A.H Behravesh - Mechanical Engineering Department,Tarbiat Modarres University, Tehran, Iran
H Motabar - Mechanical Engineering Department,Azad University, Science and Research Centre,Tehran, Iran

An experimental investigation is presented on shrinkage of injection molded part and its relationship with gate design and processing parameters. Accuracy in molded parts is directly related to the accuracy of shrinkage prediction. Although, the effects of processing parameters on shrinkage have been well explored, the studies on influence of mold design have not been reported extensively. In this research work, the effect of gate dimention on final shrinkage and its relation with holding pressure and time are investigated. The results have been explained using PVT diagram, showing that an optimum gate dimention can be achieved to yield minimum shrinkage.

Injection molding, Gate, Shrinkage, PVT