofapplication.

客户要求的设计/工程SPEC；Customer

requestedproject&EngineeringSPEC.

产品信赖；ProductTrust.

制程、生产、装配要求；Process,Production

AssembleofRequirement.

品质目标.QualityDestination.组成DFMEA团队ConstituteDFMEATeam确定目标ConfirmDestination三、DFMEA制作流程DFMEAMakeprocess产品设计及类类似产品设计计的问题及原原因；Productdesignandsimilarproductdesignproblemsandreasons制造工艺及类类似产品制程程中常及的不不良原因；Manufacturingprocessandsimilarproductsinprocessandbadreason.类似产品的制制程能力及原原因；Similarproductsofprocesscapabilityandthereason.类似产品的客客诉及原因；；Similarproductsofcustomercomplaintandthereason.类似产品的依依赖性失效及及原因；Similarproductsthedependenceofthefailureandthereason.类似产品的管管理性问题；；Similarproductsofmanagerialproblems.资料收集DataCollection三、DFMEA制作流程DFMEAMakeprocess使用维修；UseMaintain.环境.Environment.表格格格式TableFormat.分层层层次DelaminationAdministrativelevels.失效定定义FailureDefinition.成果整整合AchievementIntegration.时机Opportunity.资料收收集DataCollection制订执执行方方案FormulateimplementPlan三、DFMEA制作流流程DFMEAMakeprocess分析制制程特特性AnalysisProcessCharacter定义制制造流流程DefinitionproductionProcess分析产产品特特性AnalysisProductCharacter分析析失失效效原原因因AnalysisFailureCause分析析现现行行控控制制方方法法AnalysisControlMethod分析析失失效效效效应应AnalysisFailureEffect分析析发发生生率率AnalysisOccurrenceRate分析析难难检检度度AnalysisDetection分析析严严重重度度AnalysisSeverity计算算风风险险优优先先数数CalculatedRiskPriorityNumber分析析制制程程特特性性AnalysisProcessCharacter三、、DFMEA制作作流流程程DFMEAMakeprocess决定定优优先先改改善善的的失失效效模模式式DecideAmeliorativeFailureMode建议议改改善善措措施施RecommendationImprovementMeasures改善善实实施施ImprovementImplement结果果确确认认有有效效ResultNotarizeEffective四、、DFMEA关键键参参数数DFMEAKeyParameter严重重度度、、发发生生率率、、难难检检度度、、风风险险优优生生数数Severity,Occurrence,Detection,RPN严重重度度Severity-----------------------------S发生生率率Occurrence------------------------O难检检度度Detection---------------------------D风险险优优生生数数RiskPriorityNumber-------RPNRPN=S*O*D四、、DFMEA关键键参参数数DFMEAKeyParameter严重重度度Severity衡量失失效效的的影影响响程程度度.Assessmentfailureincidence失效效影影响响产产品品或或制制程程，，某某一一失失效效会会对对产产品品外外观观、、结结构构、、功功能能、、性能能稳稳定定性性、、可可靠靠性性的的影影响响；；或或对对下下一一个个制制程程，，使使用用者者和和设设备的的影影响响；；或或对对最最终终客客户户，，政政府府法法规规、、安安全全、、环环保保等等的的违违及及.Failureaffectproductorprocess,afailuretoproductappearance,structure,function,performancestabilityandreliabilityoftheinfluence;Ortothenextprocess,theuserandtheinfluenceoftheequipment;Ortoendcustomers,governmentregulations,safety,andenvironmentalprotection,andadefault.四、DFMEA关键参数数DFMEAKeyParameter严重度Severity严重度的的划分标标准---------------------------------------主观判定定SeverityClassificationStandard-------------------SubjectivityDecide其大小由由失效模模式的影影响程度度而定，，以1至10表示等级级.It’ssizeofthefailuremodeoftheinfluencedegreetodecide,be1to10showlevel.1级最轻微微，10级最严重重.1Levelbestslight,10Levelbestgrave.1级-------------------------------几乎不会会有什么么影响.1Level--------------------------Almosthasnoinfluence.10级-----------------------------违反安全全和法规规.10Level-------------------------Violationofsafetyandregulations.四、DFMEA关键参数数DFMEAKeyParameter严重度分分类SeverityClassify耐火性、、自然性性、UL、RHoS&HFFireResistance,Naturalness,UL,RHoS&HF一、危危险特性性Catastrophic工业标准准(无法满足足而不能能销售））IndustryStandardIncapableConnotMarket.客户要求求CustomerRequest内部工程程需要由由Critical测量项目目InternalENGneedforcriticalmeasureproject四、DFMEA关键参数数DFMEAKeyParameter严重度分分类SeverityClassify客户及供供应商共共同制定定特性；；CustomerandSuppliertogetherformulatefeatures.二、重大大特性Significant或客户指指定特性性，如导导电或绝绝缘；(满足而而不能能销售售给指指定客客户)Orcustomerappointfeatures,ForinstanceEC&Insulation.ContentConnotMarket设计工工程指指定的的特性性；DesignationCustomerDEappointfeatures.行业标标准.Industrialstandard.四、DFMEA关键参参数DFMEAKeyParameter严重度度分类类SeverityClassify可靠性性测试试，如如拉拔拔力测测试；；.ReliabilityTesting,Forexampledrawingforcetest.三、主主要特特性Major产品制制程不不良率率及分分析Productprocessrejectratioandanalysis.四、DFMEA关键参参数DFMEAKeyParameter严重度度等级级标准准SeverityRankStandard等级/评分Rank划分标准DivideStandard1几乎无影响Almostnoinfluence2产品在客户使用组装过程中，组装性差，客户一般难已发现，关注的问题.Productsinthecustomerstouseassemblyprocess,assemblysexdifference,thecustomergeneraldifficulthasfound,payattentiontotheproblem.3产品之中主要应用的功能稍有瑕疵，如绝缘等，非专业人员无法识别，EMCII级要求.Theproductismainlyusedinthefunctionoftheslightlydefects,suchasinsulation,laypeoplecan'tidentify,EMClevelIIrequirements.4在高于产品承诺的环境中使用失效，但此环境低于公司内部控制标准或者已达到行业协会标准要求，EMCI级要求.不符合标准化的定义.Intheaboveproductpromisedenvironmentwithfailure,buttheenvironmentislowerthantheinternalcontrolstandardsorhasreachedindustryassociationstandardrequirements,EMCIlevelrequirement.Donotconformtothestandarddefinition.四、DFMEA关键参参数DFMEAKeyParameter严重度度等级级标准准SeverityRankStandard等级/评分Rank划分标准DivideStandard5存在的问题使产品长期运行的可靠性能降低，如产品粘力、导电产品的导电性能等，产品结构复杂，甚至需要培训才能完成或当前的技术无法解决的功能性问题.Problemsmaketheproductlong-termoperationofthelowerreliability,suchasproductviscousforce,conductiveproductsofconductiveperformanceandsoon,theproductstructureiscomplex,evenneedtrainingtocompleteorcurrenttechnologycannotsolvetheproblemoffunctional.6产品维护复杂，装配、生产非常困难；设计的产品公司工艺无法完成；客户独特配件的兼容性问题；不能95以%以上机率复现的问题；计算机监测功能失效或误差大.Productmaintenance,assembly,productionisverydifficult;Designproductscompanyprocesswasunabletocomplete;Customeruniqueaccessoriescompatibilityproblem;Can't95to%aboveprobabilityreproduction;Computermonitoringfunctionfailureorbigerror.7客户关注的重点功能性问题或者是产品主推场所应用的兼容性问题；产品量化参数不达标.Customerfocusofconcernfunctionalproblemsoristheproductofthemainplacetheapplicationcompatibilityproblem;Productquantitativeparametersnotstandard.四、DFMEA关键参参数DFMEAKeyParameter严重度度等级级标准准SeverityRankStandard等级/评分Rank划分标准DivideStandard8基本功能失效，失效影响计算机数据处理功能.Thebasicfunctionfailureandinfluencethecomputerdataprocessingfunction.9影响产品安全运行或者包含不符合法律、法规；产品执行标准影响人身安全；产品失效时有警告.Influencethesafeoperationoftheproductorcontaindoesnotcomplywiththelaws,rulesandregulations.Productstandardsaffectpersonalsafety;Productfailureiswarning.10影响产品安全运行或者包含不符合法律、法规；产品执行标准影响人身安全；产品失效时无警告.Influencethesafeoperationoftheproductorcontaindoesnotcomplywiththelaws,rulesandregulations.Productstandardsaffectpersonalsafety;Productfailureisn’twarning.四、DFMEA关键参参数DFMEAKeyParameter发生率率Occurrence某一原原因而而导致致失效效发生生的几几率.Areasontotheoddsoffailure.划分标标准：：依据据不良良品出出现的的机率率来定定，以以1至10表示等等级.Thedivisionstandard:accordingtotheprobabilityofbadproductappearedtodecide,be1to10showlevel.1级最轻轻微，，10级最严严重.1Levelbestslight,10Levelbestgrave.1级-------------------------------几乎不不会发发生.1Level--------------------------Almostwon'thappen.10级-----------------------------肯定会会发生生.10Level-------------------------Willhappen四、DFMEA关键参参数DFMEAKeyParameter发生率率Occurrence划分标标准--------------------------------------CPK、主观观判定定、统统计资资料DivideStandard--------------CPK,Subjectivejudge,statisticalinformation划分标准DivideStandard等级/评分Rank描述Describe发生率OccurrenceCPK1(Remote)几乎不可能发生Almostwon'thappen.1/1500K≥1.672(VeryLow)有轻度发生的可能Withmildpossible1/150K≥1.503(Low)有可能发生possible1/15K≥1.334(Moderate)偶尔发生，但不占有大的比例Occasionallyoccur,butdon'thavegreatproportion1/2K≥1.175(Moderate)1/400PCS≥1.006(Moderate)1/80PCS≥0.83四、DFMEA关键参数DFMEAKeyParameter发生率Occurrence划分标准--------------------------------------CPK、主观判定定、统计资资料DivideStandard--------------CPK,Subjectivejudge,statisticalinformation划分标准DivideStandard等级/评分Rank描述Describe发生率OccurrenceCPK7(High)经常发生Oftenoccur1/20PCS≥0.678(High)1/8PCS≥0.519(Veryhigh)几乎不可避勉Almostdonotavoidlayer1/3PCS≥0.3310(Veryhigh)1/2PCS<0.33四、DFMEA关键参数DFMEAKeyParameter难检度Detection在现行的控控制措施下下，侦测失失效发生的的能力.Inthecurrentcontrolmeasures,theabilitytodetectfailurehappened.划分标准：：依据失效效模式检验验的难易程程度来定，，以1至10表示等级.Thedivisionstandard:Accordingtothefailuremodeofthetestdifficultytoset,be1to10showlevel.1级最容易，，10级为几乎不不可能发现现.1Levelbesteasy,10LevelforAlmostimpossibilityfind.1级-----------------------用有效的手手段完全可可以检测出出来1Level-------------------Witheffectivemeanscompletelycanbedetected.10级----------------------无任何手段段可以检测测出来.10Level------------------Nomeanscanbedetected.四、DFMEA关键参数DFMEAKeyParameter难检度Detection划分标准--------------------------------------主观判定、、统计资料料DivideStandard--------------Subjectivejudge,statisticalinformation划分标准DivideStandard等级/评分Rank描述Describe可侦度Detection1~2几乎可以肯定地检测出来Almostcertainlydetected≥99.99%3~5有良好的手段可以检测出来Havegoodmeanscanbedetected≥99.80%6~8可能能检测出来Mightbeabletotestout≥98.00%9有可能检测不出Maycannotbedetected≥90.00%10很有可能检测不出来Verylikelytestdoesnotcomeout≤90.00%四、DFMEA关键参数DFMEAKeyParameter风险系数RiskPriorityNumberRPN=S*O*D风险系数RPN排出次序后后，RPN越大越优先先解决.RPN在100以上必须解解决；50<RPN<100应尽可能解解决，不能能解决必须须加严控制制；RPN<50可不加控制.当严重度(S)很高或发生生率(O)很高时，不不管RPN大小如何，，都必制定相应改改善或控制制措施，并并指定责任任人和改善善完成日期期.RiskcoefficientRPNdischargeorder,thebiggertheRPNpriority.RPNinmorethan100mustbesolved;50<RPN<100shouldasfaraspossibletosolve,can'tsolvemustbetightenedcontrol;RPN<50don'taddcontrol.Whentheseverity(S)orhighincidence(O)isveryhigh,nomatterhowRPNsizewillbeformulatethecorrespondingimprovementorcontrolmeasures,andappointresponsiblepersonsandimprovethecompletiondate.如何制定改改善措施Howtomaketheimprovementmeasures针对预防/纠正措施，以以降低评价价等级的内内容顺序为为：严重度度、发生率率及侦测度；；Aimingatpreventing/correctivemeasures,inordertoreducethecontentoftheevaluationgradeorder:(S),(O),(D).通过设计变变更来消除除或控制一一个或多个个失效模式式的起因机机理，能降降低严重度等级；；Throughthedesignchangetoeliminateorcontroloneormoreofthecauseofthefailuremodemechanism,canreducetheseveritylevel;透过设计变变更，去除除或管制某某一或多个个影响失效效模式的原原因或设备备，只能降低发生率率的等级.Throughthechangeofthedesign,removeorcontroloneormoreofthecauseofthefailuremodeeffectorequipment,canreducetheincidenceofgrade.增加设计验证证，修改测试试计划，修改改原物料规格格，只可降低低难检度.Toincreasethedesignverification,modifyingthetestplan,modifytheoriginalmaterialspecifications,canonlyreducethedifficultdegreeoftest.五、DFMEA表单填写说明明1

DFMEANotesoncompletingtheform(1)DFMEA编号：填入DFMEA文件的编号，，以便要询；；DFMEANumbers:fillintheDFMEAfileNumbers,sothattoinformation;项目：填入所所分析的系统统、子系统或或零件的过程程名称，编号号；Project:fillintheanalysisofthesystem,subsystemorpartsoftheprocessname,Numbers;设计责任：部部门、小组还还应包括供方方的名称；Designresponsibility:department,theteamalsoshouldincludethenameofthesupplier;填入负责DFMEA工作的工程师师姓名、电话话及所在公司司名称；FillintheresponsibleoftheengineersDFMEAname,phonenumberandthenameofthecompany;填入将使用或或正被分析的的设计过程影影响的预期的的机型和料号号；Fillinwilluseorarebeinganalyzedtheinfluenceofthedesignprocessoftheexpectedtypeandmaterialnumber;关键日期：填填入DFMEA初次预定完成成日期，该日日期不应超过过计划开始设设计生产发布布日期.Thekeydate:fillintheDFMEAfirsttargetcompletiondate,thisdateshallnotexceedthedesignplantobeginproductionreleasedate.五、DFMEA表单填写说明明2

DFMEANotesoncompletingtheform(2)DFMEA日期：填入编编制DFMEA原始稿的日期期及最新修订订日期；DFMEAdate:fillinthedrawupDFMEAdateandlatestrevisiondate.核心小组：列出出有权确定和和执行任务的的责任部门和和个人姓名，，如果对某一一特定原因无无建议措施，，那么就在该栏中写写“N/A”.Thecoreteam:listshallhavetherighttodetermineandimplementtheresponsibilityofthedepartmentandindividualtaskname,ifforAparticularreasonnosuggestedmeasures,thenwriteinthecolumnof"N/A".项目/功能：填入被被分析项目的的名称和编号号，若该项目目有多种功能能，且有不同同的失效模式式，应把所有有功都单独列出.Project/function:fillinthenameoftheprojectareanalyzedandNumbers,iftheprojecthasavarietyoffunctions,andhavedifferentfailuremode,weshouldputallfunctionsarelistedseparately.潜在失效模式式：对一个特特定项目及其其功能，应用用规范化，专专业性的术语语来列出每一一个潜在的失失效模式前提是这种失失效可能发生生，但不一定定发生.Potentialfailuremode:foraspecificprojectanditsfunction,theapplicationofstandardized,professionaltermstolisteachpotentialfailuremodeprovidedthatfailuremayoccur,butdoesnotnecessarilyoccur.五、DFMEA表单填写说明明3DFMEANotesoncompletingtheform(3)潜在失效后果果，就是失效效模式对系统统功能的影响响，一般是客客户在使用时时看到的状况况；Potentialfailureconsequences,isthefailuremodeoftheinfluenceofthesystemfunction,itistoseethecustomersintheuseofthesituation.严重度(S)Severity分级（重要程程序）用于对对零件、系统统、子系统的的产品特性分分