Plastic injection molding is one of the widely used methods of forming plastic materials. The process of cooling the mold in injection molding has an important role in reducing the production costs and increasing the product quality. Thanks to the evolving additive manufacturing technologies, complex geometry cooling channels can be produced. In this study, the effect of the conformal cooling channels was investigated in order to increase the cooling efficiency of plastic injection molds. For the numerical analysis a plastic part with complex geometry was determined. For the cooling of the plastic injection mold, cooling channels with straight, spiral and zigzag form have been designed. In the channel design, the distances of the cooling channels to each other and to the mold cavity are controlled by a design algorithm. Numerical analysis was performed to examine the effect of the designed cooling channels. In the numerical analysis, the change in the cooling time and the temperature distribution on the plastic part were observed. The cooling time is shortened by the use of conformal cooling channels according to the cooling with the straight cooling channel. A more homogenous temperature distribution was obtained as a result of the analysis with the conformal cooling channels. It has been observed that the cooling process with the spiral cooling channel lasts for a shorter period than the cooling done with the zigzag cooling channel.

Keywords - Conformal cooling channels, Plastic injection molding, Plastic part warping, Cooling time, Additive manufacturing

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