METHOD OF STEEL MELTING IN CONVERTER Russian patent published in 1999 - IPC

FIELD: metallurgy, particularly, steel melting in converter. SUBSTANCE: method includes charging of scrap into converter, pouring of pig iron into converter, top blowing of melt with oxygen through multihole lance, variation of oxygen consumption, supplying of slag-forming materials to converter and determination of chemical composition of pig iron and melt. During the first period of blowing, covering 0.1-0.5 total blowing time, oxygen consumption is determined by relationship Q₁ = K₁.Si.Mn.G, where Q₁ is oxygen consumption during the first period of blowing, cu.m/t.min; Si is silicon fraction of total mass in pig iron, %; Mn is manganese fraction in pig iron, %; G is weight of poured pig iron into converter, t; K₁ is empirical coefficient considering physico-chemical regularities of melt decarburization equalling 0.07-2.5 cu. m/%•%•min•t². Silicon fraction in pig iron is set within 0.25-1.2 wt. %; manganese fraction within 0.05-0.3 wt.%; pig iron fraction in iron charge within 0.7-0.95 of total amount of iron charge. Upon expiration of indicated time, oxygen consumption Q₂ is increased to value of K₂•Q₁, where K₂- is empirical coefficient characterizing physico-chemical regularities of melt decarburization equalling 1.1-2.0, dimensionless. EFFECT: reduced amount of melt carry-over from converter and consumption of iron charge and oxygen. 1 tbl