Parting surface venting of runner system

There are a large amount of gas in the main and sub channel, these gas are discharged through the pull rod (push rod) during injection processing, a part of gas come out from exhaust slot on parting surface, rest of gas will enter the cavity with plastic melt together, but it is better to have less gas inside cavity to reduce the venting cavity.

The gas in therunner system should be mainly discharged through the parting surface, the exhaust slot of the gating system is mainly opened at the end of the runner, as shown in picture 1.

The exhaust slot design of the runner:

The depth of the exhaust slot (h) is as deep as the flash edge at the end of the runner;

1. Plastic with good fluidity, h≈0.075mm;

2. Plastic with poor fluidity, h≈0.125m;

The width of the exhaust slot is the same as that of the runner, and the entrance should be polished;

The injection pressure at the runner is high, and the exhaust slot should not be facing the operator.