| 摘要 |
PURPOSE:To stably execute decarbonized-refining in simple process and to restrain wear of refractory by adding solid nucleus generating material near a fire point by top blowing in a converter when carbon content in molten steel is become to lower than the specific value. CONSTITUTION:The ordinary converter refining is executed by blowing oxygen through a lance from upper part while blowing oxygen or oxygen-contained gas from tuyere arranged at the furnace bottom of the converter. When the carbon content [C] in the molten steel becomes <=0.3% by this refining, the decarbonization by the oxygen supplying from the top blowing lance and the bottom blowing tuyere, a begin to slow down, and T.Fe in slag is rapidly increased. In a partial term or over whole term from <=0.3% [C], in which the decarbonization begins to slowdown, to blowing-finish, powdery material of the solid nucleus generating material (CaCO3, etc.) is added by the top blowing oxygen in the converter near to the fire point. Then, blowing quantity of the powdery material is to be about 1.5-15kg/T and its blowing rate about 1.0-40kg/T and its grain size about <=600mu.
|
