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Alvin Pressure Sphere
THis is one of the two titanium pressure hulls designed and fabricated by the Naval Research Laboratory, for use in the US Navy's deep-submergence vehicle, Alvin. Made of titanium 1.92 inches thick and weighing 7,500 pounds, these pressure hulls replace the original one made of 8,500 pounds of steel 1.33 inches thick. The lighter weight and greater strength of the titanium hull not only reduced Alvin's weight by 1,000 pounds but increased its operating depth from 6,000 to 12,000 feet. This sphere was retired after being tested extensively to confirm that design specifications had been met. Its companion was still in operational use aboard the submersible as of September 1982. |