Abstract: A process of making a continuous thermoplastic helical seam profile pipe. The thermoplastic material is extruded through a die to form a continuous square tube. The continuous tube is cooled and a filler material is applied. The continuous tube bearing the applied filler material is helically wound to form turns of wound continuous tube. Each turn of the continuous tube is pressed into the preceding turn on the mandrel for adhering the turns together to form the pipe. Apparatus for producing a helical seam profile pipe includes a frame, and a mandrel mounted on the frame for rotation on the frame about a longitudinal axis of the mandrel to helically wind the thermoplastic tube around the mandrel. A source of filler material, and a filler material applicator located adjacent to the mandrel continuously apply a bead of the filler material to the thermoplastic tube prior to being wound on the mandrel.

Abstract: A process of making a continuous thermoplastic helical seam profile pipe. The thermoplastic material is extruded through a die to form a continuous square tube. The continuous tube is cooled and a filler material is applied. The continuous tube bearing the applied filler material is helically wound to form turns of wound continuous tube. Each turn of the continuous tube is pressed into the preceding turn on the mandrel for adhering the turns together to form the pipe. Apparatus for producing a helical seam profile pipe includes a frame, and a mandrel mounted on the frame for rotation on the frame about a longitudinal axis of the mandrel to helically wind the thermoplastic tube around the mandrel. A source of filler material, and a filler material applicator located adjacent to the mandrel continuously apply a bead of the filler material to the thermoplastic tube prior to being wound on the mandrel.