Knowledge of plastic injection process, 8 types of plastic injection process diagrams, how many have you seen?

Plastic is a high molecular weight polymer that can be processed in a variety of ways. Each method has its own advantages and disadvantages and is more suitable for specific applications. Next, let's see how they are handled with their respective cool animations!

Injection molding machine

Injection molding

Injection molding is a manufacturing method in which parts are created by injecting material into a mold. The main method of plastics processing is injection molding. In this process, plastic is placed in a hopper, which then injects heated plastic, which is pushed through a long chamber with a reciprocating screw. After that, it softens to a liquid state. The nozzles are located at end of chamber, through which liquid plastic is forced to cool, closing mold. While plastic cools and hardens, semi-finished product comes out of press.

Plastic extrusion

Plastic extrusion

Plastic extrusion is a high-volume production method in which plastic raw materials are melted to form a continuous profile. The extrusion process is commonly used to produce materials such as films, continuous sheets, pipes, profiles, rods, sheaths, threads, wires and cables. Together with injection molding machine, dry plastic is placed in a hopper and fed into a long heating chamber. At end of chamber, material is extruded from a small hole or mold, taking shape of desired end product. After plastic leaves mold, it is placed on a conveyor belt to cool. Sometimes a blower is used during this process to cool it down.

Blow molding machine

Blow molding

Blow molding is a method of forming hollow plastic products. This is a secondary molding technology that uses gas pressure to inflate a rubber-like preform, closed in a mold cavity, into a hollow product.



A special plastic processing method for processing thermoplastic sheets into various products. The sheet is clamped on frame and heated to a softened state, under action of an external force is pressed against surface of mold to obtain a shape similar to surface. After cooling and setting, it is cut and trimmed. This process is also used in processing of rubber. In recent years, thermoforming has made new advances such as continuous production technology from extruded sheet to thermoforming.

Shaping Compression

Compression molding

Compression molding is most common method used for thermosets and is not commonly used for thermoplastics. During this process, material is extruded into desired shape. Plastic molding powder and other materials are added to mixture to give it special properties. When mold is closed and heated, material hardens and takes desired shape. The temperature, pressure and duration of process depend on desired results.



Also known as calendering. The last process of finishing heavy leather. Using plasticity of fibers under mixed thermal conditions to flatten surface of fabric or roll parallel thin oblique lines to improve process of finishing sheen of fabric. After material is fed, heated and melted, it is formed into a sheet or film, cooled and rolled. The most commonly used calendered material is polyvinyl chloride.



Extrusion molding, workpiece is extruded from hole or gap of mold under action of three-way uneven compressive stress to reduce cross-sectional area and increase length, and processing method to obtain desired product is called extrusion. This processing is called extrusion molding.

Vacuum forming

Vacuum form

Vacuum forming (vacuum forming), often referred to as blister processing, is a plastic processing technology. The basic principle is to heat and soften a flat hard plastic sheet, then with help of vacuum it is absorbed by mold surface and formed. after cooling.It is widely used.Used in plastic packaging, lighting, advertising, decoration and other industries.

Rotational molding

Rotational molding

Rotational molding is also known as rotational molding, rotational molding, rotational molding, rotational injection molding, rotational molding, etc. The rotational molding process is to first add plastic raw materials to mold, and then mold is continuously rotated along two vertical axes and heated, so that plastic raw material in mold is gradually and evenly coated, melted and adhered to mold. under action of gravity and thermal energy, entire surface of mold cavity is molded into desired shape, then cooled and molded, demoulded, and finally a product is obtained.

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