METHOD OF STEEL LADLE TREATMENT Russian patent published in 2001 - IPC

FIELD: ferrous metallurgy, more specifically treatment of steel in ladle with use of circulation degassing. SUBSTANCE: method includes supply of steel into ladle; steel circulation degassing with continuous passing of steel through vacuum chamber having suction and discharge branch pipes; supply of transporting gas to suction branch pipe and supply of oxygen to vacuum chamber through water-cooled tuyere installed to above vacuum chamber bottom. Tuyere is installed at angle to bottom surface at height above bottom surface equaling H=K x Q x q x t/(C1-C2), where H is height of tuyere position above bottom of vacuum chamber, m; W is oxygen flow rate through tuyere, cu. m/min. t of steel; q is transporting gas flow rate in suction branch pipe of vacuum chamber, cu.m/h;t is tell temperature in ladle before treatment, C; Cl is carbon content in steel before ladle treatment, wt. %; C2 is required content of carbon in steel after treatment, wt. %; K is empirical coefficient equaling (15-45) 10^-6, min.t.h.%/m⁵ C. Angle of tuyere inclinations within 45-75 deg. Tuyere longitudinal axis is located at distance from bottom center equaling 0.5- 0.9 of bottom radius. EFFECT: higher efficiency of steel decarbonization in process of its treatment and higher degree of heat utilization in steel degassing. 2 dwg, 1 tbl, 1 ex