Abstract: L27(313) experiments were performed in order to determine an optimum condition for minimizing the volumetric shrinkage in multi-cavity injection molding part of polypropylene (PP). It showed that the mold temperature and packing time had the greatest influence on the volumetric shrinkage. Based on a standard analysis of variance(ANOVA), it was found that the relative significance of the factors on the volumetric shrinkage was in the descending order: packing time, mold temperature, melt temperature, and packing pressure. Using the optimized level of factors, the volumetric shrinkage was decreased by 21.46％.

Key words: multi-cavity injection molds, process optimum, volumetric shrinkage