Exhaust of injection mold is a problem that can not be ignored in mold design. Poor exhaust can cause numerous problems. For example: air holes, holes, burning, air bubbles, silver lines on the surface, obvious fusion wiring, etc.
The built-in gas accumulation in a die comes from the following sources:
Lends air to the system and the cavity.
The plastic contains water vapor, which is formed by evaporating at high temperatures.
The gas is created when plastic breaks down, costing money.
A gas formed by a chemical reaction or evaporation of certain additives in plastic
Chiming in air and water!
The basic design points of injection mold can be summarized as follows:
The exhaust system ensures fast and complete process, and the exhaust speed ADAPTS to the mold filling speed.
According to the principle, the exhaust groove is arranged in the forming part of thick rubber parts as far as possible;
Convex exhaust groove should be set on the parting surface as far as possible;
The exhaust groove should be located at the end and confluence of the material flow, such as the end of the cold material well;
To facilitate mold manufacturing and die cleaning, the exhaust groove should be located on the side of the concave die as much as possible.
The direction of the exhaust groove should not face the operating surface, to prevent leakage and injury during injection molding;
The exhaust groove should not have Angle, to prevent cold material accumulation;
The size of the exhaust groove must be appropriate (the general thickness is about 0.2-0.3mm), according to the specific material and product requirements for processing, as far as possible to avoid flying edge.
Common forms of exhaust are:
A slot or hole exhausts air
The parting face exhausts at a cost
Buy a slot to vent the insert
Either push rod or thimble clearance vent
Sino - combustion powder combined with bullion exhaust
Buy a ticket to force air out using an exhaust rod
A vacuum exhauster is used to achieve active and complete exhaust.
Buy gas die exhaust steel, exhaust plug and so on
For more information, please contact us Claire@proto -mold. com , 86 13662571826