Approach to improve the injection weight repeatability accuracy in the process of the precision injection molding

According to the mechanism of precision injection molding, the influence of the product quality in the precision injection molding and the settlements, this paper proposes the importance of the on-line measurement of polymer melt density to improve the weight repeatability accuracy of the precision injection work piece. It analyses the limitation that the control of injection volume is unable to effectively realize precision control of the injection weight in the traditional injection molding process and also the limitation of PVT process control to improve the injection weight accuracy in the injection process in principle. It also discusses the feasibility of the injection weight control based on the on-line measurement of polymer melt density to improve the work piece weight repeatability accuracy using the equivalence injection principle of the injection molding and investigates the weight control approach in the injection molding process.