Purging

In extrusion or injection moulding, the cleaning of one colour or type of material from the machine by forcing it out with the new colour or material to be used in subsequent production, or with another compatible purging material.

Cleaning one colour or type of material from the cylinder of an injection moulding machine by forcing it out with the new colour of material to be used in subsequent production. Dedicated purging materials are available, that have additives to help clean the internal parts of the injection chamber and check valves.