Role of Plastic Injection Moulding, Injection Moulding History and Application

Today injection moulding is an integral process to the mass manufacture of products in the consumer goods, automotive, medical, aerospace, construction and packaging markets. With high production rates, design and material flexibility, low labour cost and minimal wastage it is easy to see how plastic injection moulding is the most common form of part manufacturing.

So how did we get here?
The injection mould process was born in the mid 19th century whereby a cellulose derived material was heated and moulded to retain a solid shape when cooled. The fragile nature of this material limited its uses. American inventor, John Wesley Hyatt creates Celluloid, an improved cheaper, stronger and stable material.

The potential uses of this technology saw Hyatt and his Brother patent the first plastic injection moulding machine in 1872. Although it was but a simple plunger injecting plastic through a heated cylinder, Injection moulding provided the cheap, easy creation of multiple small parts like buttons and hair combs. However, it wasn’t until World War II that the demand for inexpensive, mass production saw the development of the first screw injection machine improving precision and quality of the plastic injection mould process. It was this 1946 amendment by James Hendry that revolutionised the injection moulding industry allowing recycled and coloured plastics to be mixed with the new material before being injected.

Hendry created the first gas-assisted injection moulding process in the 1970s which allowed the quick production of complex, hollow articles. This improvement expanded the uses of injection moulding with increased design flexibility and product strength as well as reducing costs, weight and wastage.

Plastic Injection Moulding uses polymers and thermoplastics. With thousands of different types of polymers and alloys, it is important you consult expert engineers to ensure you have the most appropriate material for your application.

The injection moulding process involves having a complete computer-aided drawing (CAD) of the part and mould in which to create a high quality Plastic Injection Mould for prototyping and production. Once the mould or tool is constructed, usually out of steel or aluminium, the plastic material is heated and mixed. The plastic is then forced into the mould cavity where it is pressurised by the weight of the Injection Moulding Machine. Once cooled, the hardened product can be ejected.

Plastic Injection Moulds can be manufactured for a single or multi cavity production. It is important to get quality prototypes of the part in order to discover costly design faults and mistakes before going into mould or tool production. Stereo lithography (SLA) creates prototypes using CAD and Lasers to build a resin model based on the 3D drawings.

If you are looking for design flexibility, repeatability with tolerances, low labour costs, little to no finishing of parts, minimum wastage with a wide range of material options, than you need Supaflow Engineering. For all your Brisbane Injection Moulding needs, with 25 years experience and high quality customer assurance, Supaflow Engineering is the plastic toolmakers and Brisbane injection moulders for you.