Solid-wall pipe, manufacture

Another method of manufacture of solid-wall pipe is to extrude and wrap molten sheets or strips of thermoplastic around the outside surface of a tubular mandrel. Where this method is used, this pipe is manufactured to a controlled inside diameter. Continuous fiberglass-reinforced thermosetting resin pipe is generally manufactured in this manner. Some types of spiral-strip-wound composite piping are manufactured by being formed against the inside surface of a tubular fixture. 

---