Process Capability Studies in an Automated Flexible Assembly Process: A Case Study in an Automotive Industry

Document Type : Research Paper


1 Faculty of Industrial and Systems Engineering, Tarbiat Modares University, Tehran, Iran

2 Department of Industrial Management, Faculty of Management, University of Tehran, Iran

3 Department of Industrial Management, Faculty of Management and Economics, Tarbiat Modares University, Tehran, Iran


Statistical Process Control (SPC) methods can significantly increase organizational efficiency if appropriately used. The primary goal of process capability studies is to obtain critical information about processes to render them even more effective. This paper proposes a comprehensive framework for proper implementation of SPC studies, including the design of the sampling procedure and intervals as well as process capability indices. Some of the most essential process capability indices in the literature were reviewed to develop a methodology to utilize process capability indices within the SPC framework. The current study presents an efficiency-oriented criterion designed for measuring SPC implementation productivity. The framework is applied to the windshield installation process of an Iranian automobile assembly line. The process was sampled in various sessions. Results verify that the implemented SPC framework could successfully improve the process and that the proposed framework could significantly address bottleneck in the process and enhance the quality level of the process from satisfactory to excellent according to the reference values of process capability indices. Managerial insights are also drawn from results.


Main Subjects

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