When is plastic injection moulding used

Plastic injection moulding is one of the most versatile methods of manufacturing plastic parts and components.  Plastic parts made by this method can be found across all industries, from large OEMs through to start-ups. It is typically used when large quantities of parts need to be produced with high precision and consistency. This process can be used to create complex shapes, intricate geometries and fine details, making it a versatile process that is used in a variety of industries including automotive, consumer, medical, packaging, utilities, aerospace and defence and leisure.

Plastic injection moulding is typically used when the production volume is high, and the parts need to be manufactured with tight tolerances. The process involves melting plastic pellets and injecting the molten plastic into a mould cavity. The mould is then cooled and the plastic solidifies into the desired shape. The mould is then opened, and the finished part is ejected.. The mould is typically made from steel and is designed to withstand high pressures and temperatures.

There are several advantages to the injection moulding process. Production is fast and capable of producing very high volumes while maintaining tight tolerances and consistent quality.  There is little to no finishing of products as long as the design for manufacturing process is followed.  Injection moulding can be used with a wide range of thermoplastic materials, including commodity plastics, engineering plastics, and high-performance plastics, this allows for the production of parts with a wide range of properties, such as strength, stiffness, toughness, and temperature resistance. Injection moulding generates less waste than other manufacturing processes, as the excess material can be recycled and reused in the production process.  The disadvantages include the high cost of the machinery required to produce the parts and the initial outlay for moulds is high so doesn't always cost in at low quantities.

Plastic injection moulding is often preferred over other manufacturing methods because it is highly efficient and can produce parts with a high level of repeatability and consistency. It is also a cost-effective process for producing large quantities of parts, as the tooling costs can be spread over the production run.

Rutland Plastics has been in the injection moulding business for over 65 years.  This history means that we are recognised as one of the leading experts with experience of working across almost every application and with almost every thermoplastic and additive available.

Free design guide

Rutland Plastics has produced a free Design Guide to help you with all aspects of designing for plastic injection moulding.
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We can provide advice and quotes on anything from a simple sketch to a 3D computer model. Most drawing formats can be handled although we find STEP, Parasolid and DXF translate most successfully.