How high should Cpk be? Why 1,3 - 1,67 is the sweet spot and 2 is too high.

There is a school of thought that suggest you should have a Cpk of 2.0 - that is, in fact, very much in line with Six Sigma: having 6 standard deviations of process variance between the process mean and a specification limit will yield a Cpk of 2. But I would argue that this is too high for most companies and industries.

In this video, we'll cover some rules of thumb for how high your Cmk, Cpk and Ppk should be; what the difference between those three is, to begin with; and how you can decide on a proper target for your organisation.

In short, I suggest a Ppk of more than 1.0, a Cpk of at least 1.33 and a Cmk of at least 1.67 - check out the whole video for the reasoning behind this.
#continuousimprovement #cpk #sixsigma
   • How high should Cpk be? Why 1,3 - 1,6...  

00:00 Understanding Cpk Basics
02:56 Process Performance vs. Process Capability
06:46 Buffer Capability for late Detection
07:36 Machine Capability (Cmk) Explained
11:08 Debating the 1.67 Rule
14:04 Why Not Aim Higher Than 1.67?
19:37 Conclusion and Resources