New Steel Plate for LNG Storage Tank

Abstract

A new low-nickel (6.0-7.5%Ni) steel plate for LNG storage tanks has been developed with performance equivalent to 9% Ni steel, which has been used for LNG storage tanks for several decades. This excellent performance equivalent to 9% Ni steel was achieved by reducing the amount of added nickel, optimizing the chemical composition, and by applying the latest Thermo-mechanical controlled process (TMCP) technology to the steel plate, in order to contribute to cost savings and natural resource savings. Developed steel has been practically applied through joint research with customers and committees, and the expansion of its applications is progressing.

Effects of the Addition of Alloying Elements on Hydrogen Diffusion and Hydrogen Embrittlement in Martensitic Steel

“…In many low-alloyed high strength steels, alloying elements are added at a mass percentage below 1%. Conversely, high-alloyed steels, such as martensitic stainless steels, [9][10][11][12] high Ni-containing martensitic steels used for liquid natural gas storage, 13) and transformation induced plasticity (TRIP) steels [14][15][16] employed in automobile bodies, contain a significantly higher mass percentages of alloying elements more than several mass%. In this study, we examined high-alloyed martensitic model steels with alloying elements surpassing several mass% for their suitability in the above mentioned applications.…”