Impact of injection molding technology parameters on weld line defects
Published: July 27, 2026
Abstract
The injection molding process of plastic products is a complicated process with many potential defects, such as warpage, short shot, and burning. During the injection molding process, the weld line defect occurs when two plastic flows meet. This defect reduces the durability of plastic products. Many researchers are interested in the treatment of weld line defects. There are many parameters that affect the weld line, including the mold surface’s temperature, the plastic temperature, and the plastic flow velocity. These three parameters significantly impact the weld line’s size and angle. In this study, SolidWorks software was used to simulate the injection molding process and identify weld line defects. The simulation results show that the plastic flow velocity has the strongest impact, with a stable characteristic, on the injection molding process. Meanwhile, the mold surface’s temperature and the plastic temperature have lower impacts.
Keywords
injection moldweld lineinjection molding processsimulationsweld line defect
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