| 摘要 |
PURPOSE:To stabilize the operation of a converter and to diminish the variance of quality of produced steel by blowing a converter from an initial period of blowing to a middle period so that slag shows always over-slagging state and if necessary, performing the foaming regulating operation. CONSTITUTION:In the operating method of top-blown or upper bottom-blown converter, the converter is blown so that slag shows always over-slagging state from an initial period of blowing to a middle period by elevating the height of a lance and making soft blow of a top-blown oxygen jet. When the slopping is foreknown or detected with the method wherein the light of the inside of furnace is detected and the generation of the slopping is detected from the proportion occupied by the yellow color incorporated in the detected light, the foaming regulating operation is performed by means of charge of a slopping retardant or the like to stabilize the operation of the converter. Furthermore, preferably in a final period of the blowing, the decrease of Mn contained in the molten metal is prevented by making indication of the oxygen quantity contained in the slag or the slagging state and the enriching operation of Mn is performed to economize the additional quantity of alloy iron after the blowing. |
