The type of plastic molding
1. Extrusion is a method of heating, pressing, and making the plastic flow state continuously through the mouth. Generally used in sheet, pipe, wire, tape, film, wire and cable coating molding, wide application, high yield. As a result, it is one of the important forming methods of plastic addition.
2. Foam molding is a foaming material adding proper foaming agent, can produce porous or foam products and foam products with relatively low density, high specific strength, low consumption of the raw materials and sound insulation, thermal insulation, such as V, foam PVC, PE and PS and other. Products are: film, sheet, pipe and profiles, etc.. Foaming can be divided into chemical foaming and physical foaming.
3. Blow molding blow (expansion) film plastic (or blow molding is referred to by means of a fluid (compressed air) pressure will be closed die heat thermal plastic plastic preform or sheet blown into a forming method of hollow products.
Plastic containers made of this kind of method, such as a variety of bottles, square, round or flat barrel, gasoline tank, etc. have been widely used. New development of various industrial parts and household products, such as double walled box products, l ring big drum, plate stacking, surfboard, backrest and a desk, and automotive front spoiler, the belt cover, instrument panel, air conditioning and ventilation tube has in practice applications, industry and trade of materials from daily plastic to the development of engineering plastics. Now blow molding process has become one of the important methods of plastic processing.
But the basic step of the blow molding process is: 1) melting material. 2) to form a tube or a type of a tubular material. 3) hollow parison mold sealing. 4) to blow up the mold. 5) cooling blow molding products. 6) remove the product from the mold. 7) dressing.
4. Injection blow molding injection blow molding is a blow molding method. The first plastic type bottom slab by injection molding, and then moved to blowing mold blown into the hollow products. This method can be used in the production of daily necessities, cosmetics, medicine, food and other packaging containers. But its volume should not exceed 1L. Commonly used plastics, such as polyethylene, polystyrene and polyvinyl chloride.
5. Extrusion blow molding extrusion blow molding method. Different from injection blow molding. Its type is made of extrusion.
6. Stretch blow molding is a blow molding method. It is used in extrusion, injection molding, etc.. Then the parison heating to the stretching temperature, the internal (such as the mechanical force of the mandrel) or external (such as fixture) and the longitudinal tensile. At the same time or later by a compressed air blown and transverse tensile.