PURPOSE: To decrease the consumption at the forward end of blow pipe tuyeres in refining a Cr-contg. bath under blowing of gaseous flow through the tuyere by executing at least the stage of reducing Cr subjected to the oxidation refining by blowing of gaseous O2 by using gaseous CO or a gaseous mixture of CO and an inert gas.
CONSTITUTION: The Cr-contg. bath melted in a melting furnace or converter is subjected to refining under blowing of the gaseous flow through a tuyere opening under the bath surface. At least the stage of reducing Cr oxidized with the oxidation refining using blowing of gaseous O2 is progressed by using gaseous CO or a gaseous mixture of ≥5% gaseous Co and the balance an inert gas as the gaseous flow. Double-ply pipes are used for the tuyere, and the gaseous CO or the gaseous mixture of ≥5% gaseous CO and the balance an inert gas is blown into the Cr-contg. bath through the clearance between the inside and outside pipes of said tuyere.
HARADA NOBUO
NAKAMURA HIDEO
SAKURATANI TOSHIKAZU
FUJII TETSUYA
EMI TOSHIHIKO
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