Research On The Numerical Simulation And Optimal Design Of Die For The Injection Moulding Of The Plastics With Thin-Wall

Injection molding for thin-wall is a new technology which developed on the basis of the traditional injection molding technology. Traditional injection molding process conditions has not met the requirements of the forming of the thin-wall plastic injection parts,because the polymer melts in the cavity with a high cooling rate. The polymer will cure in a short time, which makes the forming process complex and difficult, so it will directly affects the quality of plastic parts.For thin-wall plastic parts, warpage is the major defect in the injection molding process. Improving and reducing the warpage of the products, as well as optimizing the injection molding process parameters and mold structure has become the key factor in manufacturing of the plastic products, so it has attracted the product designer's attention.Based on the cooperation projection of "DC Brushless Fan of bus air conditioning system" by Chongqing Tonada Co., Ltd and Chongqing University of Technology,we mainly treat the warpage of the fan base as the study subject. We researched on the main process parameters by CAE which influenced the warpage of the products. Through Taguehi experiments, we obtained the best process parameters. Based on the the best process parameters, we obtained the warpage amount. Finally,we found that warpage is improved a lot ,but it was still exist and affected the accuracy of product assembly. In order to meet with the company requirements, we obtained deformation compensation amount by CAE again. The anti-deformed was applied to design mold in the parts of injection. We modified the three-dimensional model of the plastic part according to the deformation compensation amount. The mold was modified to offset the warpage according to the final compensation.Experiment was made on the injection device by rational design. Based on the theory of warpage, we analyzed the results of experiment .Several plastic parts will be selected randomly and measued. The results showed that warpage deformation is in the controllable range.It showed that deformation compensation was an effect way to design mold. Combining the CAE analysis with mold design of deformation compensation method ,the warpage is greatly reduced,the assembly precision of products are greatly increased,the production cycle is shortened, and the quality of the product is improved.