Optimization of Nozzle Section in Plastic Injection Moulding Process

Abstract

In this study, the thermal analysis and numeric modelling of flow in nozzle of a real plastic injection machine with injection weight of 300 gram were conducted. The nozzle geometry was changed to optimize flow in nozzle for high-density polyethylene HDPE at temperature of 200 °C and injection pressure of 150 MPa. For numeric modelling, the ANSYS Fluent R14 was used. The analysis was made for four different geometries consisting of real system dimension r-NG and others design dimensions NG1, NG2 and NG3 . The results of the analysis showed that the most suitable flow was determined in the third NG3 design. In this geometry, for flow in the nozzle section, rounding was made in the sudden shrinking flow section to give a throat shape and so, the geometry ensuring optimized flow was obtained. As a result, with changing of nozzle geometries of plastic injection machines having different pushing capacities they were used in the industry, the positive results will be able to be obtained.

Keywords

• Plastic injection,HDPE,Nozzle,Finite volume method,Optimization

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