| 摘要 |
<p>PURPOSE:To attain the enhancement of productivity of steel and the saving of energy by making the best of the advantage of an oxygen-enriched operation by a method in which carbon content of molten steel is once reduced to a low level and again raised. CONSTITUTION:A raw material, e.g., scraps, etc., is charged into an arc furnace 1 and melted by arc, and oxygen gas is blown into the furnace through a lance pipe 6 in the molding and oxidizing periods to make a steel with a carbon content of 0.20% or less. While making such arc heating and oxygen blowing, molten pig iron containing at least approx. 2.0% or less carbon is charged in a given proportion from a container 7 into the furnace 1, whereupon slag 4 upheaves. The preferred amount of the molten pig iron to be charged at the final stage is approx. 10-50%, by which the amount of carbon to be supplied from the molten pig iron is regulated to be approx. 0.2-2.0kg/min per to of the molten steel. Thus, the increase in the amount of slag and the wearing of the wall of the furnace can be suppressed.</p> |
