Plastic General Instability Analysis of Deep Sea Water Pressure Casing

This paper discusses the design and analysis of 6000 meters depth rated pressure casing made of 17-4 PH Stainless Steel grade H900. Analytical calculation and finite element analysis are carried out to predict the buckling behaviour and strength of the pressure casing. The result of numerical analysis shows reduction in buckling pressure while considering geometric and material non-linearities. At critical equilibrium state, a dimensionless number ϕ
t
of a structure is used. From the stress-strain curve of a material, a four-parameter formula that contains ϕ
t
is established. This formula is used for calculating the inelastic buckling of deep sea water pressure casing. The results from analysis show that the selected material and design are acceptable for pressure casing at 600 bar hydrostatic pressure.