METHOD FOR REPAIRING CONVERTER LINING Russian patent published in 1999 - IPC

FIELD: metallurgy, namely, process for slugging refractory lining of converter and applying onto it lining slag for increasing lining strength. SUBSTANCE: method comprises steps of blowing melt in converter by oxygen from upper side through tuyere, supplying slag-forming material to converter including dolomite and lime at blowing, pouring melt from converter into steel pouring ladle at remaining slag in converter. During melting previous before repairing magnesia slag is fed to converter until achieving content of MgO equal to 15-12% due to feeding dolomite at specific flowrate 20-50 kg/t of melt. Then melt is discharged and 90-98% of formed slag is remained in converter, tuyere is immersed to converter and slag is blown by neutral gas at flowrate consisting 0.4-1.2 of oxygen flowrate of previous melting for 0.5-30 min in order to apply lining slag on converter lining. At blowing slag by neutral gas tuyere is driven to reciprocation motion along converter by distance equal to 15-35 calibers of tuyere nozzles at rate 0.05-0.5 m/s; setting minimum distance of tuyere until slag level at killed state in range of 5-20 calibers of tuyere nozzles. Dolomite mixed with lime is fed to converter. It is possible to feed dolomite in addition with flowrate 1-1.5 kg/t of melt at process of previous melting before blowing slag by neutral gas. EFFECT: enhanced efficiency, high quality of applying lining slag on converter lining. 4 cl, 1 tbl, 1 ex