Integrated Process Capability Analysis

摘要

Process Capability Analysis (PCA) is a powerful tool to assess the ability of a process forrnmanufacturing product that meets specifications. The larger process capability index implies thernhigher process yield, and the larger process capability index also indicates the lower processrnexpected loss. Chen et al. [5] has applied indices C_(pu), C_(pl), and C_(pk) for evaluating the processrncapability for a multi-process product with smaller-the-better, larger-the-better, andrnnominal-the-best specifications respectively. However, C_(pk) cannot reasonably reflect the processrnexpected loss. In this paper, index Cp n is selected to replace Cpk. Indices C_(pu), C_(pl), and Cpn arernused to evaluate the entire process capability for a multi-process product with smaller-the-better,rnlarger-the-better, and nominal-the-best specifications respectively. An integrated processrncapability index for a multi-process product is proposed. The relationship between processrncapability index and the process yield is introduced. A multi-process capability analysis chartrn(MPCAC), reasonably revealing the status of process capability for the entire product, isrnconstructed for practical application. An evaluating procedure of the process capability for thernentire product is also provided.