CYCLE TIME OPTIMIZATION AND PART QUALITY IMPROVEMENT USING NOVEL COOLING CHANNELS IN PLASTIC INJECTION MOULDING

摘要

Cooling channel design in injection moulding is very important as it greatly affects the cycle time as well as the shrinkage and warpage of the plastic part. Traditionally, cooling channels have been machined into mould components with gun-barrel drilling, with that only straight channels were possible to manufacture. An advanced method of cooling system that 'conforms' to the shape of the part in the mould can be made possible with free form fabrication technique such as DMD (direct metal deposition). This paper presents an investigation on the optimization of mould design of conformal cooling channels of different cross sections for plastic injection moulding. Comparative study has been done with the conventional straight cooling channels. ANSYS thermal simulation software has been used to get comparative temperature profile on the mould and Moldflow simulation software has been used to compare shrinkage, warpage and temperature profile of the part itself during moulding process . Comparative results are presented based on temperature distribution and cooling time for the mould and warpage deflection, volumetric shrinkage and temperature profile of the part. The results provide a uniform temperature distribution with reduced shrinkage and warpage and reduction in cycle time for the plastic part.