A plastic mold is a tool that is matched with plastic molding machines in the plastic processing industry to give plastic products a complete configuration and precise size. Due to the variety of plastic varieties and processing methods, and the complex and simple structures of plastic molding machines and plastic products, the types and structures of plastic molds are also diverse.
The main classification of plastic molds
1. Plastic injection (plastic) mold
It is mainly a molding mold that is most commonly used in the production of thermoplastic parts. The processing equipment corresponding to the plastic injection mold is a plastic injection molding machine. The plastic is first heated and melted in the heating barrel at the bottom of the injection machine, and then the screw Or driven by the plunger, enters the mold cavity through the injection machine nozzle and the pouring system of the mold, and the plastic is cooled and hardened to form and demolded to obtain the product. Its structure usually consists of forming parts, pouring system, guiding parts, pushing mechanism, temperature regulation system, exhaust system, supporting parts, and other parts. The manufacturing materials usually use plastic mold steel modules, and the commonly used materials are mainly carbon structural steel, carbon tool steel, alloy tool steel, high-speed steel, etc. The injection molding process is usually only suitable for the production of thermoplastic products. The plastic products produced by the injection molding process are very wide, ranging from daily necessities to various complex machinery, electrical appliances, and transportation parts. It is the most widely used processing method in the production of plastic products.
2. Plastic compression mold
Including compression molding and injection molding two structural mold types. They are a type of mold mainly used to mold thermosetting plastics, and their corresponding equipment is a press molding machine. Compression molding method According to the characteristics of the plastic, the mold is heated to the molding temperature (generally 103°-108°), and then the measured compression molding powder is put into the mold cavity and the feeding chamber, the mold is closed, and the plastic is under the action of high heat and high pressure. It is a softened and viscous flow, and after a certain period of time, it will be solidified and shaped into the desired shape of the product. The difference between injection molding and compression molding is that there is a separate feeding chamber. Before molding, the mold is closed first. The plastic is preheated in the feeding chamber and is in a viscous flow state. Under the action of pressure, it is adjusted and squeezed into the mold cavity to harden and form. Compression molds are also used to form some special thermoplastics such as hard-to-melt thermoplastics (such as polyvinyl fluoride) blanks (cold pressing), resin lenses with high optical properties, slightly foamed nitrocellulose car steering wheels, etc. . The compression mold is mainly composed of cavity, feeding cavity, guiding mechanism, ejecting parts, heating system, etc. Injection molds are widely used in packaging electrical components. The materials used in the manufacture of compression molds are basically the same as injection molds.