GB1003514A - Improvements in steel manufacture - Google Patents

Abstract

1,003,514. Burners; blowing lances. STEEL COMPANY OF WALES Ltd. Aug. 2, 1962 [May 10, 1961], No. 17053/61. Headings F4B and F4T. A lance for use in steel refining apparatus comprises a fuel supply conduit, coaxial within an oxygen supply conduit having an outwardly flared discharge orifice, said fuel supply conduit having an enlarged nose portion, with fuel discharge nozzles therein, forming a Venturi with the outwardly flared discharge orifice and setting up a low pressure zone at the centre of the fuel/oxygen mixture annulus. A fuel supply tube 15, Fig. 3, terminates at an enlarged nose portion which allows cooling water to pass down the tube 17 and back through the tube 19 and fuel to escape through the nozzles 33. The double-walled combustion oxygen conduit 28, which allows the circulation of cooling water forms a Venturi at the flared portion 29 with the enlarged nose portion and is surrounded by a further water-cooled, flared tube which supplies a stream of oxygen, preheated by the inner flame 47, to the surface of the melt, although this outer tube is omitted in three other embodiments. In the first, Fig. 1 (not shown), the flame end of the nose portion is flat, in the second, Fig. 2 (not shown), it is curved as shown in Fig. 3, and in the third, Fig. 5 (not shown), it is frusto-conical with channels in the outer side of the fuel supply conduit. In another embodiment, Fig. 4, an oxygen conduit 49 is surrounded by a fuel supply conduit 50, the fuel passing through the orifices 51 to mix with oxygen and burn to form a flame 48 which preheats oxygen passing through the watercooled flared conduit 12. Specification 1,003,515 is referred to.