A study of gate location optimization of plastic injection molding using sequential linear programming

A gate location is one of the most important design variables controlling the product quality of injection molding. In this paper, the numerical simulation of injection mold filling process is combined with the design optimization method to find the optimum gate location to achieve balanced flow. The objective function is expressed in terms of the difference between the maximum and minimum times of boundary filling. The coordinates of gate are chosen as design variables, and a constraint is employed to limit the clamp force lower than the reference value. The optimization problem is solved with the sequential linear programming algorithm, and design sensitivities are evaluated via the finite difference approximation. Finally, numerical examples are given to demonstrate the effect of proposed methods.