Analysis of Warpage on front panel housing using Response Surface Methodology

Abstract

In injection moulding process, moulded plastic parts is consider one of the most economical manufacturing process with high volume of plastic parts produces. Causes of variations in injection moulding are related to the vast number of factors acting during a regular production run, which directly impacts the quality of final products. Quality of moulded plastics parts is important as it increasing demands from industries, defects in plastic moulded parts such as warpage is common problem in injection moulding process. To overcome this issue, the use of Response Surface Methodology (RSM) optimisation method to obtain optimal parameters has been introduced which offer better improving warpage defects. This study involving three phases which is designing the parts and cooling channel in the phase I and simulated the flow of melted plastic material into the cavity with Fill, Fill + Pack and Cool (FEM) analysis using Autodesk Moldflow Insight (AMI) 2012 is in phases 2 which is to obtain recommended parameter setting. Lastly, in phases three, simulation works is done with RSM optimisation method to achieved optimum parameter setting and conducting to measure warpage value and the result is compared with the simulation with recommended parameter setting. Four process parameters were considered as a variable factors which are mould temperature, melt temperature, packing pressure and packing time. Design Expert 7.0 software was used to optimise warpage obtained AMI 2012 analysis. The polynomial models are obtained using Response Surface Method (RSM) intergrated with Center Composite Design (CCD) method in this study. The result shows that packing pressure is the most significant factor that contributed to warpage. Result shows that 40% improvement on x direction while 23.7% on y direction in miminise the warpage.