US Patent:
20110180548, Jul 28, 2011
Inventors:
Bruce E. Urband - Houston TX, US
Harrell D. Lusk - Conroe TX, US
Andrew Stephen Ayer - Spring TX, US
Kaushik Mallick - Thornton CO, US
International Classification:
F17C 1/00
B21D 37/16
Abstract:
A pressure vessel may be formed from a thermally processed metal tube. The thermally processed metal tube may be seamless with a large length to diameter ratio. End portions of the thermally processed metal tube may be formed at a first temperature below the lower critical temperature by a load less than about the ultimate stress of the metal. After forming, the end portion may be thermally reconditioned at a second temperature below the lower critical temperature to relieve stress and approach similar material properties as the thermally processed metal tube.