EASY TAPPING AND DEGASSING DEVICE FOR BOTTOM TAPPING FROM FURNACE

摘要

PURPOSE:To remove N2 from a molten steel and to produce a low-nitrogen steel with a simple device by moving a ladle for the molten steel to the underside of an electric furnace having a tap hole in the furnace bottom, airtightly connecting the ladle and tapping part with a sealing cover in the tapping part of the electric furnace and tapping the molten steel from the electric furnace after reducing the pressure in the ladle. CONSTITUTION:The ladle 8 imposed on a ladle carriage 4 is moved to the underside of the electric furnace for steel making having a tapping device 2 of a slide gate type, etc. in the bottom 1. The ladle 8 is raised by the operation of a piston 7a of a fluid pressure cylinder 7 installed to a trunnion stand 6 of the ladle carriage 4 to hermetically connect a truncated circular cone-shaped cap 12 hermetically attached to the aperture in the upper part of the ladle 8 to a sealing cover 3 of the device 2. After the pressure in the ladle 8 is reduced to about 1 Torr by a discharge duct 13, the slide gate 2 is opened to drop the molten steel in the electric furnace in the form of a jet 14 into the ladle 8 and the gaseous N2 contained in the molten steel is removed during such process.