Venting insert design of molded parts

In the thin-walled cavity, the end of the melt flow, the bottom of the blind hole of the mold cavity, the end of the solid column of the plastic part, the bottom of the plastic part rib and screw column, and the corners of the complex cavity are the most where it is easy to cause air trapping, the exhaust in these area mainly depends on the exhaust slot on the shut-off surface between the inserts and the exhaust slot.

Venting design of molded parts:

a. When the end of the material flow is not on the parting surface due to the restriction of the cavity structure, the matching gap between the molded parts can be used to exhaust;

b. Some parts of the forming parts that constitute the cavity, such as ejector rods, ejector pines, moveble parts, etc., the cavity or core are mostly used for clearance fit, and the matching gap is large, if it is designed in the end side of material flow, it can also serve as an exhaust gas, and there is no need to set up an exhaust system at this time;

C. When the exhaust rate cannot meet the requirements, an exhaust structure can be set on the corresponding parts to increase the exhaust rate (see the picture as below);

d. The transitional fitting inserts should have an exhaust slot at the end of the material flow in advance (see the picture as below);

e. The three-stage exhaust slot must be open to the outside of the mold and connected with the air;

f. The exhaust slot between the inserts is easily blocked by plastic powder or mark, and must be cleaned regularly.