| 摘要 |
<p>A bath of chromium steel is refined using tuyeres located below the level of the bath, each tuyere consisting of three concentric tubes, the object being to obtain a very low carbon content without excessive loss of Cr to the slag; the novelty is that steam and a non-oxidising gas are blown simultaneously through the two inner tubes of the tuyeres while a fluid protecting the refractories is blown through the outer annulus, the amt. of steam and the non-oxidising gas being controlled so the carbon content is lowered without excessive loss of Cr and with simultaneous regulation of the bath temp. The non-oxidising gas may be H2, N2, Ar or He; when N2 is used, the flow is pref. sufficient to obtain a chromium steel contg. 0.1-0.25% nitrogen.</p> |
