Fremgangsmåte og innretning ved slipp-kontroll for spiralviklede rör

摘要

PCT No. PCT/AU88/00311 Sec. 371 Date Feb. 16, 1990 Sec. 102(e) Date Feb. 16, 1990 PCT Filed Aug. 19, 1988 PCT Pub. No. WO89/01588 PCT Pub. Date Feb. 23, 1989.A method and means of slip control for helically wound pipes wherein the pipe is formed by helically winding a strip of plastics material and the edges of the convolutions of the strip are interconnected, wherein a slip-control member applied to the interconnected edges of the convolutions of the strip is arranged to be withdrawable progressively from the pipe to allow slip linearly between the interconnected edges of the convolutions of the pipe when torque is applied to the pipe.