| 摘要 |
<p>PURPOSE:To shorten a steel making stage and to improve thermal efficiency and the quality of a steel by evacuating a hermetically maintained melting furnace and hermetic vessel hermetically connected to the tap hole thereof and restoring the pressure in the melting furnace by an inert gas then dropping a molten metal from the tap hole into the hermetic vessel. CONSTITUTION:A material to be melted is charged into the melting furnace 2 and after the furnace 2 is hermetically closed, a melting stage is started to make component adjustment. The inside of the furnace 2 is evacuated to a vacuum by an evacuating means 17 to start a vacuum refining stage upon completion of said adjustment. The inside of th hermetic vessel 14 hermetically connected to the tap hole 6 of the furnace 2 is evacuated to a vacuum by the means 17. The inert gas is sealed into the furnace 2 including an enclosure 10 by a pressure restoring means 24. The entire part of the furnace 2 is titled to the vessel 14 side at the point of the time when the vessel 14 attains a prescribed degree of vacuum. The molten metal 27 is dropped into a ladle 15 which is the vessel 14 from a sprue 6 when a stop valve 29 of the sprue 6 is opened.</p> |
