CONVERTER STEELMAKING METHOD FOR CHARGING MOLTEN IRON OBTD. BY MELTING COLD PIG IRON OR THE LIKE

摘要

PURPOSE: To enable stable oxygen blow-refining with a small amt. of impurities because a molten metal having no remaining unmelted cold pig iron, etc., can be charged into a converter. ;CONSTITUTION: Measured value T₁ of a molten metal temp. before charging into the converter 2, time t₁ from empty converter to charging of iron surce of the cold pig iron, etc., and measured value TO of the molten iron temp. tapped into a molten iron ladle 3b preceding the empty molten iron ladle 3a, are obtd. From the relation among these actual meassured values, the time set value t₃ till receiving the molten iron into this empty molten iron ladle 3a, the set value W of a received molten iron quantity and the time set value t₄ from receiving the molten iron till charging this into the converter, the molten iron quantity W capable of melting iron source of the cold pig iron, etc., is predicted. This predicted iron source quantity W of cold pig iron, etc., is beforehand set to the empty molten iron ladle and the set molten iron quantity is received to this molten iron ladle 3a and the iron source is melted, and after executing pretreatment of desulfurization, dephosphorization, etc., the molten iron is charged into the converter 2 while holding this at the temp. of ≥1230°C, the oxygen blow-refining is executed.;COPYRIGHT: (C)1993,JPO&Japio