Trends & Practices of Process Capability Studies in Theory & Practice

From the end of 20th century, the use of Process Capability Indices (PCIs) to assess the process acceptability has become popular and widespread. The use of PCIs, which are the subject matter of this book have led almost inadvertently to substantial improvements in quality, but at the same time have been occasionally the cause of many unjust decisions, which could been avoided by better knowledge of their properties. Over the last 30 years, a number of measures have been devised to compare the requirements of specification with the capability of the manufacturing process. These measures take the form of indices constructed to take the value 1 for a properly defined balance between process capability and specification limits. These PCIs are unit less and directly related to the customer's specification. In this sense, they provide a common means of communication, independent of the technical details of the production. This book provides a detailed discussion of various types PCIs in case of uni-variate and multi-variate quality characteristics and clear understanding of the distinction between the various types of limits used in quality control applications.