SPC统计技术流程控制--stevexinli.ppt

1、,统计技术流程控制Statistical Process Control for Operators,惠亚集团SPC课程 A Workshop from Our Worldwide SPC Curriculum,SPC for Operators - Version 2.1 Mar. 10, 2001,2,培训目的Training Goal,目的-助你获得SPC的知识及技巧 Our Goal - To help you gain relevant SPC knowledge 多久收集一次? When do we collect it; how often? 流程中哪处收集数据? Where i

2、n the process do we get the data? 谁收集数据? Who collects the data?,SPC for Operators - Version 2.1 Mar. 10, 2001,18,什么数据需要收集?What data do we collect?,SPC for Operators - Version 2.1 Mar. 10, 2001,19,为什么需要收集数据?Why should we collect the data?,监控变异 To monitor variation. 尽早指出流程问题 To identify process proble

3、ms as early as possible.,为什么? Why?,SPC for Operators - Version 2.1 Mar. 10, 2001,20,如何收集数据?How do we collect the data?,如何? How?,收集数据 Collect data,我们需要一个测量系统 We need a measurement system.,方法-技巧,工具,经培训的员工 Method - technique, tool, trained people 记录-数据收集表格,表达数据的格式(即控制图) Record - data collection sheet,

4、format to present data (i.e., control chart) 计划-负责人,收集数据地点,频率,时间 Plan - who, where, how often, when,SPC for Operators - Version 2.1 Mar. 10, 2001,21,何时及何处收集数据?When & where do we get the data?,那一个比较好? Which is better?,流程中作测量 Measure on-line,最后检查 Inspect at end,SPC for Operators - Version 2.1 Mar. 10,

5、 2001,22,何时收集数据?When do we collect the data?,流程中作测量 Measure On-line, During the Process SPC SPC 预防性 Prevention focus 避免浪费 Avoids waste 提供质量一致的产品 Delivers consistent products 减少变量 Reduces variation 主动性 Proactive,于流程终点作检查 Inspect Product at the End of the Process 检查 Inspection 侦察性 Detection focus 容忍浪费

6、 Tolerates waste 返工 Reworks products 容忍变异 Tolerates variation 被动性 Reactive,SPC for Operators - Version 2.1 Mar. 10, 2001,23,数据的种类Types of Data,计量的 Variables 可用连续性的单位 Measure on a continuous scale 可以是流程或量度的特性 For a process or product 例子: Examples: 线宽 line width 板料厚度 lamination thickness,计数的 Attribute

7、s 数量,等级,类别 Count, grade, categorize 不能量度的 Cant measure it 一般是产品特性 Usually for a product 例子: Examples: 坏品百分比 % defective parts 甩货百分比 % orders late,SPC for Operators - Version 2.1 Mar. 10, 2001,24,控制图种类Types of Control Charts,计量控制图 Variables Charts 用于连续单位的量度 For data we get by measuring on a continuou

8、s scale. 例子 Examples 温度 temperature 线宽 circuit width 厚度 pin height,分别监察两组统计数值的三对控制图 Three pairs of charts that monitor two statistics.,平均及范围(X-R),Average & R (average and range),平均及标准差(X-S),Average & S (average and standard deviation),个别值移动范围(X-MR),X & MR (individuals and moving range),SPC for Opera

9、tors - Version 2.1 Mar. 10, 2001,25,计数控制图 Attribute Charts 用于数量等级或分类的数据 For data we get by counting, grading or categorizing things. 例子 Examples 甩货百分比 # of late deliveries 坏板百分比 # of defective circuit boards,计数控制图,Attribute Charts,NP,P,U,C,控制图种类Types of Control Charts,SPC for Operators - Version 2.1

10、 Mar. 10, 2001,26,规格Specifications,客户,供应商或内部工程要求 Customer, supplier or internal engineering requirements 包括: Include: 目标或中间值(最理想的) target or nominal value (the ideal!) 在目标值两旁可接受的变异 allowable variation on either side of the target value 规格上限=目标值+可接爱的变异 USL = target + allowable variation 规格下限=目标值-可接受的

11、变异 LSL = target - allowable variation,SPC for Operators - Version 2.1 Mar. 10, 2001,27,例子-酸浓度Example - Acid Concentration,规格是130克/升+/-30克升 Specification is 130 grams/liter +/- 30 grams/liter 规格上限=目标值+可接受的变量 USL = target + allowable variation 130 + 30 = 160 规格下限=目标值-可接受的变异 LSL = target - allowable va

12、riation 130 - 30 = 100 可接受变异的总值=规格上限=规格下限 Total allowable variation = USL - LSL 160 - 100 = 60,SPC for Operators - Version 2.1 Mar. 10, 2001,28,控制限-控制上,下限Control Limits - UCL, LCL,若流程受到控制: If your process is in control: 99.7%的数据将会在控制上限及下限之间. 99.7 % of the data points will be between the UCL and LCL.

13、 数据没有特定的图样=随机的. Data points will show no pattern = random. 大部分数据会趋向平均值. Most data points will be close to the average. 数据应有一半在平均值以上及一半在以下. Data points be 50/50 above and below average.,SPC for Operators - Version 2.1 Mar. 10, 2001,29,控制限-好处Control Limits - Benefits,减少两个可能的错误 Minimizes two possible m

14、istakes: 忽略问题 Ignoring a problem. 采取不必要的纠正行动 Taking unnecessary corrective action. 曲线下的出现可能性已知 Probabilities under the curve are known. 有利于预测和计划 Good for prediction and planning. 有利于侦察不正常的数据 Good for spotting weird patterns of points.,SPC for Operators - Version 2.1 Mar. 10, 2001,30,控制图及标准差Control C

15、harts & Standard Deviation,使用标准差决定控制上限及下限,如钟状曲线. To determine UCL & LCL, use standard deviation (s) - just like the bell curve!,利用变异的数值(标准差)去建立变异的一般范围 (控制上限及下限之间的范围)是否合理? Doesnt it make sense to use a measure of variation (standard deviation) to establish a normal range of variation (area between UC

16、L and LCL) for a process?,SPC for Operators - Version 2.1 Mar. 10, 2001,31,设定控制限Setting Control Limits,将钟状曲线转90度 Flip the bell curve on its side.,SPC for Operators - Version 2.1 Mar. 10, 2001,32,设定控制限Setting Control Limits,这是什么意思? What does it all mean?,SPC for Operators - Version 2.1 Mar. 10, 2001,

17、33,生产中使用SPCUsing SPC During Production,SPC for Operators - Version 2.1 Mar. 10, 2001,34,使用SPC-例子Using SPC - An Example,SPC for Operators - Version 2.1 Mar. 10, 2001,35,基本控制图格式Basic Control Chart Format,一般原因导致的变异 Common cause variation,特别原因导致的变异 Special cause variation,8,8.1,8.2,8.3,8.4,8.5,8.6,8.7,8

18、.8,8.9,9,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,mils,UCL,LCL,Y轴-量度 y-axis - scale for measurements,X轴-时间 X-axis - time sequence,SPC for Operators - Version 2.1 Mar. 10, 2001,36,平均值(典形数值) Average (the typical value) 平均年龄=(27+ 27+33+46+57) 5 = 38 岁 Average age = (27+27+33+46+57) 5 = 38 years,Average age

19、= 38,统计技术-中间值倾向Statistics - Central Tendency,SPC for Operators - Version 2.1 Mar. 10, 2001,37,统计技术-分布Statistics - Spread,范围(R)-最大数字减最小数字 Range (R) - highest number minus lowest number R= (57 - 27) = 30 岁 R = (57 - 27) = 30 years,幅度=30岁 Range = 30 years,27,27,33,46,57,SPC for Operators - Version 2.1

20、Mar. 10, 2001,38,统计技术-分布Statistics - Spread,SPC for Operators - Version 2.1 Mar. 10, 2001,39,例子-计数控制图Example - Attribute Chart,P Chart - VAAS Fastech Final Inspection,SPC for Operators - Version 2.1 Mar. 10, 2001,40,流程稳定性Process Stability,稳定的流程 Stable Process 一致的 Consistent 可预测的 Predictable 特别原因 No

21、special causes 受控的 In control 稳定性可用控制图量度 Stability is measured using control charts.,流程可以是受控,但不符合规格的. A process could be in control, but not meet specifications.,SPC for Operators - Version 2.1 Mar. 10, 2001,41,什么是流程?What is a process?,完成一件工作的一连串步骤 A series of steps we follow to accomplish a task.,S

22、PC for Operators - Version 2.1 Mar. 10, 2001,42,流程的内容The parts of a Process,SPC for Operators - Version 2.1 Mar. 10, 2001,43,稳定,能力及质量Stability, Capability & Quality,为能做到优越的表现,工作流程必须: To achieve performance excellence, work processes must be:,稳定,Stable,一致的,可预计的,consistent, predictable,有能力,Capable,持续符

23、合规格,continually meets specifications,持续改善,Continually improved,SPC for Operators - Version 2.1 Mar. 10, 2001,44,流程稳定及能力Process Stability & Capability,有能力的流程 Capable Process 流程有能力持续的满足规格要求 Process has the ability to continually meet specifications.,流程必须处于受控状态(统计技术角度),才可被认为有能力 Process must be in stati

24、stical control before it can be considered capable.,SPC for Operators - Version 2.1 Mar. 10, 2001,45,稳定Stability,SPC for Operators - Version 2.1 Mar. 10, 2001,46,变异Variation,个别成品之间不可避免的分别 The inevitable differences among individual outputs of a process.,一般原因导致的变异,Common Cause Variation,正常,常见,可预计的-自然

25、的,normal, usual, expected things - natural,特别原因导致的变异,Special Cause Variation,偶发性,不可预计的-特定的,sporadic, unexpected things - assignable,SPC for Operators - Version 2.1 Mar. 10, 2001,47,变异何时何地都会出现Variation is Everywhere!,SPC for Operators - Version 2.1 Mar. 10, 2001,48,变异结果Consequences of Variation,SPC f

26、or Operators - Version 2.1 Mar. 10, 2001,49,Cp及Cpk值Value of Cp and Cpk,根据规格评估流程表现.,Evaluate process performance against specs.,决定流程是否能满足新规格要求.,Determine if process can meet new specs.,根据Cpk及Cp值的距离制订改善目标.,Set improvement goal based on distance between Cpk and Cp.,评估供应商.,Evaluate suppliers.,用于销售过程的一部分

27、.,Use as part of sales process.,SPC for Operators - Version 2.1 Mar. 10, 2001,50,Cpk -量度流程设定Cpk - Measures Process Setting,比较流程中间值设定及目标. Compares setting of process center (average) to target. 基本定律: Cpk要求最少1.33 General rule - aim for Cpk of 1.33 minimum,SPC for Operators - Version 2.1 Mar. 10, 2001,

28、51,Cpk -例子Cpk Examples,SPC for Operators - Version 2.1 Mar. 10, 2001,52,Cp-量度流程分布Cp - Measures Process Spread,比较可接受变异(A)及实际变异(B) Compare allowable variation (B) to actual variation (A). B = USL - LSL A=6标准差 A = 6 standard deviations Cp = B/A,SPC for Operators - Version 2.1 Mar. 10, 2001,53,Cp 必须大于1C

29、p Should Be Greater Than 1,SPC for Operators - Version 2.1 Mar. 10, 2001,54,Cp -总结Cp - Conclusions,SPC for Operators - Version 2.1 Mar. 10, 2001,55,流程能力不足的两种情况Two Ways a Process Is NOT Capable,1.实际流程变异超出可接受变异的总值 Actual process variation (A - six sigma) exceeds total allowable variation (B - spec),Ta

30、rget,A,LSL,USL,SPC for Operators - Version 2.1 Mar. 10, 2001,56,流程能力不足的两种情况Two Ways a Process Is NOT Capable,2.如流程表现不足处于规格的中间位置,并其中一边的 控制限超越规格限. If process is not centered properly and one of the control limits exceeds the spec limit.,SPC for Operators - Version 2.1 Mar. 10, 2001,57,若流程能力不足如何办?What

31、if a process isnt capable?,流程需要改善,The process needs improvement!,首先,采取改善行动,减少变异,然后,按目标值将流程表现调至中间值.,First, take action to reduce the variation. Then, center the process over the target.,SPC for Operators - Version 2.1 Mar. 10, 2001,58,你需要做什么?What should you do?,SPC for Operators - Version 2.1 Mar. 10

32、, 2001,59,你需要做什么?What should you do?,SPC for Operators - Version 2.1 Mar. 10, 2001,60,你需要做什么?What should you do?,SPC for Operators - Version 2.1 Mar. 10, 2001,61,失控图样-第一定律Out-of Control Patterns - Rule 1,任何点超越控制限 Any point beyond the control limits,控制上限以外 Outside the Upper Control Limit,8.0,8.1,8.2,

33、8.3,8.4,8.5,8.6,8.7,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,LCL,Average,UCL,控制下限以外 Outside the Lower Control Limit,8.0,8.1,8.2,8.3,8.4,8.5,8.6,8.7,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,LCL,Average,UCL,SPC for Operators - Version 2.1 Mar. 10, 2001,62,失控图样-第二定律Out-of Control Patterns - Rule 2,连续七点向上或向下-走势 U

34、pward or downward run of 7 consecutive points -trend,连续七点向下 Downward run of seven consecutive points,连续七点向上 Upward run of seven consecutive points,8.0,8.1,8.2,8.3,8.4,8.5,8.6,8.7,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,LCL,Average,UCL,8.0,8.1,8.2,8.3,8.4,8.5,8.6,8.7,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,L

35、CL,Average,UCL,SPC for Operators - Version 2.1 Mar. 10, 2001,63,失控图样-第三定律Out-of Control Patterns - Rule 3,连续七点在平均值以上或以下-偏移 A run of seven consecutive points above the average or below the average - shift,连续七点在平均值以上 Run of seven consecutive points above the average,8.0,8.1,8.2,8.3,8.4,8.5,8.6,8.7,1,2

36、,3,4,5,6,7,8,9,10,11,12,13,14,15,LCL,UCL,连续七点在平均值以下 Run of seven consecutive points below the average,8.0,8.1,8.2,8.3,8.4,8.5,8.6,8.7,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,LCL,Average,UCL,Average,SPC for Operators - Version 2.1 Mar. 10, 2001,64,失控图样其它定律Out-of Control Patterns - Rule others,One point more than 3 sigmas from center line Nine points in a row on same side of center line Six points in a row , increasing or all decreasing Fourteen points in a row , alternating up and down Two out of three points more than 2 sigmas fro