From time to time, I see requests by customers to control the process according to capability indices. Basically, what they want is for operator to be able to directly see Cp/Cpk in the O-QIS products.
Seems like a good idea, right? The operator measures the parts and can see if the Cp/Cpk turns red (not capable). Then they can do some adjustments to the process, start producing OK parts and be happy again, right?
Wrong.
Because Cp/Cpk still can be not capable after adjustments to the process. And the operator is not happy. He is confused now because he is measuring good parts but still see red colour for Cp/Cpk evaluation. What should he do?
Answer is, he should have not been put into this position in a first place. Cp/Cpk alarming in the shopfloor environment does not make much sense.
For detailed explanation please read this: https://nexus.hexagon.com/community/cfs-filesystemfile/__key/communityserver-wikis-components-files/00-00-00-01-82/FAQ_5F00_Why_2D00_Not_2D00_Cp_2D00_Cpk_2D00_In_2D00_O_2D00_QIS_5F00_EN.pdf?_=638413312506406191
