计量型数据MSA

Variable
N
Mean Median StDev
Delta
10
-0.410 -0.400
0.387
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
019 MSA-10
Effective Date: 2/2004
LSL
USL
产品公差 Product Tolerance
观察到的流程变差
Observed Process Variation
P/T = 10%
%R&R = 20%
P/T = 20%
%R&R = 40%
P/T = 50%
%R&R = 100%
This standard deviation is called the Standard Error f还是再现性？
Which does this primarily represent, Repeatability or Reproducibility?
019 MSA-11
Effective Date: 2/2004
GR&R 矩阵
GR&R Metrics
P/T
Ratio
%R&R
Red
Yellow
30%
30%
主要问题 – 我的测量系统是否适用于我的项目
Main Question - Is my measurement system okay to use on my project?
%R&R = 50%
P/T = 200%
%R&R = 100%
测量系统变差 measurement system variation
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
019 MSA-2
Effective Date: 2/2004
简单测量分析－ 续
Simple Measurement Study - continued
Variable Delta
N 10
Mean Median StDev -0.410 -0.400 0.387
• 使用上面的标准差，什么是测量分布的良好估计值
LSL
USL
产品公差Product Tolerance
观察到的流程变差 Observed Process Variation
P/T = 20%
%R&R = 20%
P/T = 50%
%R&R = 50%
P/T = 100%
%R&R = 100%
测量系统变差
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
Addresses what percent of the total variation is taken up by measurement error
• 同时包含了重复性和再现性

Includes both repeatability and reproducibility Operator x Unit x Trial experiment
简单测量分析－ 续
Simple Measurement Study - continued
• 使用描述性统计， 计算Delta 的标准差
Using Descriptive Statistics, calculate the standard deviation of Delta
• 这个标准差被称为测量标准误差
操作者 x 单位x 试验次数
• 最佳情况 Best case: 10% ； 可以接受 Acceptable: 30%
注意：6.0标准差代表了99.73% 的测量系统变差。记住在做测量系统和以前分析结果的计算
时，要经常检查这个值。 这里用的6.0 是AIAG 的工业标准。
Note: 6.0 standard deviations accounts for 99.73% of MS variation. Always check the value used when making comparisons between measurement systems or previous analysis calculations. The use of 6.0 is the AIAG industry standard. Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission.
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
019 MSA-6
Effective Date: 2/2004
测量能力指数－ % GR&R
Measurement Capability Index - % GR&R
% R& R

MS T o ta l
100
通常以百分比表示 Usually expressed as percent
• 描述有多少总变差比率是由测量系统误差造成的
计量性数据MSA
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
019 MSA-1
Effective Date: 2/2004
019 MSA-3
Effective Date: 2/2004
简单测量分析－ 续
Simple Measurement Study - continued
Variable Delta
N 10
Mean Median StDev -0.410 -0.400 0.387
这个比率被称为精确度和公差比率 (P/T). 这个例子中P/T 比率是：
测量系统变差 measurement system variation
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
This is interpreted as: “46% of the specification tolerance is taken up by measurement error”
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.
019 MSA-7
Effective Date: 2/2004
％重复性和再现性
% Repeatability & Reproducibility
Observed Process Variation
%R&R = 20%
测量系统变差
measurement system variation
%R&R = 75%
Copyright 2004 Cummins, Inc. All Rights Reserved.
019 MSA-5
Effective Date: 2/2004
精确度和公差比率
Precision to Tolerance Ratio
LSL
Product Tolerance
USL
P/T = 20%
测量系统变差
Using the standard deviation above, what would be a good estimate of measurement spread?
Precision Precision Precision
= 6 * = 6 * 0.387 = 2.32
• 假设公差是5 （上限－下限）
measurement system variation
019 MSA-9
Effective Date: 2/2004
LSL
USL
产品公差 Product Tolerance
观察到的流程变差 Observed Process Variation
P/T = 50%
%R&R = 25%
P/T = 100%
操作者 x 单位x 试验次数
• 作为一个目标，我们期望%R&R < 30%
As a target, look for %R&R < 30%
Copyright 2000-2002 Sigma Breakthrough Technologies, Inc. Used with permission. Copyright 2004 Cummins, Inc. All Rights Reserved.