【正文】 OccurrenceP o t e n t i a l F a i l u r e M o d eP o t e n t i a l E f f e c t ( s ) o f F a i l u r eP o t e n t i a l C a u s e s ( s )o f F a i l u r eP O TE N TI A LFA I LU R E M O D E A N D E FF E C TS A N A LY S I S( D E S I G N FM E A )FM 0 0 0 1C u r r e n tD e s i g nC o n t r o l sP r e v e n t i o nC u r r e n tD e s i g nC o n t r o l sD e t e c t i o nDetectionRPN R e c o m m e n d e d A c t i o nB e t h R o w e nR e s p o n s i b i l i t y T a r g e t C o m p l e t i o n D a t eA c t i o n R e s u l t s34 路徑 /步驟 1關(guān)鍵特性（ CC）傳遞例 關(guān)鍵特性 (Critical Characteristics )由 (▼ )表示，是指對(duì)產(chǎn)品的要求（尺寸，性能，試驗(yàn)等）或指生產(chǎn)工藝參數(shù)（速率，溫度，壓力等）。 這個(gè)例子中，有兩個(gè)問(wèn)題： ?這個(gè)真的是 YC特性嗎？ ?這個(gè)特殊特性具體指的產(chǎn)品特性是什么？ DFMEA PFMEA STA Team, Changan Ford Mazda Co. 路徑 /步驟 1建議的措施 Process Function Requirements POTENTIAL FAILURE MODE AND EFFECTS ANALYSIS Potential Failure Mode O c c u r Current Controls Remended Action(s) Responsibility Target Completion Date Action Results Actions Taken Prevention Detection What How often does it happen? C l a s s S e v Potential Effect(s) of Failure Potential Cause(s)/ Mechanism(s) of Failure D e t e c R. P. N. R. P. N. D e t O c c S e v What are the Functions, Features or Requirements? What are the Effect(s)? How bad is it? ? No Function ? Partial/ Over Function/Degraded Over Time ? Intermittent Function ? Unintended Function What can go wrong? ? Design Changes ? Process Changes ? Special Controls ? Changes to Standards, Procedures, or Guides What can be done? ? 如果可能，在 “原因”沒(méi)有識(shí)別前推薦行動(dòng)去消除失效模式 ? 這是非常罕見的。 STA Team, Changan Ford Mazda Co. SummaryBreak ? FMEA基礎(chǔ)知識(shí) ? PFMEA的輸入 ? PFMEA路徑 /步驟 1 ? 過(guò)程功能 /要求 ? 潛在失效模式 ? 潛在 失效后果 ? 嚴(yán)重度 ? 特殊特性與特別控制 STA Team, Changan Ford Mazda Co. 如何開發(fā) PFMEA？ 路徑 /步驟 2 Process Function Requirements POTENTIAL FAILURE MODE AND EFFECTS ANALYSIS Potential Failure Mode O c c u r Current Controls Remended Action(s) Responsibility Target Completion Date Action Results Actions Taken Prevention Detection What How often does it happen? C l a s s S e v Potential Effect(s) of Failure Potential Cause(s)/ Mechanism(s) of Failure D e t e c R. P. N. R. P. N. D e t O c c S e v are the Cause(s)? ? Design Changes ? Process Changes ? Special Controls ? Changes to Standards, Procedures, or Guides What can be done? 第二步： ?潛在的原因 （第一級(jí)到根本原因） ?發(fā)生率等級(jí)。 ?為高嚴(yán)重度和高風(fēng) 險(xiǎn)度（ S x O）， 也為操作人員安全（ OS）和過(guò)程出錯(cuò)高風(fēng)險(xiǎn)（ HI）的推薦行動(dòng)。 例如： ? 原材料的機(jī)械性能 ? 原材料厚度 ? 領(lǐng)取零件孔徑大小 ? 領(lǐng)取零件面輪廓度 假設(shè)二：來(lái)料（零件 /原料）是有問(wèn)題的，這主要在零件 /原料采購(gòu)過(guò)程考慮。 ? 問(wèn)“這失效模式會(huì)造成什么后果？” 答案就是失效后果。 STA Team, Changan Ford Mazda Co. 路徑 /步驟 2現(xiàn)行過(guò)程預(yù)防控制 Process Function Requirements POTENTIAL FAILURE MODE AND EFFECTS ANALYSIS Potential Failure Mode O c c u r Current Controls Remended Action(s) Responsibility Target Completion Date Action Results Actions Taken Prevention Detection What How often does it happen? C l a s s S e v Potential Effect(s) of Failure Potential Cause(s)/ Mechanism(s) of Failure D e t e c R. P. N. R. P. N. D e t O c c S e v ? Design Changes ? Process Changes ? Special Controls ? Changes to Standards, Procedures, or Guides What can be done? How good is this method at detecting it? How can this be prevented and detected? 當(dāng)前的過(guò)程預(yù)防性控 制（設(shè)計(jì)和 /或過(guò)程行動(dòng)） 用于確定發(fā)生度 。 STA Team, Changan Ford Mazda Co. 路徑 /步驟 2現(xiàn)行過(guò)程預(yù)防控制例 過(guò)程步驟 功能 要求 潛在失效模式 失效潛在 原因 現(xiàn)行過(guò)程 控制預(yù)防 凸焊螺母（ M8） 焊接強(qiáng)度滿足ESBM5A_1N265_AA標(biāo)準(zhǔn)要求 虛焊、弱焊 參數(shù)設(shè)置不合理 班前參數(shù)檢查 試片試驗(yàn) 冷卻水流量不足 安裝報(bào)警器：使凸焊時(shí)水流量不足焊機(jī)自動(dòng)停止 分流 對(duì)分流處進(jìn)行絕緣或讓位處理 電極不平整或未對(duì)中 班前設(shè)備檢查、定期修磨電極 STA Team, Changan Ford Mazda Co. 路徑 /步驟 2發(fā)生度 Process Function Requirements POTENTIAL FAILURE MODE AND EFFECTS ANALYSIS Potential Failure Mode O c c u r Current Controls Remended Action(s) Responsibility Target Completion Date Action Results Actions Taken Prevention Detection What How often does it happen? C l a s s S e v Potential Effect(s) of Failure Potential Cause(s)/ Mechanism(s) of Failure D e t e c R. P. N. R. P. N. D e t O c c S e v ? No Function ? Partial/ Over Function/Degraded Over Time ? Intermittent Function ? Unintended Function What can go wrong? are the Cause(s)? ? Design Changes ? Process Changes ? Special Controls ? Changes to Standards, Procedures, or Guides What can be done? ? 定義：發(fā)生度是針對(duì)在特殊 原因下發(fā)生的可能性， 是一個(gè)相對(duì)值而非絕 對(duì)值。 若原因發(fā)生 率不能被評(píng)估，那就評(píng)估潛在失效率。） ? 對(duì)原因 /失效模式的預(yù)防控制只能通過(guò)設(shè)計(jì)或者過(guò)程變更，這是降低發(fā)生度的唯一方法。 高影響特性：當(dāng)產(chǎn)品或過(guò)程特性超出公差規(guī)范時(shí)，就會(huì)嚴(yán)重影響過(guò)程本身的操作或后續(xù)的操作（不要求特別控制）。 ? Addition of consideration of the influence of the manufacturing process before the designation of a YS 在確定為 YS之前，需要額外考慮其是否會(huì)受到制造過(guò)程影響； ? Ability to designate a characteristic as a YS with severity less than 5 if agreed by the cross functional team ? 如果各相關(guān)部門一致同意，與嚴(yán)重度小于 5失效模式相關(guān)的特性也可被歸為 YS。 6 CTQ 參數(shù)設(shè)置不合理 班前參數(shù)檢查 試片試驗(yàn) 3 冷卻水流量不足 安裝報(bào)警器：使凸焊時(shí)水流量不足焊機(jī)自動(dòng)停止 分流 對(duì)分流處進(jìn)行絕緣或讓位處理 電極不平整或未對(duì)中 班前設(shè)備檢查、定期修磨電極 STA Team, Changan Ford Mazda Co. 路徑 /步驟 2重要特性（ SC）傳遞例 過(guò)程 /功能要求 潛在的失效模式 潛在失效后果 S 級(jí)別 潛在失效原因 /機(jī)理 O 組件 (……177。例如造成腐蝕的原因，塑料在制造過(guò)程中不受影響，而金屬會(huì)，若設(shè) 計(jì)選擇塑料，那過(guò)程中的變差怎么也不會(huì)導(dǎo)致塑料腐蝕。 ? SCs may be identified in the PFMEA, without alignment to a YS in the DFMEA, as long as they satisfy the PFMEA SC Criteria . PFMEA中確定的 SCs，不一定會(huì)對(duì)應(yīng)于 DFMEA中的某個(gè) YS，只要其能滿 足 PFMEA中 SC的標(biāo)