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PA plastic is a versatile engineering plastic with a long history and a wide range of uses. In the spare time, listen to the fairy and say a little about PA plastic molding. Welcome everyone to ask me.

1. Crystallized material, high melting point, narrow melting temperature range, poor thermal stability, decomposition temperature when the material temperature exceeds 300 degrees and residence time exceeds 30 minutes. It is easier to absorb moisture and needs to be dried. The water content should not exceed 0.3%.

2, good liquidity, easy to overflow. Self-locking nozzles should be used and should be heated.

3. The molding shrinkage range and shrinkage rate are large, the directionality is obvious, and shrinkage and deformation are easy to occur.

4. The mold temperature is selected according to the wall thickness of the plastic part in the range of 20 to 90 degrees. The injection pressure is selected according to the type of the injection machine, the material temperature, the shape and size of the plastic part, and the mold casting system. The molding cycle is selected according to the wall thickness of the plastic part. When the viscosity of the resin is small, the injection and cooling time should be long, and white oil is used as a release agent.

5, the form and size of the mold casting system, increase the flow channel and gate size can reduce shrinkage.

The disadvantage of polyamide is that the dimensional accuracy due to thermal expansion and water absorption is insufficient, the acid resistance is poor, and the hardness and elastic modulus are insufficient. After improvement, it is also one of the more excellent engineering plastics.