| 摘要 |
<p>A liquid-cooled lance for blowing oxygen onto a bath of molten steel, has a tip (1) with at least one outlet from which a primary supply of oxygen is blown onto the bath, a central duct (2) for the supply of the primary oxygen surrounded by a double tube system (3,4) for supply and removal of cooling fluid, a plurality of secondary outlets (15) disposed around the lance in a conical widening of the lance axially spaced from the tip for blowing a secondary supply of oxygen and a plurality of secondary ducts (8, 9) extending along the lance for supply of the secondary oxygen to the secondary outlets. To obtain a high maximum possible scrap addition, and good control of final oxygen blowing temperature, there are at least eight of the secondary outlets (15) each having a diameter d. which satisfies the condition ds/l < 0.02 where 1 is the axial distance between the outlets for respectively the primary and secondary oxygen.</p> |
