METHOD OF MELTING RAIL STEEL OF HIGH PURITY RELATIVE TO NONMETALLIC INCLUSIONS IN ELECTRIC ARC STEEL MELTING FURNACE Russian patent published in 2003 - IPC

FIELD: ferrous metallurgy, particularly, production of rail steel; applicable, mainly, in melting steel for railroad rails in electric arc steel melting furnaces. SUBSTANCE: method includes charging of iron charge during iron ore charging in amount of 0.5-1.0 kg of iron charge per ton of iron ore; melting of iron charge, oxidation. After oxidizing slag flushing, at end of oxidation period, introduced into furnace is mixture containing fluorospar and lime in ratio of (0.1-0.5):(1.5-2.5) in amount of 1.5-3.5 wt.% of steel. During reduction period, slag is deoxidized in furnace with mixture of coke powder, crushed ferrosilicon, granulated aluminum which are introduced in amount of 0.80-1.20 kg of each mixture component per ton of steel. Added during tapping of steel into ladle is mixture of lime, fluorospar, silicocalcium and aluminum pigs in the following ratio (1.2-1.5)):(0.3-0.4): (0.65-0.85): (0.010-0.020), respectively. Mixture consumption is 14-20 kg/t of steel. EFFECT: reduced amounts of impurities in the form of nonmetallic inclusions, increased mechanical properties and impact strength of rail steel. 3 tbl