Statistical Process Control Using Control Charts with Variable Parameters

An extremely important issue in quality management is monitoring and diagnosing processes, and, subsequently, supervising them using so-called control charts. In typical production charts with constant parameters are commonly used, such as x-R, x-s, CUSUM, EWMA others, which, most cases, effective tools for process stability evaluation. Charts considered untypical (in statistical control) those variable sample sizes, sampling intervals and/or limits. Such used when analysis based on standard, well-known may lead to serious errors. Modern a response the requirements of Industry 4.0 an excellent tool processes. Their use together Cp Cpk indices other capability starting point improvement. The methodology nonstandard inadequately recognized rarely practice. theory their design examples will be presented characterized this paper.