| 摘要 |
PURPOSE:To constrain the formation of an oxide on the surface of a molten metal and to obtain a good ingot by introducing an inert gas to the inner part of a cover member by coating the upper part and side part of a molten metal column by the cover member. CONSTITUTION:A cover body 30 as a cover member is arranged so as to close the upper part opening of a casting hole 25 for the upper face of a cooling water jacket 24, i.e., so as to cover the whole upper face body of a molten metal column 16 on a mold 18. A nozzle 12 feeding a molten metal is arranged by penetrating the cover body 30 and a gas feeding port 32 is provided on the cover body 30 by penetrating through a wall part. When an inert gas is fed into the cover body 30 from the gas feeding port 32, the space in which the free surface of the molten metal column 16 is exposed is held under inert gas atm. The generation of an oxide film on the surface of the molten metal column 16 and its growth are thus prevented effectively and the surface of the ingot 20 to be obtd. is improved. |
