Lining sewage pipe with thermoplastics - by placing extruder in pit at one end of pipe, extruding thin-walled tubing inside pipe and pressing it against pipe with compressed air

摘要

Pipes lined with thermoplastics are produced using pipes whose i.d. holds the plastic material which is applied in the form of tubing and is bonded to that i.d. The process uses granules of plastics and extrudes the tubing inside the pipe; air supports the tubing which is bonded to the pipe, and the extruding plus bonding are continued along the whole length of the pipe. The process pref. uses polyethylene granules and bonds them to the pipe with a polyethylene foam. ADVANTAGE - The procedure is a simple way of reconditioning sewage pipes. It seals the inside face of raw pipes with the polymer used and does so regardless of the condition of the interior of the pipes beforehand.