| 摘要 |
PURPOSE:To improve corrosion resistance in a weld zone as well as sour resistance by limiting the content of Ni, N, and further Nb in austenitic stainless steel to a specific range. CONSTITUTION:As material for apparatus used in the development drilling of sour oil and sour gas containing acid gas such as gaseous H2S, CO2, or the like, the chemical composition of the austenitic stainless steel containing, by weight, 0.05-0.10% C 0.10-30% Si, 2.0-4.0% Mn, 15-17% Cr, 6-11% Ni, 2-4% Mo, 0.05-0.25% V, and 0.05-0.18% N is regulated so that general expression (1) is satisfied when (Cr equivalent)=%Cr+%Mo+1.5%Si+0.5%Nb and (Ni equivalent)=%Ni=30%C+30%N+0.5%Mn. The high-strength austenitic stainless steel for welding construction combining corrosion resistance with yield strength and excelling in sour resistance can be obtained.
|
