To calculate Cpk, several steps are needed. The first step is done, measuring the parts. The next step is to calculate the upper tolerance for each part. To do this, determine the bonus tolerance allowed for each part. 1. Calculate Bonus Tolerance.

2016年4月22日 · I am doing a capability study and a Gage R&R on a positional tolerance that has a maximum material condition (MMC) modifier. So with the MMC modifier, the tolerance is technically different for each sample, based on the amount …

Need a Cp Cpk True Position Template for Excel? QI Macros has a ready made true position template for you! What is True Position? If you are drilling a hole which has an X and Y location, you have to be able to measure Cp and Cpk for both the X and Y dimensions as well as the overall location of the hole:

CPK是指“过程能力指数”，我们在过程中收集数据进行分析时，经常会被客户问到 “这个过程有足够的能力来生产合格品？ 它有一个怎样的质量保证能力，制造过程是否稳定等？ -- 通过制程能力指数的研究来评估质量现状. --从过制程能力数值可反映出过程不合格PPM（一百万个零件多少不合格） --通过研究制程能力来发现质量的改进途径. 2 怎么计算CPK. 第一步：选用30-50的样本数，然后测量实际数据。 第二步：算出样本的平均值µ，计算方法如下。 µ = (X1 + ‥ +Xn) / n. 第三 …

Cpk计算 既然有了每个零件公差使用率的确定方式，我们就有了共同的上公差— 100%，及允许公差的100%。 为了让统计软件计算，要用小数形式来表达，和百分比效果相同。

2009年3月31日 · The Basic Formulas for Cpk, Ppk require Constant Value Limits. I recall this situation a number of times in Automotive Stamping and we simply set the LSL and USL to the Minimum Tolerance Values, without factoring in Bonus tolerances. This forced us to Control the process and not have any extra help from MMC.

2019年9月3日 · Does anyone have a good approach to including MMC bonuses on both feature and datum sizes into a Cp and Cpk calculation. This is a difficult question to answer as there are numerous methods with no consensus on which is best. One approach uses the average bonus tolerance. Another uses the residual tolerance (bonus tolerance - position).

Last month’s Tip showed how to inspect features of size where the geometric tolerance is modified at MMC or LMC without having to find the axis or center plane. The geometric tolerance in these cases is a single limit control. Once that is realized, it is easy to calculate a Cpk index on such geometric tolerances.

2018年10月19日 · Cpk计算 既然有了每个零件公差使用率的确定方式，我们就有了共同的上公差— 100%，及允许公差的100%。 为了让统计软件计算，要用小数形式来表达，和百分比效果相同。

2010年10月1日 · My recommendation would be to calculate the percentage of tolerance with bonus used on every reading and use the variance in percentages compared to 100% allowed as tolerance for calculating the Cpk. This method has some shortcomings but is the closest to what I would look for and the easiest to handle in the shop floor