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The Effect of Non-Return Nalve on Micro Injection Molding Machine

The micro injection molding machine (MIMM) is used to produce precision plastic products. The non-return valve (NRV) on the screw head of injection machine plays the role of preventing the melt back discharge during injection process. The sensitivity of non-return valves opening and closing affects the quality of the product. In this paper, numerical simulation of three-dimensional flow field is generalized by the Newtonian isothermal fluid method. Then, five kinds of different structural parameters of NRV are designed, and the pressure field, the pressure difference is simulated by the Polyflow software. At last, the pressure field, and the pressure difference on both side of NRV are analyzed and compared. The best structure parameter of NRV is decided. The simulation results are useful for the NRV design.