工序能力指数的统计分析及改进

Statistical Analysis and Improvement of Process Capability Indices

为了提高制造过程质量,预防和减少不合格产品的数量,必须选用高效的控制方法对制造过程进行质量控制,针对当前工序能力指数C_P和C_(pk)应用不足,难以指导质量问题原因查找和改进方向的缺点,提出了适于现场应用的三个过程能力测度指标C_(pa),C_(pe)和C_(pc),用于反映和控制过程质量的分散和偏移,通过具体应用实例,证明了改进指标的适用性。

To increase product quality and predict the unqualified products, effective control methods must be selected. Considering the disadvantages of process capability indices Cp and Cpk that are hard to help to find the reason of quality problems and direct quality improvement, three new indices Cps, Cpc, and Cpc available in real time are introduced to control the scatters and errors. Finally the feasibility of these indices is proved by an application.