You are the process improvement manager and have developed a new machine to cut insoles for the company’s top-of-the-line running shoes. You are excited because the company’s goal is no more than 3.4 defects per million, and this machine may be the innovation you need. The insoles cannot be more than {.001 of an inch from the required thickness of .250. You want to know if you should replace the existing machine, which has a Cpk of 1.0.

Mean of the new process X = .250 inches.

Standard deviation of the new process = s = .0005 inches.

APPROACH c You decide to determine the Cpk, using Equation (S6-14), for the new machine and make a decision on that basis.