METHOD OF MANUFACTURING COMBINED PIPES Russian patent published in 1997 - IPC

FIELD: manufacturing polymeric pipes. SUBSTANCE: plastic pipe is set on a mandrel. On the pipe an reinforcing layer is wound. The layer is polymerized and combined pipe is removed from the mandrel. The plastic pipe of the inner diameter smaller than that of the mandrel is simultaneously moulded for the greater diameter and set on the mandrel with a spaced relation. The pipe is conditioned until it abuts against the mandrel. After that the reinforcing layer is wound and polygamized. The finished pipe is then removed from the mandrel. A ring shaped mandrel is used for mandrelling. EFFECT: simplified method. 2 cl, 4 dwg