Injection Moulding: A Manufacturing Processes

Published: September 23, 2020

Metpro can offer a variety of moulded plastic, nylon and rubber based components using a broad range of processes.

High / Low Pressure Moulding

Molten plastic is injected into a heated plastic mould cavity until cooled.

Blow Moulding

Designed for creating hollow objects, blow moulding sees molten plastic blown into the cavity of a mould with the air pressure forcing the material to the sides of the cavity forming the desired shape.

Compression Moulding

Ideal for more complex parts and working with advanced composite plastics, the compression moulding process introduces molten plastic into an open die cavity. Closed with a top plug, the mould is then compressed, forcing the material into all areas of the mould and forming the desired shape.

Film Insert Moulding

Designed to incorporate labelling and graphics into the moulded component, film insert moulding produces products of extremely high durability and offer scratch resistant coats, as seen in car radio fascia’s and mobile phone covers.

Gas Assist Moulding

Developed to counteract the risk of sink marks following material contraction, gas assist moulding utilises Nitrogen which is injected into the molten material centre once it has been poured into a mould cavity.

Rotational Moulding

Similar to a casting process, rotational moulding or rotomoulding is another option for the creation of hollow products. Powdered plastic is poured into the mould which is then heated. The mould rotates, forcing the powder into all areas of the mould. Cool air is then introduced to solidify the product before moving onto the next phase of manufacture.

Structural Foam Moulding

Similar to a standard injection moulding, foam mouldings are produced using much less pressure with this process used mainly for the manufacture of large structural parts. Parts produced using this process are likely to have thick walls with a lightweight design.

Vacuum Moulding

Using sheets of plastic as the workpiece, each sheet is heated to a set temperature before being stretched onto a mould. A vacuum then forces the plastic against the mould and left to cool.

Powder Metallurgy Plus Sintering

Taking plastic alloy powders, these are mixed together and compacted into a die before being heated and forming the desired shape through the metallurgical bonding of the particles.

Extrusion Moulding

Ideal for tube shaped products, molten plastic is forced through a frame or pattern, creating the desired shape as the material works its way through the die.