Sampling Plans Using Process Capability Index (PCI)

Abstract

The Process Capability Index (PCI) has been widely used in the industry to manage the quality of product. It has become an important tool of Statistical Process Control (SPC) for the continuous improvement of the quality. The PCIs are used to make a relationship between process quality and specifications limits and take into consideration both magnitude of process variance and process departure from the average. The PCIs are very useful to specify the number of non-conforming per million. The traditional sampling plans as mentioned in above chapters do not consider specifications limits to make final decision about the submitted lot of product. So, these plans can be used when the aim is to monitoring or inspection of lot through PCIs. Incorporating PCIs in the sampling plan makes it more attractive for the lot inspection where upper and lower specifications are given by the customer or producer or both. Thus, the aim of this chapter is to introduce some sampling plans using PCIs and application in the industry. So, in this chapter, we will focus on some latest sampling schemes using PCIs such as Repetitive Sampling using PCI, Resubmitted sampling using PCIs and some mixed plans using PCIs.