关键词: 充填平衡, 可视化, 注射成型

Abstract: Filling balance of injection molding is one of the main factors that influence the precision of plastic products. During the injection molding process, when polymer melt is filling the mold cavity, the flow forefront may shift left and right, thus causing filling imbalance. In order to make clear the mechanism of filling imbalance, one set of movable temperature measuring system equipped with infrared fiber sensor is designed. This system and visualization method are adopted to observe and analyze the aforesaid shifting phenomenon. The experimental results show that the shifting phenomenon and shifting degree of flow forefront at different filling speed are also different. The shifting of flow forefront is related to the flow behavior of melt in the runner and the variation of temperature field . A model of flow behavior of melt in the runner is constructed according to the experimental results and shear heat theory. The model can well describe the formation mechanism of the filling imbalance phenomenon. Tracer experiment of melt flow in the runner shows that the model coincides well with the actual situation.

Key words: Filling balance, Injection molding, Visualization