Compared with other polymer molding methods, extrusion molding has many outstanding advantages.
(1) Continuous production The pipes, plates, bars, profiles, films, cables and monofilaments of any length can be produced as required.
(2) High production efficiency The single machine output of the extruder is relatively high. For example, an extruder with a diameter of 65 mm can produce polyvinyl chloride films with an annual output of 450 tons or more.
(3) Wide range of applications This processing method is widely used in the processing of rubber, plastics, and fibers, especially plastics, and almost all thermoplastics and some thermosetting plastics can be processed by this method. In addition to direct molding products. It can also be used for mixing, plasticizing, granulating, coloring, forming blanks, etc., such as extruders and calenders, can produce calendered film; with the press, can produce a variety of press-molded parts; and blow molding Machines can produce hollow products. In the production process of rubber products, the extrusion method is used to manufacture treads, inner tubes, hoses and various complex cross-section products and semi-finished products such as hollow, solid, and rubber, and can also be used for continuous mixing of filter plastics and raw rubber. Plastics and granulation and other uses. In the petrochemical plant, in the process of producing the resin, the moisture in the resin may be squeezed by an extruder, and the mixing of the additives and modifiers in the various brands of resins may be completed by an extruder to complete the granulation process of the resin.
(4) Multi-use One extruder can process a variety of materials and a variety of products. As long as the different screw and head are replaced according to the material performance characteristics and the shape and size of the product, different products can be produced.
(5) Simple equipment and low investment Compared with injection molding and rolling, extrusion equipment is relatively simple, manufacturing is easy, equipment costs are low, and installation and debugging are more convenient. The equipment has a small footprint and relatively simple requirements for factory buildings and supporting facilities.
The above advantages determine the important position of extrusion molding in polymer processing. The production of plastic products that are completely used or that contain an extrusion process in the process accounts for about half of the total volume of thermoplastic products. Products formed by this method have applications in industrial sectors such as agriculture, construction, petrochemicals, machinery manufacturing, medical devices, automotive, electronics, and aerospace.