Optimization method of production process and control parameters. Application to plastic injection molding process.

This paper presents an application of new statistical parameter optimization method to designing plastic injection molding process. Optimum condition is derived by combining highest level of SN ratio of each parameter. The SN ratio represents the variance of products and the process control ability in trial production on many parameter's conditions layouted orthogonal array. This optimization is carried out on two characteristics of products. Selection method of control parameters is discussed to reduce process fluctuation still remained after the parameter optimization. The effect of optimization and the possibility of control by the method are confirmed experimentally. The results show improvement in the process variance of more than 5 dB and possibility of both two-characteristics optimization and control.