The exhaust system of plastic molds is also very important, if the product has air trapping or exhaust system is not suitable will have a big impact on injection molding production and product quality, especially for predeformation mold, the part size will be different if there is air trapping inside mold, which will cause instability during production.
We must follow the following principles when making the mold exhaust slot:
1. The exhaust must be rapid and complete, and the exhaust speed should be compatible with the filling speed;
2. The exhaust slot (hole) should be made in thicker wall thickness of the plastic part;
3. The exhaust slot should be made in parting surface as much as possible, and it is better to make it on the side of the cavity side(according to the shape, characteristics and mold structure of the plastic part, the position of the exhaust slot is allowed to make in core side);
4. The burrs generated by the overflow of the exhaust slot should not hinder the demolding;
5. The exhaust slot should be made as far as possible at the end of the material flow, such as the end of the runner and slug well ;
6. The exhaust direction of the exhaust slot should be toward the reverse operation surface;
7. Refer to the standard data for the depth of the exhaust slot and the depth of the overflow slot, the width and distance, etc.;
8. The exhaust slot should be polished along the exhaust direction;
9. Exhaust slot must be made at the weld mark area;
10. It is better to make the exhaut slot as deep as possible which can not see the flash, but it will be better to see the flash in runner area.