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injection molding

It is a method that the plastic material is heated and melted in the heating barrel of the injection molding machine, and then the melt is pushed into the mold cavity of the closed mold through the reciprocating screw for molding.

It can not only produce high-precision and high-quality products with high productivity, but also has a wide range of processable plastics with large output (accounting for about 1/3 of the total plastic). Therefore, injection molding is one of the important molding methods in plastic processing.

Extrusion molding

Extrusion is a method of continuous molding of plastic through a die in a flowing state by heating and pressurizing in an extruder.

It is generally used for the molding of coatings such as plates, pipes, monofilaments, flat filaments, films, wires and cables. It has a wide range of applications and high output. Therefore, it is one of the important molding methods in plastic processing.

Foaming molding

It refers to the processing method of adding appropriate foaming agent into foaming materials to make porous or foam products. Foaming products have the advantages of low relative density, high specific strength, less consumption of raw materials, sound insulation, heat insulation and so on. Foaming materials include PVC, PE and PS.

Products: film, plate, pipe, profile, etc. Foaming can be divided into chemical foaming and physical foaming.

Blow molding

Blow molding (film expansion) molding (or hollow blow molding) refers to a molding method in which the thermoplastic parison or sheet in the closed mold is blown into a hollow product by fluid (compressed air) pressure.

Plastic containers produced by this method. For example, various bottle types, square types, barrels or flat barrels, gasoline tanks, etc. have been widely used. Newly developed industrial parts and daily-use products, such as double wall box products, L-ring barrels, palletizing boards, surfboards, seat backs and desks, as well as front chocks for automobiles, belt covers, instrument panels, air conditioning ventilation pipes, etc., have been applied in practice, and processing materials have developed from daily-use plastics to engineering plastics. Now blow molding has become one of the important molding methods in plastic processing.

But the basic steps of blow molding process are:

1. Molten material.

2. The molten resin is formed into tubes or parisons.

3. Melt and seal the hollow parison in the blow mold.

4. Blow the parison in the mold.

5. Cool blow molded products.

6. Remove the product from the mold.

7. Trim.

Injection Blow Molding

Injection blow molding is a blow molding method. The plastic is first made into a bottomed parison by injection molding, and then transferred to a blow molding mold to blow molded into a hollow product.

This method can be used to produce packaging containers for daily necessities, cosmetics, drugs, food, etc., but its volume should not exceed 1L. Commonly used plastics include polyethylene, polystyrene and polyvinyl chloride.

extrusion blow molding

Extrusion blow molding is a blow molding method. Unlike injection blow molding, its parison is made by extrusion.

stretch blow molding

Stretch blow molding is a blow molding method. The parison is made by extrusion and injection molding, and then heated to the drawing temperature. Longitudinal stretching is carried out by internal (such as mandrel) or external (such as fixture) mechanical force, and transverse stretching is carried out by compressed air inflation at the same time or later.