PROCEDURE FOR MELTING STEEL IN ARC STEEL MELTING FURNACE WITH INCREASED CONSUMPTION OF LIQUID IRON Russian patent published in 2011 - IPC C21C5/52 

FIELD: metallurgy.

SUBSTANCE: procedure consists in loading metal scrap and liquid iron as metal charge, in melting, in adding lime, in oxidation period, and in melt tapping. Steel is melted in two stages: during the first stage metal scrap is loaded at amount of 10…12 % of weight of metal charge and lime at amount of 0.7…1.0 % of weight of metal charge. Liquid iron is poured at amount of 38…40 % of weight of metal charge by means of a charging launder at rate 4…5 t/min and at consumption of electric power 70…85 kWt*h/t of metal charge. Further, after consumption of electric power of 200…210 kWt*h/t of metal charge current is switched off. A bath is blown with oxygen to oxidation of metal not less, than 600 ppm in 1.5… in 2.0 min after turning current on. During blowing there is added lime in portions of 0.5…1.0 t with consumption of 1.5…2.0 % of weight of metal charge. The first melt is tapped into a steel teeming ladle. At the second stage the second melt is melted according to the same process. When it is ready, the steel teeming ladle with the first melt is repositioned for tapping.

EFFECT: raised efficiency of steel melting.

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