A control chart design for supplier in view of quality, due time and cost

This paper presents a design of the x control chart in view of quality, due time and cost to improve customer satisfaction of supplier. Recently, due to ever increasing competition in supplier markets, it is demanded to offer the low-cost and high quality product in short due time. Therefore, studying the balance of quality and the due time and cost has become a new problem to supplier. In short run process, the time of treating an assignable cause (ACT time) is an important effect to the total cost and due time. To resolve the above problem, in this research, first a design of the x control chart is developed in which the ACT time was considered. Then, from an economic viewpoint, the mathematical formulations which correspond to the design are shown. Finally, by numerically consideration, the balance of quality (control limits width) and due time and the total expectation cost is discussed, and the new relations between the due time ACT time and the total expectation cost are found.