ABSTRACT
This chapter describes the construction of statistical process control charts designed to monitor measures of process capability. They are used after a process has been brought into a state of statistical control and once the process has been demonstrated to be capable of producing a quality product or service. Control charts are described for monitoring capability indices such as the proportion of nonconforming items, the rate of nonconformities, C p and C pk . Acceptance control charts are also described, which plot sample means on a control chart similar to an X-bar chart. However, the control limits are located at a specified distance from the specification limits, rather than with respect to the process mean. For high C pk processes, acceptance control charts allow the process mean to vary as long as it does not get too close to the specification limits.
