METHOD FOR OBTAINING STEEL FOR STEEL PIPES WITH EXCELLENT RESISTANCE IN ACID MEDIUM Russian patent published in 2011 - IPC C21C7/76 C21C5/28 

FIELD: metallurgy.

SUBSTANCE: method involves supply of steelmaking iron to the converter, oxygen blowing, tapping of molten steel to the ladle, supply of deoxidants, alloying and slag-forming elements to the ladle during molten steel tapping, and steel processing in the ladle. Steel with C, Mn, Si, P, S, Ti, Al, Ca, N and O content and optionally specified number of one or more of Cr, Ni, Cu, Mo, V, B and Nb is obtained. Steel inclusions have Ca, Al, O and S as the main components, and CaO content in inclusions is 30 to 80%, ratio of N in steel (ppm) to CaO content in inclusions (%) is 0.28 to 2.0, and CaS content in inclusions is 25% or less.

EFFECT: use of invention allows making high-strength steel for steel pipes with increased strength in hydrogen-sulphide medium and cleanliness.

5 cl, 3 dwg, 3 tbl