Patent ID: 7641949

Claim:
An improved composite over-wrapped pressure vessel having a thin wall, a hollow center and a longitudinal axis; said thin wall comprising a composite material having fibers disposed in a resin matrix, the improvement comprising at least a first and a second set of fibers of different types; said first and second sets of fibers of different types are mixed together; one layer of said first and second sets of fibers are helically oriented with respect to said longitudinal axis; and a second layer of said first and second sets of fibers are hoop oriented with respect to said longitudinal axis; said second set of fibers comprise about 5% to 55% fiber weight of said first and second sets of fibers; said first set of fibers selected from the group consisting of: carbon, high strength carbon, and steel; and said second set of fibers selected from the group consisting of: glass, long-chain polyamide, liquid crystal polymer, polyethylene, metal, crosslinkable elastomer, crosslinkable thermoplastic, crosslinkable thermoplastic elastomer, p-phenylenebenzobisoxazole, Poly{2,6-diimidazo[4,5-b4′,5′-e]pyridinylene-1,4(2,5-dihydroxy)phenylene}, (PIPD) (M-5), polyaramid polyparaphenylene terephthalamide, ultra-high-molecular-weight polyethylene and polyester-polyarylate.