A multiprocess performance analysis chart based on the incapability index C-pp: an application to the chip resistors

Abstract

Statistical process control charts, such as the (X) over bar, R, S-2, S, and MR charts, have been widely used in the manufacturing industry for controlling/monitoring process performance, which are essential tools for any quality improvement activities. Those charts are easy to understand, which effectively communicate critical process information without using words and formula. In this paper, we introduce a new control chart, called the C-pp multiple process performance analysis chart (MPPAC), using the incapability index C-pp. The C-pp MPPAC displays multiple processes with the departure, and process variability relative to the specification tolerances, on one single chart. We demonstrate the use of the C-pp MPPAC by presenting a case study on some resistor component manufacturing processes, to evaluate the factory performance. (C) 2002 Elsevier Science Ltd. All rights reserved.