EFFECT OF RUNNER SHAPE ON MELT FLOW CHARACTERISTICS IN INJECTION MOLDING

Abstract

Plastics play an important role as one of the key components of modern industry. The diversity and affordability of plastic materials enable them to find a wide range of uses in industry. The plastics industry has a wide range of products used in various fields such as automotive, packaging, electronics, medical and construction industries. There are many methods used in the production of plastic parts; injection molding, extrusion, blow molding, rotational molding and rotational molding, pressing and thermoforming. The most widely used of these methods is injection molding. Injection molding, one of the plastic injection methods, enables raw materials to be transformed into the desired shape with various production techniques. This method, which enables the production of plastic parts in a single process, accelerates product development processes by providing rapid prototyping for parts with complex geometries. At the same time, the use of recyclable materials that support environmental sustainability in industrial applications contributes to the environmental friendliness of the process. In this study, parts with four different runner geometries (diameter, quadrilateral, rectangular and hexagonal) to be produced by plastic injection molding method were designed with the help of CAD (Computer Aided Design) program. The runner geometry optimization of the designed parts was simulated with the help of CAE (Computer Aided Engineering) program and the changes in the runner pressure, filling time, melt pre-times and injection volume values were analyzed. The results of the analysis were compared with the mathematical results of the runner efficiency calculations in the literature. In both analyses, it was concluded that the optimum process conditions were obtained in the runner with rectangular geometry. This research provides important information on increasing the efficiency of the plastic injection molding process depending on the runner design