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What are the principles for selecting gate locations for plastic product manufacturers?

The principles for selecting the gate location of plastic product processing manufacturers are as follows:

The location of the gate has a significant impact on the deformation of the injection molded part, and has a direct impact on the quality of the injection molded part. Improper selection of the gate location will cause deformation and many other defects of the injection molded parts. The choice of gate location mainly depends on the shape and requirements of the injection molded part, and generally has the following principles.

1. The principle of large wall thickness and consistent flow: The selection of the gate location should be set at the maximum wall thickness of the product, so that the plastic melt flows from the thick wall to the thin wall; It is also necessary to maintain a basically consistent flow from the gate to the various cavities.

2. Principle of material flow downstream: The gate position should be selected at the top of the plastic product to fill the material flow downward from the top of the product. It is not allowed to set it at the middle end of the injection molding part, let alone at the lower end of the injection molding part, so that the material flow is filled from the middle and lower ends of the injection molding part in a countercurrent manner.

3. The material flow flows from the open part of the mold cavity to the narrow part. In principle, the gate location should be selected at the open part of the mold cavity, and it should also be avoided that the material flow directly impacts the mold core to produce flocculent flow and cause flow marks on the outer surface of the injection molded part.

4. Principle of preventing material loss and stable flow The plastic product processing factory should prevent spray at the polyester outlet, which may cause serpentine flow or concentrated flow during the filling process.

5. Set in the main stress direction In principle, the gate position should be set in the main stress direction of the injection molding part, because the tensile and compressive stresses borne in the flow direction of the injection molding material are the largest, especially for reinforced plastics with additives.

6. The principle of avoiding weld marks at a higher strength of injection molded parts When selecting a location, plastic product manufacturers should consider the size and accuracy of the injection molded parts, the shape and shrinkage directionality, the weld mark location, and the fiber directionality of the injection molded parts. Because the flow direction of the plastic body and the shrinkage perpendicular to the flow direction are different, their deformation, shrinkage, and fiber directionality are also different, and the strength at the weld mark is also different, Welding marks should be avoided at places with high stress on injection molded parts, and the fewer the number of welding marks, the better.

7. The principle of short flow and low kinetic energy and pressure loss: The gate position of the plastic product processing factory should make the material flow short, which is conducive to the discharge of cavity gas, and minimize changing the direction of the material flow. As well as the loss of kinetic energy and pressure of the material flow, it is also necessary to avoid the material flow directly impacting the core or insert.

8. Appearance and Easy Removal of Gate Condensate Principle The surface of injection molded parts with high appearance requirements should not be equipped with gates, and the removal of gate condensate should be convenient.