The Most Widespread Science of Manufacturing Plastics 

Injection Moulding is a manufacturing process for producing parts by injecting melted material into an injection mould. Injection moulding is widely used for manufacturing a variety of plastic parts, from the smallest components to entire body panels and bumpers for cars.

American inventor John Wesley Hyatt, together with his brother Isaiah, patented the first injection moulding machine in 1872.

Injection moulding is used to create many things such as, packaging, automotive parts and components, toys, storage containers, mechanical parts, and most other plastic products.

Process Steps

• Designing the part and making a mould from steel or aluminium.
  
  
• Feeding the plastic material into a barrel.
  
  
• Mixing the melted plastic material using a helical shaped screw.
  
  
• Injecting melted plastic material into a mould cavity where it cools and hardens to the form desired.

Advantages

• Switching from aluminium/metal to plastic.
• Can produce a large number of parts of the same kind.
• Plastic material is lighter than aluminium/metal.

Disadvantages

• Not all the metal/aluminium parts can be made in plastics.
• Environmental impact.
• Relatively high cost of investment for the equipment.

Examples of applications

The diversity of the applications, where the parts manufactured by injection moulding are used, makes this technology the most common modern method of manufacturing plastic parts.

It is ideal for producing high volumes of the same part; over 1 million of shots can be performed with a mould, nowadays.