The air trapping position in cavity and exhaust method

The air trapping in cavity is usually in the following places:

1. Thin-wall structure cavity, the end of melt flow;

2. The junction of two or more melts;

3. The last area where the melt in the cavity reaches;

4. The bottom of the blind hole of the mold cavity is mostly the end of a solid column in the part;

5. Reinforcing ribs of molded parts and the bottom of screw pillars;

6. Dead corners of complex mold cavities.

Exhaust method in injection mold include as following:

1. Parting surface (including venting slot);

2. The fitting surface of insert;

3. The fitting surface of the push rod or pipe with inner mold insert;

4. Exhaust from side core pulling mechanism;

5. Add a vent needle or insert to vent the air in the trapped area;

6. Breathable steel exhaust;

7. Air valve exhaust;

8. The mold is evacuated and exhausted.