ABSTRACT
This chapter discusses the selection of the key process measurements, the monitoring of the appropriate process information, and the use of this measurement data to improve process performance. Process variability hinders the efforts of system operators to control the quality and cost of manufacturing operations. Real-time process parameter measurements can provide the information needed to deal with unexpected excursions in manufacturing system output. In-process measurements offer the best alternative as long as the time required to collect the data is not an unacceptable cost to the production operations. Measurement processes that do not meet these criteria provide little, if any, value and only harm the relationship between the shop and the organization that has supported the alteration to the previous manufacturing process. In addition to improving the accuracy and consistency of manufacturing operations, in-process measurements of critical parameters can be used to provide real-time assurance that the workpiece quality is being maintained at the desired level.
