General use of domestic-type pressure cookers.

Plastic materials are heated to such a temperature that they will flow and are then forced under pressure into a metal mould or through a die.

The combustion of any fuel, eg, acetylene, propane or methane, with oxygen from a cylinder rather than air at normal or increased pressure, gives a hotter flame that is often easier to control.

A thermoplastic sheet is clamped around its edges and heated. Some plastics must be pre-heated to dry them.