As rapid advancement of the manufacturing technology, suppliers require their products be high quality with very low fraction of nonconformities. Traditional methods for measuring fraction of nonconformities become inapplicable for those high quality processes since any manufacturing sample of reasonable size likely contains no defective product items. In this paper, we first comment on the classical approach, then present an effective modern approach based on process capability indices for measuring manufacturing process quality, specifically for high technology product requiring very low fraction of nonconformities (often measured in PPM, parts per million). In addition, several implementation issues and extensions are discussed. The manufacturers can use the presented approach to perform quality testing and determine whether their processes are capable for reproducing product items satisfying customers' stringent quality requirements.
|Number of pages||15|
|Journal||Journal of the Chinese Institute of Industrial Engineers|
|State||Published - 1 Jan 2005|
- Critical values
- Fraction of nonconformities
- Lower confidence bound
- Process capability indices