Measurement techniques in injection molding: A comprehensive review of machine status detection, molten resin flow state characterization, and component quality adjustment

Injection molding is a widely favored method for accurately fabricating objects with intricate geometries. However, the machine, melt, and product fluctuate from shot to shot due to multiple devices and processes, and complex dimensions in mold, presenting numerous challenges in producing high-consistent products. Many state-of-the-art measurement technologies have been developed to overcome those limitations. The main objective of this review is to summarize the recent progress in measurement techniques in injection molding. The techniques primarily focus on machine status detection, melt flow state characterization, and component quality adjustment. Here, we systematically reviewed various strategies and underlying mechanisms used for measurement, including clamping force, demolding force, clamping mechanism, viscosity, process parameters, and pressure-volume-temperature characteristics. The key points on the new method's perspectives were identified in the end. Overall, this paper provides a valuable resource for researchers to promote high-consistent material processing, highlighting advancements and challenges in this rapidly evolving area.