This paper suggests a systematic approach to reduce defects in injection moulded components. The component taken for analysis was an injection molded gear made of Stanyl (Nylon 4, 6)-15% Carbon Filled, used in an automobile. The analysis applies Taguchi Methodology to investigate the effects of process conditions on the shrinkage and warpage characteristics of the product made from a two cavity injection mould. The effect of seven process parameters on the Shrinkage and Warpage of the component were analyzed. An L18 standard orthogonal array (seven parameters with three levels) was chosen. The samples selected at random from each experiment were measured for warpage and shrinkage. The data thus obtained were analyzed with quality control tools like ANOVA (Analysis of Variance) and Factor Plots. Based on the results from ANOVA, the parameters which have significant effect on the quality of the product were identified. The factor plots gave information regarding the optimum levels of parameters to be maintained . The optimum levels of the parameters were used for conducting confirmatory experiments, which gave products with shrinkage and warpage within acceptable limits.
Dr. Jayanarayanan K., Bhagawan, S. S., Karthick, H. S., Suganya, V., and Shivashankari, A. L., “Optimization of Process Parameters of an Injection Moulded Gear Using Taguchi Method”, Annual Technical Conference (ANTEC 2006) organized by Society of Plastics Engineers. Charlotte, North Carolina, USA, pp. 1088-1092, 2006.