A METHOD OF RAIL STEEL MAKING Russian patent published in 2008 - IPC C21C5/52 

FIELD: metallurgy.

SUBSTANCE: the method includes charging an electric steel furnace with metal scrap and liquid iron, melting, oxidization, melting steel in series, and tapping of melt, leaving slag and part of metal in the furnace. Then silicon containing materials at a ratio of 0.325-1.625 kg of silicon per tonne of metal left in the furnace or aluminium containing materials at a ratio of 0.425-2.16 kg of aluminium per tonne of metal left in the furnace are deposited to slag and part of metal left in the furnace after tapping of melt but before pouring of liquid iron at a ratio of 25-70% of a charge mass and metal scrap at a ratio of 30-75% of a charge mass. Oxidisation is carried out with gaseous oxygen at a rate of 80-120 m³/h per tonne of metal charge up to carbon content of 0.10-0.70% and a temperature not more, than 1700°C. As manganese containing alloys 0.60-0.75% of manganese and lime at a ratio of 3-12 kg/t of liquid steel are added to a ladle at tapping; further final melting up to required temperature and chemical composition is carried out on an aggregate ladle-furnace.

EFFECT: reduces duration of melt.