It is usually four steps, compression, injection moldin […]
It is usually four steps, compression, injection molding, extrusion molding, and blow molding.
The first step, the compression molding process is also called molding in the industry, and is used for the molding of thermosetting plastics such as phenolic resin, urea-formaldehyde resin, and unsaturated polyester resin.
The second step, the extrusion process, also known as extrusion molding, is a method in which an extruded resin is continuously passed through a die by an extruder to extrude a product of a desired shape. The utility model has the advantages that the product of various shapes can be extruded, the production efficiency is high, and the production can be automated and continuous; the disadvantage is that the thermosetting plastic cannot be widely processed by the method, and the product size is prone to deviation.
The third step, the injection molding process can also be called injection molding. Injection molding is a method in which a thermoplastic melt is injected into a mold under high pressure using an injection molding machine to obtain a product by cooling and solidifying. The advantages of injection molding are fast production, high efficiency, and automation of operation, which is especially suitable for mass production. The disadvantage is that the cost of equipment and mold is high, and the injection molding machine is not easy to clean.
The fourth step, the blow molding process is also called hollow blow molding. Mainly by a method of inflating a hot resin parison closed in a mold into a hollow article by means of the pressure of compressed air, the blow molding comprises two methods of blown film and blown hollow article. The blow molding method is mainly used for the production of film products, various bottles, barrels, pots and the like.