Compliant underwater pipe system

A compliant pipe system for use under water for the transfer of fluids therethrough comprising inner and outer compliant pipes having cylindrical surfaces positioned in substantially coaxial and in substantially close relation with each other a plurality of longitudinally separated wall means extending transversely between said cylindrical surfaces forming a plurality of substantially elongated and longitudinally disposed chambers between said pipes for receiving a buoyancy affecting fluid therein, said inner compliant pipe forming a fluid passageway for the transfer of fluid from a lower area to substantially the surface thereof;

• and wherein each of said compliant pipes consists of a plurality of layers of elastomer material forming a sandwich, each layer consisting of a plurality of strips of elastomer material having substantially high strength filaments embedded therein, said strips of elastomer material bonded together in helices, the helix of one layer spiralling in substantially the opposite direction of at least one other layer;
• and further comprising a longitudinal layer forming part of said sandwich with said longitudinal layer having said strips of elastomer material extending longitudinally in said compliant pipe;
• and further in combination with valve means mounted on said cylindrical surface of the outer compliant pipe at the position of each chamber for filling and emptying said chambers of said buoyancy affecting fluid.