


Basic explanation & schematic view -
injection moulding process |
|
|---|---|
| The injection moulding process involves heating & injecting plastic material under pressure into a closed metal mould tool. The molten plastic cools & hardens into the shape inside the mould tool, which then opens to allow the mouldings to be ejected or removed for inspection, delivery or secondary operations. |
|
injection moulding process - stage 1![]() |
Material granules from the hopper feed into the heated barrel & rotating screw. Material melted by heat, friction & shear force is forced through a check valve to the front by the rotating screw. |
injection moulding process - stage 2![]() |
Having been moved backwards by the shot of material at the front, the screw is forced forward by a hydraulic ram. This action injects material into the mould cavity in the closed mould tool. |
injection moulding process - stage 3![]() |
The tool is held closed under pressure until the plastic material cools & sets hard in the mould tool cavity. This is often the longest part of the injection moulding process |
injection moulding process - stage 4![]() |
The screw starts to move back for the next moulding. The tool then opens & the finished plastic part is ejected. The tool is closed and the injection moulding process starts again at 1. |
| Further help with injection moulding process and other help & advice is available from our help page. | |