Plastic injection molding is the method of manufacturing parts made of thermoplastic and thermosetting plastic by melting and forcing into molds where they cool to form the desired object.

Little history about Plastic injection molding

The injection molding process is not a new concept. It came into existence by 1872. By the introduction of plastic injection molding, the plastic industry saw multi-billion dollar earnings, with 32 % of all plastics, by weight processed by injection molding. This has made the plastic injection molding the best molding method ever available.


Raw Materials

There are several kinds of raw materials used for the manufacturing of the plastic injections. However, the thermosetting plastic, elastomers and thermoplastic polymers (resins) are widely used in the production process due the presence of greater viscosity in these materials.



The Plastic injection molding machines have basic component parts such as material hopper, heating unit, plunger etc. These machine parts are used to build pressure and keep the molds in proper order to give the perfect shape once the molten material is poured inside it. They are also called presses, working in accordance with the tonnage ratings. Tonnage is the capability of the machine to exert clamping force during the manufacturing process to keep the molds in closed position. The tonnage may range between 5 tons to more than 9000 tons depending upon the rigidity of the raw materials and the projected area of the molding parts.


Plastic Injection Molding Process

Melting Polymers: There is a broad and cylindrical melting unit in the injection molding machine, where the polymer is converted into liquid under high temperature and pressure. The polymer is filled in an auger, which has an opening at the bottom. The auger is introduced into the melting unit using a hydraulic motor. A valve system at the bottom of the cylinder restricts the passage of the liquid into molds.


Pouring the Liquid into the Molds

Once the heating process is over, the auger is pushed further to pour the liquid polymer in to the molds to give the requisite shape to the injections. The molds are compressed under huge pressure to keep them intact and in proper position. During this process, the liquid is poured twice or more to ensure there are no air spaces left.



After the molding, the entire mould is introduced to cooling for compact solidification of the plastic injections, which consumes the major time-period during the entire manufacturing process. The cooling is done by passing air or water over the heated molds or introducing cold water through small holes on the mold surface.



Once the cooling process is over, the compact plastic injections are ready for removal from the molds. The clamp on the mould is unlocked to open the mould and derive the injection. The entire process is completed and the mold is now ready for the next unit manufacturing.


                                                                                                      by China mold maker



About JasonMould Industrial Company Limited:

JasonMould is one of the best plastic injection molding manufacturer that offer great services to their clients when it comes to manufacturing advanced molding tools. They export their tools to different parts of the world and have become one of the most famous names in the industrial sector.

Inquiry Contact:

Contact person: James Yuan

Company name: JasonMould Industrial Company Limited

Address: LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong Province, China

Telephone: 86-752-6682869

Email: [email protected]

Website: https://www.jasonmolding.com

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