PURPOSE: To perform simultaneously blowing of powder during degassing treatment by installing a valve to the blow port in the bottom of a vessel, heating electrically the valve to melt the solidified metal near the valve then blowing the powder together with gas into the molten metal.
CONSTITUTION: Powder is blown together with gas into a molten steel 1 while the molten steel is subjected to a vacuum degassing treatment in the upper part in a vessel 2 such as a ladle or the like. A gate 10 in the bottom is closed and electricity is conducted from upper and lower electrodes 11, 12 to heat and melt the solidified steel in a blow port (nozzle) 4 in the stage of starting such powder blowing. On the other hand, the pressure of a carrier gas for powder blowing is maintained under the head (static pressure) of the molten steel or above and the gate 10 is opened to blow the powder 5 through a piping 8. There are practically no obstructing materials on the surface of the molten steel according to such method and therefore the degassing treatment of the steel 1 is simultaneously accomplished without interference even during the blowing operation.
KOBAYASHI ISAO
TAKEMURA YOUZOU
