Study on the evaluation and compensating strategy for the wear damage of non‐return valve during injection molding process

Abstract

Injection molding (IM) is one of the most essential forming methods for plastics. However, some potential risks which influence part quality may occur in the molding process. A non-return valve (NRV) is a major component on the screw head whose function is to seal during the injection process to prevent the backflow of the melt. The NRV will wear in this process and cause fluctuations in parameters and quality but the wear states of NRVs cannot be monitored without the disassembly of the injection barrel. In this study, we proposed an optimization method to compensate for the wear damage of the NRVs. The V/P switchover point in each molding cycle was recalculated and output to stabilize the part quality. As a result, the wear damage of the NRV on the current machine was able to be predicted and the part quality could be initially optimized in the condition that the NRV had a degree of wear. The experimental results reveal that our proposed compensation algorithm can monitor the type of wear of NRV online, and at the same time, it can compensate the axial wear of NRV and finally improve the consistency of product weight, which established a fundamental for further research in the future.

Intelligent recommendation system of the injection molding process parameters based on CAE simulation, process window, and machine learning

“…Utilizing computer simulation-aided technology, product design optimization and quality assessment can be achieved. Nevertheless, simulation results may significantly differ from the actual molding process due to variations in resin and machine response, as well as deviations in operating conditions [7] . Hence, it is challenging to rely entirely on CAE simulation to recommend optimal injection molding process parameters.…”