Injection molding is a popular manufacturing method for plastic parts. This technology is efficient for high-volume production, maintaining repeatability and cost-effectiveness. However, any deviation in tooling,  process variables, and raw material quality causes various defects in molded parts. A flow mark in injection molding is one major defect that influences the finish and aesthetic appeal.

Understanding the nature of flow marks can help you produce defect-free parts exact to your design specifications. So, let’s discuss types of flow marks, their causes, and prevention strategies in detail.