METHOD OF ALLOYING STEEL BY MANGANESE IN OPEN- HEARTH FURNACES Russian patent published in 2003 - IPC

FIELD: ferrous metallurgy; method of making steel in open-hearth furnaces. SUBSTANCE: proposed method includes skimming of slag from furnace, production of new slag, addition of metal of manganese-containing material into melt in furnace; used as such material is low-phosphorous oxide manganese ore added to furnace at rate of 4-8 kg/t of steel ensuring reduction of temperature of metal at moment of addition or ore of no more than 20 C; after skimming of slag content of carbon in metal reaches magnitude exceeding high level by 0.10 to 0.25% at temperature of metal higher than liquidus temperature by 60-80 C. Amount of slag at basicity of 2/0-3.5 is maintained within 6- 8% of mass of metal; then, mixture of coke and ferrosilicon powder at ratio of 1:3 is added for deoxidation of slag at rate of 0.25-0.95 kg/t of steel. EFFECT: reduced consumption of ferroalloys; increased extraction of manganese; improved quality of steel. 1 tbl