Process capability analysis for an entire product

Process capability indices (PCIs) are powerful means of studying the proces s ability for manufacturing a product that meets specifications. Several ca pability indices including C-p, C-pu, C-pl and C-pk have been widely used i n manufacturing industry to provide common quantitative measures on process potential and performance. The formulas for these indices are easily under stood and can be straightforwardly applied. However, those process capabili ty indices are inappropriate for asymmetric tolerances and could not be app lied to evaluate multiprocess products. Based on C-p, C-pu, C-pl and C-pk, this research aims to develop one process capability analysis chart (PCAC) for precisely measuring an entire product composed of symmetric tolerances, asymmetric tolerances, larger-the-better and smaller-the-better characteri stics. The process capability analysis chart evaluates the capabilities of multi-process products and provides chances for continuous improvement on t he manufacturing process.