Evaluating measurement and process capabilities using tabular algorithm procedure with three quality measures

Abstract

In a normal quality improvement activity, the measurement system analysis (MSA) is assessed prior to process capability analysis (PCA). The tabular algorithm is widely applied for MSA. This research extends the use of the tabular algorithm for concurrent MSA and PCA. In practice, several indices are used to judge the capability of the measurement system, including precision-to-tolerance ( PTR), percentage repeatability, and repeatability and reproducibly (% R& R), number of distinct categories ( NDC), whereas the most common index for assessing the capability of manufacturing process is the potential process capability index, C p. In order to assess the capabilities of a measurement system and manufacturing concurrently, these indices are combined into two proposed capabilities assessment procedures. The first procedure adopts the PTR, % R& R and C p, while the second procedure employs the PTR, NDC and C p. Three previously conducted case studies are utilized for illustration. The results showed that the tabular algorithm with either capabilities assessment procedure effectively judged the capabilities of the measurement system and manufacturing process, which may save considerable engineering efforts. In conclusion, the tabular algorithm combined with the proposed assessment procedures can provide valuable guidelines that can be easily understood and applied by practitioners in a wide range of industrial applications.