METHOD OF MANUFACTURING LOW SULFUR AND LOW CARBON STEEL BY ELECTRIC ARC FURNACE-VACUUM TANK DEGASSING METHOD

摘要

PURPOSE: A method of manufacturing the low sulfur and the low carbon steel by a gas removal method of an electric arc furnace - vacuum tank is provided to remove carbon of steel and sulfur using a vacuum tank degassing after charging the ladle into a vacum part. CONSTITUTION: A method of manufacturing the low sulfur and the low carbon steel by an electric arc furnace - vacuum tank degassincomprises : a step of controlling the content of FeO+MnO in a slag(18) of a ladle(12) to come to 6-20wt.% ; a step of operating degassing for making a part(16a) generated by a mixing layer of a gas and molten steel being(16) being 35-80% of a horizontal section of a ladle(12) ; a step of operating desulfur by controlling a component of a slag(18) so that FeO+MnO density of a slag(18) is less than 1.5wt.%, and a ratio of CaO/Al2O3 is 1.2-2.5 by projecting and stirring the deoxidizer into a molten steel(16) and quicklime into a slag(18).