In automobiles, lock parts are matched with inserts, and this is a crucial quality standard for the dimensional accuracy of the molding. This study employed moldflow analysis to explore the influence of various injection molding process parameters on the warpage deformation. Deformation of the plastic part is caused by the nonuniform product temperature distribution in the manufacturing process. Furthermore, improper parameter design leads to substantial warpage and deformation. The Taguchi robust design method and gray correlation analysis were used to optimize the process parameters. Multiobjective quality analysis was performed for achieving a uniform temperature distribution and reducing the warpage deformation to obtain the optimal injection molding process parameters. Subsequently, three water cooling system designs—original cooling, U-shaped cooling, and conformal cooling—were tested to modify the temperature distribution and reduce the warpage. Taguchi gray correlation analysis revealed that the main influencing parameter was the mold temperature followed by the holding pressure. Moreover, the results indicated that the conformal cooling system improved the average temperature distribution.

Locks may be inserted during the production of certain auto lock-parts. Warpage of auto lock-parts during injection molding is the most critical problem facing product quality. This warpage is mostly affected by the processing parameters and design of the injection mold. In this paper, the influences of molding conditions on the warpage of auto-lock parts were studied using a mold filling analysis software. This study combines the Taguchi method and grey relational analysis to find the optimal set parameters for auto lock-parts and to analyze the effect of individual parameter on the warpage and the temperature distribution results. We then configure different cooling design change temperature distribution and reduce warpage, respectively, the original cooling, U-shaped cooling and conformal cooling with each other. From the results, it is shown that the factor that the most strongly affects the warpage is the mold temperature, with packing pressure being a secondary consideration. The optimum parameters that can minimize the warpage defects filling time (0.6 s), melt temperature (260°C), mold temperature (65°C), injection pressure (125 MPa) and packing pressure (140 MPa).