A Preliminary Study on Optimizing Injection Moulding Process by Using Response Surface Method

Abstract

In the injection moulding, the process parameters setting have crucial effects on the quality of products. Obtaining optimal conditions is necessary because the present day competitive conditions force injection moulding manufacturers to produce faster and cheaper product with a higher quality. In addition, unsuitable process parameter settings can cause many production problems as many product defects, long lead times and high costs. In the actual operations, the moulding process conditions are often selected from references or handbooks, and then adjusted subsequently by a trial-and-error approach. The process operators adjust one factor at a time until optimum conditions are obtained. However, this method is difficult to achieve due to the large number of factors being involved and the time-limited restriction. Moreover, this classical strategy for the selection of the optimum conditions is not appropriate when interactions between the different variables, affecting the response of the system, occur. This may lead to a false parameter setting.In this case, it would be desirable to apply optimization procedures that allow simultaneous variation of the different parameters affecting the response of the system. This approach is very costly and time consuming, as well as highly dependent on the experience of the moulding operators. There is an easy technique or method where injection moulders can use it to not only remain competitive, but also increase their profit. The method is “Response Surface Method”. RSM is a collection of statistical and mathematical techniques useful for developing, improving, and optimizing processes in which a response of interest is influenced by several variables and the objective is to optimize this response. RSM has important application in the design, development and formulation of new products, as well as in the improvement of existing product design. This study focuses on application of the methodology on how to optimize the moulding process parameters.