| 摘要 |
<p>1,064,737. Metal melting furnaces. SUNBEAM ENGINEERING CORPORATION. Dec. 16, 1963 [Dec. 21, 1962; Dec. 4, 1963], No. 49628/63. Heading F4B. Steel is produced in an uncompartmented furnace having two hearths, the gases produced by blowing the melt in one hearth with oxygen being passed over the other hearth to preheat a charge of scrap. The hearths 18, 20, which may replace the single hearth of an existing furnace, contain a melt at least four feet deep, and have separate covers (58, 60, Fig. 3, not shown) forming a two-part furnace roof. Each cover carries a retractable lance for the supply of oxygen and/or fuel for refining a charge, and tilted lances through which air or oxygen is supplied to burn the waste gases from the refining hearth and direct them on to the scrap charge for preheating. The end passages 42, 44 of the furnace are connected to the stack through a damper so that the flue remote from the refining hearth is operative and the gases flow over the preheating hearth. Each cover has two doors closing the charging opening 70 for scrap, and a trough 84 delivering molten metal tangentially to the hearth, Fig. 2. Each tap hearth has a central tap-hole 88 and a shoot 90. A number of cover members may be provided so that they can be repaired without interrupting production. A charging apparatus 13 running on rails 14, Fig. 1, comprises two scrap boxes 140, 138 and a retractable shoot 136 which enters the charging hole to each hearth. The height of the assembly may be adjusted by hydraulic rams (144, Fig. 7, not shown) and the scrap-boxes 140, 138 are tilted about their front ends by rams. A gate 154 in the shoot 136 directs the scrap from either box into the furnace. In a modification, a number of scrap bins are mounted on a turntable above the retractable shoot. Each bin is moved in turn above the shoot, and its bottom opened to charge the hearth.</p> |
