Abstract
The objective of this paper consists in the minimization of warpage problems which depend on the process parameters during injection molding of thin wall plastic parts using an optimization technique involving Taguchi method, S/N ratio and ANOVA method. For this purpose, a number of experiments are carried out by utilizing the combination of process parameters based on a three-level L9 Taguchi orthogonal array table. To achieve the minimum warpage, the optimum level of process parameters is determined. A drain with 8 sockets is investigated, where melt temperature, mold temperature, injection speed, and packing pressure are selected to be the process variables. The results show that the optimum parameters that can minimize the warpage problem are: melt temperature (190°C), mold temperature (30°C), injection speed (70 mm/s), and packing pressure (55 MPa). The most effective factor on the warpage is packing pressure with a general influence of 55.71%. Keywords: plastic injection molding; thin wall parts; warpage; Taguchi method; S/N ratio; ANOVA method; optimization