Conduit and method of forming

A method of continuously forming conduit comprising:

• continuously applying at least one thin film ribbon, each having “leading” and “trailing” lateral edges, spirally around a former rotating and advancing said conduit, with the leading edge of each turn of ribbon overlapping the trailing edge of a previous turn of ribbon on the former and the trailing edge of each turn under lapping the leading edge of a succeeding turn, while,
• in advance of said overlapping of said turns, applying a bead of molten plastic, having “leading” and “trailing” edges, adjacent the exposed trailing edge of the most recently applied turn on said former, such that said bead is interposed between the overlapping and under lapping portions, said head when cooled forming a helical reinforcing bead, and wherein
• said overlapping portion is supple, at least laterally, and conforms around the contour of said molten bead as it is applied thereto, such that said overlapping portion continuously contacts said bead and bonds along said conforming portion;
• and said overlapping portion of said ribbon meets or substantially meets said trailing edge of said under lapping portion of said ribbon, at the trailing edge of said bead.