The intricacies of the Plastic Injection Moulding Process

Plastic is a very widely used material that has acquired popularity owing to its diverse usability and durability. It is possible to mould plastic to any form and produce products that cater to a wide category of consumer demand. This has led to the formation of a plastic based industry that serves the demands of its client on the basis of mass production. One of the most used methods of mass production of plastic is the Plastic Injection Moulding system. A comparatively old method, this has been in use since the 1800s and has acquired a certain credibility among manufacturers.

Plastic injection Moulding is a very simple process and can be used in the production of material that range from small bottle caps to entire body equipment of cars. Although the process is simple, its machinery is fairly complex and requires a certain degree of specialization for its manufacturing and handling. The Plastic Injection Moulding process was invented by John Wesley Hyatt in 1868, by using a plunger method. The technology for this process has now evolved.

Most manufacturing units make use of heated barrels where the liquefied plastic is fed. It is mixed with plastic granules and forced to form a mold cavity. Once this happens, the molded cavity is cooled and then hardened. The clamping part of the machine then goes on to mould the plastic into desirable shape. The engineer can then design the mould and then the mold is manufactured by the company in iron or aluminium to make suitable parts in precision machines.

Plastic Injection Moulding is used in the production of almost all the household appliances that are used today. This is the most preferred method in manufacturing such idle parts in large volumes. The low cost of labour, ability to use material in various ways, minimal scrap losses are the advantages gained by the use of Plastic Injection Moulding. There is also the development of high tolerance during the manufacturing process. The thickness of the mould is one important aspect that needs to be taken into consideration. Normally a mould with a set thickness is preferred.This prevents any change in the mechanical properties of the plastic.

The material used for moulding has to be assessed for its strength and function and the different parameters required are to be taken into account before going into production. Materials mainly used in the Plastic Injection Moulding process are thermoplastics or thermosetting plastics. Both are types of polymers. Nylon, polyethylene and polystyrene are some of the widely used thermoplastics while vulcanized rubber and bakelite are more used as thermosetting plastics.

Injection moulders use materials from a varied source to produce a varied amount of products. In the 1990s there were about 18000 materials used in production, and it has kept on increasing at the rate of 750 materials every year. The materials are chosen by the product designers in accordance with the products they intend to produce.