Rahebe Keshavarzi - MSc, Department of Industrial Engineering, Science and arts university, Yazd, Iran
Mohammad Hossein Abooie - Associate Professor, Department of Industrial Engineering, Yazd University, Yazd Iran

Process capability indices (PCIs) can be used as an effective tool for measuring product quality and process performance. In classic quality control, there are some limitations which prevent a deep and flexible analysis because of the crisp definition of PCA’s parameters. Fuzzy set theory can be used to add more flexibility to process capability analyses. In this study, the fuzzy and control charts are introduced to monitor continuous production process in triangular fuzzy state. Also, fuzzy PCIs are produced when SLs and measurements are triangular fuzzy numbers (TFN). For this aim, a computer program is coded in Matlab software. The fuzzy control charts are applied to Yazd fiber production plant. The results show that in continuous production processes, the better analysis will be performed by using fuzzy measurements. Also, based on the fuzzy process capability indices (FPCIs), we can have a flexible analysis of the process performance

Triangular fuzzy process capability indices, Specification limits, Continuous production process, Process capability analysi, Fuzzy set theory, Fuzzy measurements