MODEL BASED SIX SIGMA CONCEPT AND PROCESS CAPABILITY INDICES: THE RESEARCH STUDY OF OIL INDUSTRIAL CASE IN YEMEN

Process capability indices are utilized extensively in the quality control inspection process, both at the level of production and for general business operations. They take into consideration both the location and the deviation from the specified limits and targets. Several literatures have contained contributions on this issue. Existing PCIs based on Six Sigma, on the other hand, merely displayed a range of quality levels rather than a single quality level value. Thus, previous studies have found the insufficient and ineffective deployment of Six Sigma to process control and yield process. Motivated by industrial Aden oil refinery process performance case study, we discuss the density characteristic of oil to estimate the process yield, and the capacity of the process.In addition, an effort to identify the level of quality in which the refinery operates. By investigating two different methods for estimating process yield, the sigma level, which areby extends the indicesto estimate capacity, level of sigma, and yield process. The analyses and findings indicated that the indicesoutperformed the existing indices. Ultimately, Six Sigma-based process yield index represents a potential approach that other industries and practitioners can utilize to assess process performance and quality control.