An efficient integrated approach to reduce scraps of industrial manufacturing processes: a case study from gauge measurement tool production firm

In the last decades, continuous improvement in industrial manufacturing processes is one of the fundamental principles for remaining in the competitive trade environment. This subject has a particular importance in production process of gauge measurement tools because of their high price. The main objective of this study is to reduce the scraps of gauge measurement tool manufacturing process with implementing of an efficient integrated approach based on six sigma methodology, failure mode and effects analysis (FMEA) technique, design of experiment (DOE) technique, and also simultaneous analysis of several response variables by two different methods. At first, critical to quality (CTQ) factors are determined to specify the quality level of manufacturing process. Then, different causes of poor quality in gauge measurement tool manufacturing process are determined and displayed as a cause and effect diagram. The main causes of poor quality of manufacturing process are determined by using the FMEA technique. After that, adopted for more accurate considering, the DOE technique is employed for analyzing of several input parameters of the manufacturing process and determining of optimal values of them. As a further step, a simultaneous analysis and optimization has been done by two different methods, first, optimization tool of Design-Expert software, and second, the goal programming (GP) from multi-criteria decision making (MCDM) topics. Based on the obtained structure, an optimal set of parameters and levels are determined for the different manufacturing process parameters. The experimental results for a case study illustrate substantial improvements in producing process of gauge measurement tool.