PROCEDURE FOR MELTING RAIL STEEL Russian patent published in 2010 - IPC C21C5/52 C21C7/76 

FIELD: metallurgy.

SUBSTANCE: procedure consists in supply of metal scrap and liquid iron as metal charge into furnace, in melting, in oxidising, in melting steel in batches, in tapping melt and leaving part of metal in furnace, in adding solid slag forming mixture, deoxidisers and alloying agents into ladle during tapping and in heat finishing steel by temperature and chemical composition at ladle-furnace aggregate. Liquid iron with contents of silicon not more, than 0.45% and phosphorus not more, than 0.09% at amount of 25-75% of charge weight is poured on slag and part of metal left in the furnace. Metal scrap at amount of 15-35% of charge weight, composite semi-finished product at amount of 10-40% of charge weight and lime at amount of 3.0-4.3% of charge weight are charged into furnace. During melt and oxidising there are carried out blow with gaseous oxygen at consumption rate 6000-12000 m³/h, addition of lime at amount of 0.4-1.3% of charge weight in portions by 50-200 kg and injection of carbon containing powder at rate of 15-100 kg/min.

EFFECT: upgraded quality of steel, reduced consumption of lime and electric power.