Three Categories Of Plastic Molds

Three categories 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 molding mold is the plastic injection molding machine. The plastic is first heated in the barrel at the bottom of the injection machine. It is heated and melted, and then driven by the screw or plunger of the injection machine, it 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 Mould

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°), then the measured compression molding powder is put into the mold cavity and the feeding chamber, the mold is closed, and the plastic is heated under high heat and high pressure. Soften the viscous flow, solidify and shape after a certain period of time, and become the desired product shape. The difference between injection molding and compression molding is that there is no separate feeding chamber. The mold is closed before molding, and the plastic is preheated in the feeding chamber and becomes 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.

3. Plastic extrusion die

A type of mold used to produce continuous-shaped plastic products, also known as extrusion molding head, is widely used in the processing of pipes, rods, monofilaments, plates, films, wire,  and cable cladding, profiled materials, etc. The corresponding production equipment is a plastic extruder. The principle is that the solid plastic is melted and plasticized under the conditions of heating and the screw rotation of the extruder, and is made into the same cross-section as the shape of the die through a die of a specific shape. Continuous plastic products. Its manufacturing materials are mainly carbon structural steel, alloy tools, etc., and some extrusion dies are also inlaid with wear-resistant materials such as diamond on the parts that need to be wear-resistant. The extrusion process is usually only suitable for the production of thermoplastic products, which is significantly different from injection molds and compression molds in structure.