Extrusion is a very similar process to injection moulding but uses a die instead of a mould. The shaped die produces continuous lengths of a thermoplastic product.
Extrusion produces products such as guttering, uPVC windows and pipes. The typical plastics used are PVC (polyvinylchloride), Nylon and Polythene.
- The thermoplastic granules from the hopper fall onto the Archimedean screw.
- The rotation screw takes the plastic past the heater.
- The molten plastic is passed through the die and is cooled.
- The process is continuous.
- The product is cut into the desired size later on in the process.
- Extruded products are usually simple shapes.