FMEA--失效模式分析

FMEAFAILUREMODEEFFECTSANALYSIS1FMEA2AnanalyticaltoolforidentifyingPotentialFailuresinaproductorprocesssothatcorrectiveactioncanbetakenbeforethefailurescanreachthecustomer.FMEA是一種識別產品或過程的潛在失效,以便在這些失效影響客戶之前採取措施的分析工具FMEA3AnFMEAisaStructuredApproachto:FMEA是結構式的方法•Identifyingthewaysinwhichadesignorprocesscanfailtomeetthecriticalcustomerrequirements識別設計或過程可能以何種方式失效而不能滿足客戶重要需求•Estimatingtheriskofspecificcauseswithregardtothesefailures估計產生這些失效的特殊原因的風險•Evaluatingthecurrentcontrolsforpreventingthesefailures評估現有控制手段對這些失效的預防•Prioritizingtheactionsthatmustbetakentoimprovethedesignortheprocess給那些用以改進設計和過程的措施排序FMEA4FMEA–History歷史Firstusedinthe1960’sduringtheApolloMoonMissions.最早被用於上世紀六十年代的阿波羅登月計劃.In1974MIL-STD-1629wasdevelopedbytheNavyforusingFMEA’s.1974年海軍為FMEA的應用制定了MIL-STD-1629.Inthelate1970,adaptedbytheautoindustryinresponsetohigherliabilitycostsandhigherqualitydemandsbycustomers.在二十世紀七十年代末,為滿足客戶更高的責任成本和質量需求而被用於自動化工業中.FMEA5FMEAisproactive,notreactive.Don'twaitforthecustomertocomplainifyoucanavoidit!FMEA是預防性的，不是反應性的。應當儘量避免失效，而不是等著顧客提出申訴！FMEA6FMEAreducesthechancethatacustomerwillseeafailureFMEA通過以下措施減少顧客遇到失效的情況:–Bydefiningfailureintermsofwhatthecustomerwantsandexpects.針對顧客的要求和期望確定失效–Byshowingwheremeasuresneedtobetakentopreventfailure.指出爲了防止失效，需要在哪方面採取措施FMEA7TypesofFMEAs類型Design–usedtoanalyzeproductdesignsbeforetheyarereleasedtoproduction設計-用於在產品投產前對設計的分析Process–usedtoanalyzemanufacturingprocesses過程-用於分析製程System–usedtoanalyzesystemsintheearlyconceptanddesignstages系統–用於分析早期的概念和設計階段的系統FMEA8Summary概要–Identifiesknownandpotentialfailuremodes;識別已知和潛在的失效模式–Identifiesthecausesandeffectsofeachfailuremode;識別每一種失效模式的原因和後果–Prioritizesthefailuremodes(usingtheRPN);利用風險序數（RPN）給失效模式排序–Shouldinitiatecorrectiveactionwhereneeded.必要時提出糾正措施FMEA9TimingofanFMEAFMEA的時機FMEA’sshouldbeinitiatedwhenpreliminarydrawingsofthedesignorprocessareavailable當初步的設計圖紙和工藝被制定出來時應開始做FMEAUpdatedasidentifiedissuesareresolved當被發現的問題解決後要更新FMEACanbeusedonexistingproductstoimprovequality可用於現有的產品以提高質量FMEA10System系統–Wiringharness線束–Electronicmodule電控模塊–Assembly總成SystemFMEAtreatssystemasa“functionalschematic”系統FMEA從“功能關係圖”入手來考慮FMEA11Ananalyticaltoolusedtoidentifysystem-levelfailuremodes,andidentifycorrectiveactionstobetaken.是一種分析工具用來識別系統失效模式FMEA12ItissimilartoaDesignFMEA,butfocusesonthecircuitschematicinsteadofphysicalfailureofcomponents.同DFMEA相類似,系統FMEA側重於回路設計而不是元件的物理失效。Takeelectricalsystemsasexamples.以電氣系統為例。FMEA13Example:舉例：Failuremodeatelectricalsystemlevel電氣系統失效模式–OpencircuitatcktA回路A出現開路Cause:原因：–Terminalunseated端子脫出Terminalunseatedbecomesafailuremodeatthecomponentlevel.端子脫出是電氣元件的失效模式。FMEA14RulesofDesignFMEA設計FMEA規則Toolfordesignengineersandprojectteamtoimprovethedesigninapreemptivemanner(beforefailureoccur)是設計工程師和項目小組的工具用來提高設計的前瞻性(在問題發生前)UsedtoestablishedCriticaltoQualityfeaturesthateffecttheperformanceoftheproduct用與那些影響產品性能的重要質量特性UsedtoestablishCriticaltoLifefeaturesthateffectthelifeoftheproduct用於確定影響產品壽命的重要壽命特性UsedtoestablishCriticaltosafetyfeatures用於確定重要安全特性FMEA15PurposeofDesignFMEA設計FMEA的用途Establishescriticalfeaturesthatmustbecontrolledinmanufacturingtosatisfycustomerrequirements確定那些必須在生產中進行控制的特性以滿足客戶要求Identifiesdeficienciesintheproductdesignandassociatedactionitems找出產品設計中的不足和相應的措施Helpsevaluatetheriskofdesignchanges幫助評價設計變更的風險FMEA16PurposeofDesignFMEA設計FMEA的用途Identifiesprocessdevelopmentneeds確定開發工藝流程的需求Dynamicdocument–documentsdesignalternativesandassociatedrisks動態的文件–記錄可選擇的設計方案和相應的風險Establishesbasesformanufacturingandqualitycontrolplan建立製造和品質控制計劃的基礎FMEA17DesignFMEAInputsandOutputs設計FMEA的輸入和輸出•Productdrawings產品圖紙•Productmodels產品模型•Productspecification產品規格•IdentifiedCriticaltoQualityfailures確定的重要質量特性•Actionstopreventthecausesoffailures防止失效原因的措施•Actionstodetectfailuremodes發現失效模式的措施•HistoryofactionsandResponsibilities措施和責任人的記錄FMEA18Design设计–Components元件–Elements设计要素DesignFMEAlooksatphysicalfailuremodesofcomponentsanddesignelements设计FMEA着眼于元件及设计要素的物理失效模式FMEA19RulesofProcessFMEA過程FMEA規則Toolforprocessengineersandprojectteamtoimprovethemanufacturingprocessinapreemptivemanner是工藝工程師和項目小組的工具,用來提高製造工藝的前瞻性Usedtoprioritizeactionstoensureattentiontocriticalprocessesthateffectcustomers用與區分先後順序以確保那些影響客戶的重要工藝Usedtodocumentprocessimprovements用於工藝改進Dynamicdocumentforcontinuousimprovement持續改進的動態文件FMEA20PurposeofProcessFMEA過程FMEA的用途Assistsintheanalysisofnewmanufacturingprocess幫助分析新的製造工藝Establishesthebasesformanufacturingprocessinstructionsandcontrolsheets建立製造工藝文件和控制文件的基礎Identifiesnewmanufacturingprocessneeds確定新製造工藝的需求Helpsevaluatetheriskofprocesschanges幫助評估工藝更改的風險FMEA21Process过程–Manufacturing制造–Assembling装配ProcessFMEAlooksatproductfailurescausedbytheprocessfailingtomeetrequirements过程FMEA着眼于因加工過程不符合要求所造成的产品失效FMEA22FMEATeam小組Teamapproachisnecessary.需要團隊的方式ResponsibleforDesignFMEA–DesignEngineer設計工程師負責設計FMEAResponsibleforProcessFMEA–ManufacturingEngineer製造工程師負責過程FMEARecommendedrepresentatives:推薦人選:–Design/設計–ManufacturingEngineers/製造工程師–QualityEngineers/質量工程師–Reliability/可靠性–Materials/原材料–Suppliers/供應商FMEA23DefinitionofTerms術語FailureMode–Thewayin