失效模式分析（共68）.ppt

1、FMEAFAILURE MODE EFFECTS ANALYSIS1FMEAFMEA2An analytical tool for identifying in a product or process so that corrective action can be taken FMEAFMEA是一種識別產(chǎn)品或過程的潛在失潛在失效效,以便在這些失效影響客戶之前在這些失效影響客戶之前 採取措施的分析工具FMEAFMEA3 FMEAFMEA4FMEA History 歷史歷史n First used in the 1960s during the Apollo Moon Missions.最早被

2、用於上世紀(jì)六十年代的阿波羅登月計劃.n In 1974 MIL-STD-1629 was developed by the Navy for using FMEAs.1974年海軍為FMEA的應(yīng)用制定了MIL-STD-1629.n In the late 1970, adapted by the auto industry in response to higher liability costs and higher quality demands by customers.在二十世紀(jì)七十年代末, 為滿足客戶更高的責(zé)任成本和質(zhì)量需求而被用於自動化工業(yè)中.FMEAFMEA5FMEAFMEA6F

3、MEA reduces the chance that a customer will see a failureFMEA通過以下措施減少顧客遇到失效的情況: By defining failure in terms of what the customer wants and expects.針對顧客的要求和期望確定失效 By showing where measures need to be taken to prevent failure.指出爲(wèi)了防止失效，需要在哪方面採取措施 FMEAFMEA7Types of FMEAs 類型類型nDesign used to analyze pro

4、duct designs before they are released to production設(shè)計 - 用於在產(chǎn)品投產(chǎn)前對設(shè)計的分析n Process used to analyze manufacturing processes過程 - 用於分析製程n System used to analyze systems in the early concept and design stages系統(tǒng) 用於分析早期的概念和設(shè)計階段的系統(tǒng)FMEAFMEA8Summary 概要概要 Identifies known and potential failure modes;識別已知和潛在的失效模式

5、 Identifies the causes and effects of each failure mode;識別每一種失效模式的原因和後果 Prioritizes the failure modes (using the RPN); 利用風(fēng)險序數(shù) （RPN）給失效模式排序 Should initiate corrective action where needed.必要時提出糾正措施FMEAFMEA9FMEAFMEA10nSystem系統(tǒng)系統(tǒng) Wiring harness 線束線束 Electronic module電控模塊電控模塊 Assembly總成總成FMEAFMEA11FMEAFM

6、EA12FMEAFMEA13FMEAFMEA14Rules of Design FMEA設(shè)計設(shè)計FMEA規(guī)則規(guī)則n Tool for design engineers and project team to improve the design in a preemptive manner (before failure occur)是設(shè)計工程師和項目小組的工具用來提高設(shè)計的前瞻性(在問題發(fā)生前)n Used to established Critical to Quality features that effect the performance of the product用與那些影響產(chǎn)

7、品性能的重要質(zhì)量特性n Used to establish Critical to Life features that effect the life of the product用於確定影響產(chǎn)品壽命的重要壽命特性n Used to establish Critical to safety features用於確定重要安全特性FMEAFMEA15FMEAFMEA16FMEAFMEA17 Product drawings產(chǎn)品圖紙產(chǎn)品圖紙 Product models產(chǎn)品模型產(chǎn)品模型 Product specification產(chǎn)品規(guī)格產(chǎn)品規(guī)格 Identified Critical toQual

8、ity failures確定的重要質(zhì)量特性確定的重要質(zhì)量特性 Actions to prevent the causes of failures防止失效原因的措施防止失效原因的措施 Actions to detect failure modes發(fā)現(xiàn)失效模式的措施發(fā)現(xiàn)失效模式的措施 History of actions and Responsibilities措施和責(zé)任人的記錄措施和責(zé)任人的記錄FMEAFMEA18nDesign 設(shè)計設(shè)計 Components 元件元件 Elements設(shè)計要素設(shè)計要素FMEAFMEA19Rules of Process FMEA過程過程FMEA規(guī)則規(guī)則n To

9、ol for process engineers and project team to improve the manufacturing process in a preemptive manner 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n Used to prioritize actions to ensure attention to critical processes that effect customers用與區(qū)分先後順序以確保那些影響客戶的重要工藝nUsed to document process improvements用於工藝改進n Dynamic doc

10、ument for continuous improvement持續(xù)改進的動態(tài)文件FMEAFMEA20FMEAFMEA21nProcess 過程過程 Manufacturing 制造制造 Assembling裝配裝配FMEAFMEA22FMEA Team 小組小組n Team approach is necessary.需要團隊的方式n Responsible for Design FMEA Design Engineer設(shè)計工程師負(fù)責(zé)設(shè)計FMEAn Responsible for Process FMEA Manufacturing Engineer製造工程師負(fù)責(zé)過程FMEAn Recomm

11、ended representatives:推薦人選: Design / 設(shè)計 Manufacturing Engineers / 製造工程師 Quality Engineers / 質(zhì)量工程師 Reliability / 可靠性 Materials / 原材料 Suppliers / 供應(yīng)商FMEAFMEA23Definition of Terms 術(shù)語術(shù)語nFailure Mode The way in which a specific input requirement fails and if not detected, corrected or removed will cause

12、an Effect to occur.失效模式失效模式 一個特殊的輸入要求失敗的方式或者由於未被發(fā)覺,糾正或消除而帶來的後果n Effect Impact on customer requirements 後果後果 對客戶要求的影響FMEAFMEA24Definition of Terms 術(shù)語術(shù)語nCause Source(s) of process variation that causes the Failure Mode to occur.原因原因 造成失效模式發(fā)生的過程變差的起源n Current Control (proposed controls)當(dāng)前的控制當(dāng)前的控制 (建議的控

13、制) Design elements that ensure function確保功能的設(shè)計要素 Mistake proofing, automated controls, set up instructions, gauges防錯,自動化控制,機器設(shè)定指導(dǎo)書,量具 Audits, checklists, inspections, PM, etc.稽核,檢查表,檢驗,設(shè)備維護,等FMEAFMEA25Failure Mode 1Failure Mode 2Effect 1Failure Mode 1Effect 2Effect 1Failure Mode 1Failure Mode 2Effec

14、t 1Note that the relationship between the Failure Mode and Effect is not always 1-to-1 請注意失效模式和後果之間的關(guān)係不總是一對一請注意失效模式和後果之間的關(guān)係不總是一對一Effect 2FMEAFMEA26Risk Priority Number 風(fēng)險序數(shù)風(fēng)險序數(shù)n The output of a FMEA is the “Risk of Priority Number” - RPN一個FMEA的輸出是“風(fēng)險序數(shù)”-RPN n The RPN is a calculated number based on

15、information provided regardingRPN是根據(jù)下面的資料計算出來的 The potential failure modes,潛在失效模式 The effects, and後果 The current or planned ability to detect the failure before it reaches the customer現(xiàn)有的和已計劃的能力可以在影響客戶前覺察失效FMEAFMEA27Risk Priority Number 風(fēng)險序數(shù)風(fēng)險序數(shù)n It is calculated as the product of three quantitative

16、 rating 它是用三個級數(shù)計算出來的RPN = Severity * Occurrence * Detection風(fēng)險序數(shù)風(fēng)險序數(shù) = 嚴(yán)重度嚴(yán)重度 * 發(fā)生頻度發(fā)生頻度 * 探測度探測度n The RPN is not sacredRPN不是神聖的n Scaling for Severity, Occurrence, and Detection are locally developed嚴(yán)重度,發(fā)生頻度,探測度的尺度由自己制定n Other categories may be added to suit need根據(jù)需要可以加上其他類型n High Risk Priority Numbe

17、rs are significant to the success of the product design - actions must be taken to prevent failures高風(fēng)險序數(shù)對產(chǎn)品設(shè)計的成功來講很重要 - 需要採取措施來防止失效FMEAFMEA28Definition of RPN Terms RPN術(shù)語術(shù)語nSeverity (of effect) Importance to customer, may involve function, safety, reliability, or life of product (1= not severe, 10 =

18、 very severe)嚴(yán)重度嚴(yán)重度(後果的後果的) 對客戶的重要程度, 可包括功能,安全,可靠性, 產(chǎn)品壽命等方面. (1=不嚴(yán)重, 10=很嚴(yán)重)n Occurrence (of cause) Frequency with which a given Cause may occur (1= not likely to occur, 10= very likely to occur)發(fā)生頻度發(fā)生頻度 (原因的原因的) 一個特定的原因可能發(fā)生的頻度 (1= 不可能發(fā)生, 10= 很可能發(fā)生)nDetection (Capability of current or planned Contro

19、ls) Ability to detect the cause (1= likely to be detected, 10= not likely to be detected)探測度探測度 (現(xiàn)有的或已計劃的控制能力現(xiàn)有的或已計劃的控制能力) 覺察原因的能力 (1= 有可能發(fā)覺, 10= 不可能發(fā)覺)FMEAFMEA29Rating得分 Degree of Severity/ 嚴(yán)重程度 1Customer will not notice the adverse effect or it is insignificant/客戶不會注意到或該不利後果不重要 2Customer will prob

20、ably experience slight annoyance/可能對客戶有輕微的影響3Customer will experience annoyance due to the slight degradation of performance/由於輕微的性能下降可能給客戶帶來麻煩 4Customer dissatisfaction due to reduced performance/由於性能下降使客戶不滿意 5Customer is made uncomfortable or their productivity is reduced by the continued degradat

21、ion of the effect/客戶不滿意或受持續(xù)降級的影響使他們的生產(chǎn)力降低 6Warranty repair or significant manufacturing or assembly complain/保修或者重大的製造或組裝的投訴 7High degree of customer dissatisfaction due to component failure without complete loss of function. Productivity impacted by high scrap or rework levels/零件雖未完全失去功能但引起客戶較大的不滿;

22、由於高報廢,高返工率影響生產(chǎn)力 8Very high degree of customer dissatisfaction due to the loss of function without a negative impact on safety or government regulation/由於零件喪失功能而引起客戶極大不滿但尚未違反安全或國家規(guī)定 9Customer endangered due to adverse effect on safe system performance with warning before failure or violation of gover

23、nmental regulations/安全系統(tǒng)的不利影響使得客戶處於危險當(dāng)中但在失效前有警告或違反國家規(guī)定 10Customer endangered due to adverse effect on safe system performance without warning before failure or violation of governmental regulations/安全系統(tǒng)的不利影響使得客戶處於危險當(dāng)中而且失效前沒有警告或違反國家規(guī)定 FMEAFMEA30Rating得分 Likelihood of Occurrence/ 發(fā)生的可能性1Likelihood of

24、occurrence is remote/ 發(fā)生的可能性極小2Low failure rate with support documentation/ 有書面證據(jù)證明發(fā)生的可能性很低3Low failure rate without support documentation/發(fā)生的可能性很低但沒有書面證據(jù)證明4Occasional failure/ 偶爾失效5Relatively Moderate failure rate with supporting documentation/有書面證據(jù)證明中等的失效可能性6Moderate failure rate without supportin

25、g documentation/沒有書面證據(jù)證明中等的失效可能性7Relatively high failure rate with supporting documentation/有書面證據(jù)證明高度的失效可能性8Relatively high failure rate without supporting documentation/沒有書面證據(jù)證明高度的失效可能性9Failure is almost certain based on warranty data or significant testing/ 根據(jù)保修數(shù)據(jù)或重要試驗幾乎可以肯定失效會發(fā)生10Assure of Failur

26、e based on warranty data or significant testing/ 根據(jù)保修數(shù)據(jù)或重要試驗可以肯定失效會發(fā)生FMEAFMEA31Rating得分 Ability of Detect/ 可探測度 1Sure that the potential failure will be found or prevented before reaching the next customer/確定潛在失效可以在到達下一個客戶前被發(fā)現(xiàn)或預(yù)防2Almost certain that the potential failure will be found or prevented b

27、efore reaching the next customer/幾乎可以肯定潛在失效可以在到達下一個客戶前被發(fā)現(xiàn)或預(yù)防3Low likelihood that the potential failure will reach the next customer/潛在的失效到達下一個客戶的可能性很低4Controls may detect or prevent the potential failure from reaching the next customer/控制手段可以防止?jié)撛谑У竭_下一個客戶5Moderate likelihood that the potential failu

28、re will reach the next customer/潛在的失效到達下一個客戶的可能性中等6Controls are likely to detect or prevent the potential failure from reaching the next customer/控制手段不太可能防止?jié)撛谑У竭_下一個客戶7Poor likelihood that the potential failure will be detected or prevented before reaching the next customer/在潛在失效到達下一個客戶前發(fā)現(xiàn)或預(yù)防的可能性較低8

29、Very poor likelihood that the potential failure will be detected or prevented before reaching the next customer/在潛在失效到達下一個客戶前發(fā)現(xiàn)或預(yù)防的可能性非常低9Current controls probably will not detect the potential failure/現(xiàn)有控制手段可能探測不到潛在失效10Absolute certainly that the current controls will not detect the potential failu

30、re/完全肯定現(xiàn)有的控制手段無法探測潛在失效FMEAFMEA32Scale Value分值Occurrences perWeek週Day日Shift班Hour小時1070010033495007124383505017272002910161001451575114450723254127111FMEAFMEA33Scale Value/分值分值Percent of potential failures prevented預(yù)防潛在失效的比率預(yù)防潛在失效的比率190%280%370%460%550%640%730%820%910%100%FMEAFMEA34ProcessStep/InputPo

31、tential Failure ModePotential Failure EffectsSEVPotential CausesOCCCurrent ControlsDETRPNActions Recommended0000000000000000FMEAFMEA35FMEA FAILURE MODE EFFECTS ANALYSISProduct:ProcessStep/InputPotential Failure ModePotential Failure EffectsSEVPotential CausesOCCCurrent ControlsDETRPNActions Recommen

32、dedResponsibilityWhat is the step or input under investigation?In what way does the key input go wrong?What is the impact on the key output variable (customer requirement or internal requirement)How severe is the impact on the customer?What causes the key output to go wrong?How often does cause of f

33、ailure mode happen?What are the existing controls and procedures (inspection and testing) that prevent either the cause or the failure mode? Include shop operating procedure number How well can the failure mode of cause be detected?RPN = SEV * OCC * DETWhat are the actions for reducing the occurrenc

34、e of the cause or improving detection? Should have actions on all high RPN numbers.Who is responsible for implementing the recommended actions?0000FMEAFMEA36Prevention/預(yù)防預(yù)防Prevention/預(yù)防預(yù)防Prevention/預(yù)防預(yù)防Cause/原因原因Effect/後果後果Failure Mode/失效模式失效模式Controls/控制控制Material or process input/原料或過程輸入原料或過程輸入Pro

35、cess Step/工序工序External customer or downstream process step/外部客戶或下一外部客戶或下一工序工序FMEAFMEA37General Steps in the DFMEA/一般步驟n Select design FMEA team 組建設(shè)計FMEA小組nList customer requirements 列出客戶的要求n For each customer requirement list the key design elements that satisfy the customer requirements 針對客戶的每一個要求列

36、出滿足該要求的關(guān)鍵設(shè)計要素n For each key design element list ways that the design element could vary, Potential Failure Modes 列出每一個關(guān)鍵設(shè)計要素的變化,潛在的失效模式n List Effects of each Failure mode on the customer requirement 列出每個失效模式的對客戶要求的影響n List Causes for each failure Mode 列出失效模式的原因FMEAFMEA38General Steps in the DFMEA/一般

37、步驟n List current controls for each cause 列出每個原因的現(xiàn)有控制手段n Assign Severity, Occurrence, and Detection ratings to each cause給每個原因的嚴(yán)重度,頻度,可探測度評分n Calculate RPNs 計算風(fēng)險序數(shù)n Recommend actions to reduce high RPNs 提出降低風(fēng)險序數(shù)的措施n Take appropriate action 採取適當(dāng)?shù)拇胧﹏ Recalculate RPNs 重新計算風(fēng)險序數(shù)FMEAFMEA39FMEAFMEA40Compone

38、nt元件元件Component元件元件Component元件元件Component元件元件Component元件元件Component元件元件Examples例如FMEAFMEA41List The Function(s) of Each Component列出每個要素的功能列出每個要素的功能FMEAFMEA42FMEAFMEA43FMEAFMEA44FMEAFMEA45FMEAFMEA46FMEAFMEA47FMEAFMEA48FMEAFMEA49FMEAFMEA50 FMEAFMEA51General Steps in the PFMEA/一般步驟n Select process FMEA team 組建過程FMEA小組n Develop a Process Map and identify all process steps 做一個流程圖確定過程的所有步驟n List all the Key Process Outputs to satisfy internal and external customer requirement 列出所有的滿足內(nèi)部和外部客戶要求的關(guān)鍵過程輸出n For each process step, list Key Pr