The Mold steel of the plastic chair mold is generally P20 or 718H. After forging, CNC milling roughing, tempering to 30-34HRC (generally not nitrided), CNC milling and other machining processes. The plastic used for plastic injection chairs is usually PP, and sometimes calcium carbonate (not more than 20%) is used to make the product look full and no microcosm. PC (all-transparent) plastic is also used, but many bubbles may occur due to poor exhaust gas, but the cost is high and the surface treatment of the steel material is also different.
The plastic chair mold is generally a large sprue with a cold runner. It is ejected with a thimble. If it is removed with a robot, the top is the top, and if it is automatic, it is a top down.
The chair mold has several special requirements:
1. Haf line is better, do not wear hands;
2. The exhaust effect is better, otherwise the plastic products will have black spots, etc., serious will burn;
3 superimposed effect is better, The stack of 10 chairs does not incline vertically, and the distance between the two chairs should not exceed 60mm when superimposed, and the stacking should be easy to separate;
4. The mold should be highly polished because the chair is a daily necessities, so there can’t have flashes, burrs, etc,so as not to scratch the skin.