Research of Multi-operation Quality Control based on Minimum Quality Loss

Aiming at the problem of mutual influence between multi-operation and the optimization of quality control in product manufacturing process, quality transfer model between the preceding operation and the succeeding operation is established based on two kinds of quality. Partial quality of the succeeding operation is analyzed quantitatively through analysis and calculation of this model, so that quality control in the succeeding operation is implemented without the preceding influence. And quality loss model of multi-operation is introduced using Duncan cost model and Taguchi quality loss function. The loss model takes into account quality loss of multi-operation in product manufacturing process from the point of view of overall optimization. Based on analysis of the model, grid-search approach is applied and minimum quality loss is calculated as optimization objective so that control chart is designed optimally. Then the sample size, the sampling interval between successive samples, and the control limit coefficients of the chart are determined for multi-operation quality control. Finally, the model is analyzed by an instance of coating operation in purifier manufacturing process, and the result shows that the model is effective on reducing the manufacturing cost and guaranteeing the product quality