Application of Taguchi Design Approach in the Optimization of Die Design Parameters of a Two Cavity Injection Molding Tool for a Fan Blade Back Cover

Injection molding methods are widely used in plastic industries for the production of intricate and complex shapes of plastic, FRP parts with higher dimensional accuracy and greater reliability. In the present work an attempt has been made to improve the quality characteristic such as shrinkage of a two cavity injection molding tool for a fan blade back cover made from polypropylene (PP) by optimizing the die design parameters of injection molding tool using the Taguchi design approach. The performance of Fan Blade Back Cover is evaluated in terms of its shrinkage behavior by using the above measured data, Taguchi technique has been employed in optimization of various parameters, which controls the shrinkage, like injection and holding pressure, injection speed, melting temperature, cooling and holding time, with their significance in respect of shrinkage using orthogonal array, S/N ratio and ANOVA with their confirmation tests. Optimal combination of parameters is found out. A good agreement has been found between the estimated and experimental results within the preferred significant level. The optimum combination was verified experimentally and it was confirmed that Taguchi method successfully improved the quality of injection molding of polypropylene material as per customer's specifications.