WELDED HIGH-STRENGTH STEEL TO MANUFACTURE SEAMLESS CORROSION-RESISTANT PIPES AND CONTAINERS Russian patent published in 1998 - IPC

FIELD: steel making. SUBSTANCE: invention relates to manufacturing seamless steel pipes or flat products (stripes or sheet) for manufacturing pipes or containers appropriate to supply, transportation, or processing gaseous or liquid hydrocarbons containing carbon dioxide and water and, in particular instances, small concentration of hydrogen sulfide. Manufactured products are resistant against corrosion cracking and also have good weldability and elongation 0.2% with effort at least 450 N/sq.m. To achieve it, nickel-containing steel is used composed, wt.-%: carbon, 0.015; silicon, 0.15-0.50; molybdenum, maximum 2.0%; phosphorus, maximum 0.02; sulfur, maximum 0.003; chromium, 12.0-13.8; nitrogen, 0.002-0.02; niobium, 0.01-0.05; iron and common admixtures, the balance. According to invention, content of nickel should be limited by 0.25%, minimum manganese content 1.0%, carbon content no higher than 0.035%, and, as added alloying component, 0.01-1.2% molybdenum should be contained. EFFECT: improved performance characteristics of steel products. 9 cl, 2 dwg, 3 tbl