【文章內(nèi)容簡(jiǎn)介】 ated as:Cp = USL LSL 6? Cp = Referred to as capability index　 過程能力指數(shù)過程能力指數(shù) 7. 2. 4 Capability Indices 過程能力指數(shù)30StepByStep Approach To Performing A Process Capability Study過程能力分析的步驟 (例：制造 ) 　Z (minimum) is equal to the smaller of the two valuesZ (upper) = USL – Process Average　　 　　 3 ? Z (lower) = Process Average – LSL 3 ?Cpk 既反映過程的精密度又反映其既反映過程的精密度又反映其 均值與目標(biāo)的偏離均值與目標(biāo)的偏離　 Calculated as:　 CPK = Z (Smaller) 3 ?Cpk = Referred to as capability index 實(shí)際過程能力指數(shù)實(shí)際過程能力指數(shù)7. 2. 4　 Capability Indices 過程能力指數(shù)31The Relation Between Cp And Cpk實(shí)際過程能力與潛在過程能力的關(guān)系實(shí)際過程能力與潛在過程能力的關(guān)系Cp = Cpk Process is well centeredCpk CpProcess is not properly centered 過程設(shè)定準(zhǔn)確，均值與目標(biāo)值重合過程未能準(zhǔn)確設(shè)定32 Example: Filling Process Capability Study Specification: Target 　　　 = KgLower Specification Limit(LSL) = KgUpper Specification Limit(USL) = KgSample Data:1. 9. 17. 25. 2. 10. 18. 26. 3. 11. 19. 27. 4. 12. 20. 28. 5. 13. 21. 29. 6. 14. 22. 30. 7. 15. 23. 31. 8. 16. 24. 32. Sample number = 32 Sample average = Standard deviation = Kg Accuracy = kg (與目標(biāo)值一致）Example: Capability Study Of Syrup Filling Process (Hypothetical)例：糖漿灌注過程能力分析 (假設(shè)）33Example: Capability Study Of Syrup Filling Process (Hypothetical)例：糖漿灌注過程能力分析 (假設(shè) )產(chǎn)品規(guī)格USL產(chǎn)品規(guī)格LSL規(guī)格范圍 kg 20 kg(目標(biāo) ) kg kg34Example: Capability Study Of Syrup Filling Process (Hypothetical)例：糖漿灌注過程能力分析 (假設(shè) )Histogram 　 直方圖R (樣品范圍 ) =最高值－最低值= kg－ kg= kgW (區(qū)間寬度） = R/ε(分辨率 ) = kgCS (起始值 ) = – () =179725 kg (分組數(shù)） = ＝６　= = kg ≈ kg各分組的上限值35Example: Capability Study Of Syrup Filling Process (Hypothetical)例：糖漿灌注過程能力分析 (假設(shè) )36Example: Capability Study Of Syrup Filling Process (Hypothetical)例：糖漿灌注過程能力分析 (假設(shè) )Capability Indices 能力指數(shù)Potential Capability Index (Cp) 潛在能力指數(shù)Cp = ( – ) 247。 (6 x ) = Actual Capability Index (Cpk) 實(shí)際能力指數(shù)Cpk = Z (Smaller) Z (Upper) = ( – ) 247。 ( x 3) = Z (Lower) = ( – ) 247。 ( x 3) = 37Example: Capability Study Of Syrup Filling Process (Hypothetical)例：糖漿灌注過程能力分析 (假設(shè) )The process is approximately normally distributed. It is both precise and perfectly centered.數(shù)據(jù)分析和計(jì)算表明數(shù)據(jù)分析和計(jì)算表明 ,過程基本為正態(tài)分布過程基本為正態(tài)分布 ,且精密度較高，且精密度較高，目標(biāo)值設(shè)定準(zhǔn)確目標(biāo)值設(shè)定準(zhǔn)確 (Cp與與 Cpk相等）．相等）．是有能力的過程．是有能力的過程． 　　目標(biāo) ?。?σ　　 －３ σ規(guī)格下限 規(guī)格下限38 TYPES OF CONTROL CHARTS 常用控制圖的類型常用控制圖的類型?Controls charts monitoring changes in process accuracy 監(jiān)控過程準(zhǔn)確度的變化Xcharts (Individual Observation Chart) 單值圖Xbarcharts 均值圖Pcharts 百分率圖 ?Control charts monitoring changes in process precision 監(jiān)控控過程精密度的變化Rbarcharts (Moving Range Charts) 移動(dòng)極差圖Scharts 標(biāo)準(zhǔn)差圖39Example: Capability Study Of Syrup Filling Process Run Charts 單值圖1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31Container Weight ( Kg )UCLx=Xbar=LCLx=Test OrderIndividual ValuesSample MeanUCLx and LCLxXchart for Process Capability Study 能力分析單值圖UCL — 控制范圍上限LCL — 控制范圍下限＋３ σ－ ３ σ40 Example: Capability Study Of Syrup Filling Process MR Chart 移動(dòng)極差圖移動(dòng)極差圖 Moving Range Chart for Process Capability Study 能力分析移動(dòng)極差圖2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32Test OrderRmRm barUCLm and LCLmRmiUCLm=Rmbar=LCLm=UCL — 控制范圍上限LCL — 控制范圍下限41 Control Charts Should Be Used in Pairs 控制圖的應(yīng)用組合An appropriate bination of control charts for continuously monitoring the process average and process variability 用于連續(xù)控制過程均值及離散性的控制圖組合用于連續(xù)控制過程均值及離散性的控制圖組合Acceptable choice would be X MR, Xbar R, or Xbar S charts.Control charts should always be prepared and analyzed in