Analysis of a x̅ chart design for quality management information system in short delivery time processes —From the activity of “control chart practical applications study group” of JSQC

This paper analyses a design of the xmacr control chart for quality management information system used in short delivery time processes. This work is from the activities of control chart practical applications study group of JSQC (The Japanese Society for Quality Control). In these days, because the demands of low price, high quality and short delivery time from the customer have become severer, studying the relations between the power of process and delivery time and cost have become an important problem to manager. To resolve this problem, in this research, first a design of the xmacr control chart is presented and its mathematical formulations are shown. Then, the presented design based on the judgment rules of JIS Z 9021 [1] is studied. Finally, by numerically consideration using the data from real situation, the relations of the power of process and delivery time and the total expectation cost are discussed.