COLD-RESISTANT WELDED STEEL Russian patent published in 2008 - IPC C22C38/44 C22C38/12 

FIELD: metallurgy.

SUBSTANCE: cold-resistant steel is used for manufacturing of welded pipe fitting, operating in low temperature conditions. Steel contains carbon, silicon, manganese, chrome, nickel, molybdenum, aluminum, cerium, calcium, sulphur, phosphorus and iron, at following ratio, wt %: carbon 0.08-0.12, silicon 0.40-0.80, manganese 0.90-1.20, chrome 0.01-0.50, nickel 0.30-0.90, molybdenum 0.20-0.35, aluminum 0.01-0.05, cerium 0.010-0.020, calcium 0.005-0.05, sulphur is not more than 0.020, phosphorus is not more than 0.020, iron is the rest. Carbon equivalent value, equal [C]equiv=C+Mn/6+(Cr+Mo)/5+Ni/15+P/2, do not exceed 0.430.

EFFECT: improving of weldability at saving of strength and cold resistance high level.

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