RAIL STEEL MELTING METHOD Russian patent published in 2007 - IPC C21C5/52 C21C7/06 

FIELD: ferrous metallurgy, namely method for melting rail steel in electric furnace.

SUBSTANCE: method comprises steps of feeding to furnace metal scrap and melt cast iron; melting them; providing oxidation period; discharging melt while remaining slag and part of metal in furnace; adding to ladle (at discharging step) solid slag forming mixture; before discharging adding to furnace lime in quantity consisting of 1 - 3% of charge mass; pouring cast iron at temperature 1250 - 1360°C in quantity 40 - 70 % of charge mass onto slag and metal part remained in furnace; after pouring cast iron adding lime in quantity consisting 1 - 4% and metal scrap in quantity consisting 30 - 60% of charge mass. Oxidation is realized by means of oxygen gas at flow rate 8000 - 12000 m³/h till carbon content no les than 0.10% and temperature no more than 1680°C. At discharging, silico-manganese is added to ladle according to manganese calculated content corresponding to is lower limit content in ready steel. Then steel composition is finally controlled by temperature and chemical content in aggregate furnace-ladle.

EFFECT: lowered concentration of remaining elements, shortened period of melting process.

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