The process converts granular or powder raw material such as P.V.C., A.B.S., polyehtylene, polystyrene, polycarbonate and engineering grade thermoplastics into finished or semi-finished goods. End products include tubes, profiles and rods, both flexible and rigid.

The conversion process is achieved by melting a selected thermoplastic material in an "extruder" to generate a continuous melt stream, forcing the molten material through a die, holding the material to a desired finished shape in a sizer while it is being cooled, and then cutting the extrusion to length.