METHOD OF MAKING STEEL Russian patent published in 2006 - IPC C21C5/28 

FIELD: ferrous metallurgy; making steel in oxygen top-blown converters.

SUBSTANCE: liquid metal at increased fraction of scrap in charge is molten in oxygen converter. Temperature is decreased by 3-5°C per ton of increase of consumption of scrap and flow rate of oxygen is reduced by 0.85-0.97 m³/t at rate of temperature decrease of 10°C. Minimum temperature of metal it its decrease is not below 1610°C. At tapping molten metal into ladle, ferruginous dolomite is added in way of blowing and molten metal is tapped to ladle which is heated preliminarily. During tapping, ferroalloys and aluminum, as well as lime and fluorspar are delivered to molten metal. Consumption of lime is 5-8 kg/t and that of fluorspar is 1.3-2 kg/t. 40-60% of lime and fluorspar is fed to surface of metal in ladle. After tapping, molten metal is subjected to electrical heating in ladle to temperature required for off-furnace treatment followed by continuous casting.

EFFECT: reduction of melting time; reduced consumption of oxygen, fuel and slag-forming agents; cut costs of steel; enhanced stability of lining.

3 cl, 3 tbl