Patent ID: 7004202

Claim:
A composite strip windable to form a helical pipe for transporting fluid, the composite strip comprising: an elongate plastic strip having a base portion having a lower side defining an inner face and an upper side defining an outer face, and at least one lengthwise extending rib portion upstanding from the outer face of the base portion; and an elongate reinforcing strip extending lengthwise and supported laterally by the rib portion, the reinforcing strip having a height measured in a direction orthogonal to the base portion and a thickness measured in a direction parallel to the base portion, the reinforcing strip oriented substantially perpendicular to the base portion and the reinforcing strip having a ratio of the height to the thickness of at least three to one, the inner face forming a continuous surface below the reinforcing strip, wherein, when wound into a helical pipe, the reinforcing strip reinforces the pipe against radial crushing loads and the inner face separates the reinforcing strip from the fluid within the pipe.