Concentric shells for compressed gas storage
Gas containment vessels are provided that are comprised of an inner corrosion resistant shell made of lower strength steel alloy or aluminum alloy or thermoplastic polymer, and an outer concentric shell constructed of high strength, albeit lower corrosion resistant, metal or fiber-reinforced composite. The fiber can comprise filaments derived from basaltic rocks, the filaments having been immersed in a thermosetting or thermoplastic polymer matrix, and commingled with carbon, glass or aramid fibers such that there is load sharing between the basaltic fibers and carbon, glass or aramid fibers.
1. A high pressure gas storage vessel, comprising:
an inner shell made of corrosion-resistant, low strength alloy steel or aluminum alloy having approximately 700 MPa tensile strength, wherein the inner shell material is corrosion-resistant to natural gas or hydrogen fuel; and
a concentric outer shell made of high-strength steel wires that are protected from external corrosion by immersing in a polymer matrix, with the steel wires wrapped over the inner shell;
wherein the inner shell has a straight cylindrical portion and opposite end dome portions; and
wherein the steel wires are wound partially just over the straight cylindrical portion and not over the entire shell including the end dome portions.
2. The vessel of claim 1 , wherein the inner shell comprises 4130 alloy steel.
3. The vessel of claim 1 , wherein the inner shell comprises 6061 aluminum alloy.
4. The vessel of claim 1 , wherein the polymer matrix is selected from the group consisting of thermosetting polymers such as epoxy and vinyl ester, and thermoplastic polymers such as polyethylene and polypropylene.