Towards economic design of a pressure vessel made of duplex stainless steel

The feasibility of manufacturing pressure vessels from duplex stainless steel (grade EN 1.4462, duplex 2205: 0.02%C, 22%Cr, 5.7%Ni, 3.1%Mo, 0.17%N) was evaluated by measurements of the mechanical properties of the parent metal and welds, and by finite element modelling. The tensile stress-strain properties of 4 mm sheet, and of the weld metal and the HAZ were measured in the transverse and rolling directions. Behaviour under biaxial stress was studied by pressurising circular sheet specimens from one side only, and measuring the strain as a function of applied pressure. The specimens included parent metal, and sheet with welds and a nozzle attached by welding. These specimens, and a cylindrical pressure vessel with hemispherical ends and a central nozzle, were modelled by finite element analysis. The results are discussed in relation to the current requirement for duplex stainless steel to be classified as a ferritic steel for design purposes.Godkänd; 2005; Bibliografisk uppgift: CD-ROM; 20070525 (ysko