Comparison and Application of Process Capability indices

공정능력지수에 대한 비교와 적용

  • Chung, Young-Bae (Dept. of Industrial and Management Engineering, University of Incheon) ;
  • Kim, Yon-Soo (Dept. of Industrial and Management Engineering, University of Incheon)
  • 정영배 (인천대학교 산업경영공학과) ;
  • 김연수 (인천대학교 산업경영공학과)
  • Published : 2007.12.31


Process Capability indices(PCIs) have been widely used in manufacturing industries to provide a quantitative measure of process performance. PCIs have been developed to represent process capability more exactly. The traditional process capability indices Cp, Cpk, Cpm, $Cpm^+$ have been used to characterize process performance on the basis of univariate quality characteristics. Cp, Cpk consider the process variation, Cpm considers both the process variation and the process deviation from target and $Cpm^+$ considers economic loss for the process deviation from target In the previous studies, only one designated location on each part is measured. System process capability index even though in single process, multiple measurement locations on each part are required to calculate the reliable process capability. In manufacturing industry, there is growing interest in quantitative measures of process variation under multivariate quality characteristics. The multivariate process capability index incorporates both the process variation and the process deviation from target or considers expected loss caused by the process deviation from target. In this paper, we compare various process capability indices and propose the application method of PCIs.


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