Citation :

Wan Noor Azrina Wan Azhari, Mohd Amran Md Ali, Subramoniam Sivarao, Mohd Najib Ali Mokhtar, "Optimization of Injection Moulding Parameters for Reducing the Shrinkage Using the Taguchi Method," International Journal of Engineering Trends and Technology (IJETT), vol. 73, no. 12, pp. 266-271, 2025. Crossref, https://doi.org/10.14445/22315381/IJETT-V73I12P121

Abstract

The injection moulding input factors were optimized employing High-Density Polyethylene (HDPE) plastic material in a two-plate family injection mould. It is well known that non-optimal parameters lead to increased rework time to remove flashing, excessive raw material waste, poor product quality, and higher production costs. Therefore, establishing appropriate injection moulding settings was not easy to ensure minimizing production time, material waste, and cost. This study aims to use statistical methods to optimize the injection moulding input factors to reduce shrinkage. The experimental work was conducted using the Design of Experiments (DOE) approach based on the Taguchi method. The parameters selected were the size of shot, pressure of injection, speed of injection, and force of clamping. Analysis of Variance (ANOVA) was applied to determine the significance of each input factor and to identify the optimal combination. The moulded samples were evaluated based on weight changes to determine the shrinkage percentage. The results show that the size of the shot is the most significant factor influencing shrinkage, followed by pressure of injection, speed of injection, and force of clamping. The optimization process achieved an improvement of 8.4% in shrinkage reduction, where the shrinkage decreased from 30.22% to 27.66%. Therefore, by applying the Taguchi optimization method, the reduction of shrinkage on the moulded parts can be improved, leading to enhanced product quality and manufacturing efficiency.

Keywords

Analysis of Variance (ANOVA), High-Density Polyethylene (HDPE), Injection Moulding Parameters, Shrinkage, Taguchi Method.

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