Plastic Injection Mold Gate Types- Taizhou Huangyan Aoxu Mould Technology Co., Ltd.

Plastic Injection Mold Gate Types

03-04-2023

Mold gate, or called feed inlet, is a slender and short runner which connecting the sub-runner and cavity part(except direct gate), and is a important part in gating system. The main functions are: when cavity is fulled with melted material, the gate part solidify firstly to avoid material backflow, and then it can be cut easily after producing. Four types of gate:

1. DIRECT GATE

Direct gate, also named center gate, which has low flow resistance with fast speed of feeding, is used in single cavity molds with large size and deepth. It's suitable for the material with high viscosity and poor mobility, such like PC, PSF, etc.

If making shallow and flat product with direct gate, the product will be bent and warping, also there will be obnious gate marks on the product. Sometimes if the heat focus on the gate part, the inner pressure is large which will cause crack. So when designing, the gate should be small. For thinwall mold, the max gate diameter should be twice of wall thickness.

2. SIDE GATE

Side gate, also called edge gate, is made on the joint face with rectangular section, which is suitable for multi-cavity molds.

3. PIN-POINT GATE

Pin-point gate, also called pin gate, is a very small size gate. This kind of gate type is widely used in all kinds of shell molds which need cutting gate easily. But it's not suitable for large wall thickness product because the cross sectional area is small and condensation is fast.

4. SUBMARINE GATE

Submarine gate, same named shear gate, is evolved from pin-point gate. Pin-point gate is used for three plate mold, but submarine gate is used for two plate mold to simplify the mold structure. This kind of gate is designed on product inner side or outside hidden place, which won't influence the beauty of product. When ejecting the product, the gate will be cut, so it's not good for some coriaceous material.