| 摘要 |
<p>In a continuous steelmaking process, a molten metal bath is maintained within a rotary furnace heated by oxy-fuel burners at the charge and discharge ends. Metallic iron charge material such as iron and steel scrap or sponge iron is preheated primarily by heat transferred from the furnace exhaust gases, on an enclosed recuperative conveyor before being introduced through the charge end opening. Molten metal is withdrawn through a siphon tube submerged in the bath through the furnace discharge end opening into a vacuum chamber which is part of an integral vacuum chamber-tundish combination incorporating a molten metal column under vacuum in one leg and a molten steel tundish casting pool under atmospheric pressure as the other leg, connected via a submerged channel. As steel is cast out of the tundish through a submerged nozzle, it is replenished by way of the column from vacuum-induced flow through the siphon tube, metal surface levels in column and tundish remaining substantially constant once casting has been established. Several means are provided for regulating withdrawal and casting rate, including the use of slide-gate valves and varying the vacuum pressure.</p> |
