PURPOSE: To automatically suck the molten metal in a metal furnace by a molten metal sucking pipe by setting the pressure in a molten metal tank to the pressure in the furnace when the molten metal is sucked by making use of the pressurized gas when the molten metal is fed.

CONSTITUTION: An upper part of a molten metal tank 2 is sealed, a pumping pipe 5 of the gas is connected to an upper wall 2a, and an automatic valve 6 is interposed to the pumping pipe 5. The automatic valve 6 is used for feeding and discharging the pressurized gas, and when the pressurized gas is fed, the molten metal is fed. When the pressurized gas is discharged, the molten metal is introduced into the molten metal tank That means, the automatic valve 6 is opened, and the pressurized gas is discharged outside, and if the pressure inside the molten metal tank 2 is equalized to the atmospheric pressure, the molten metal flows into the molten metal tank 2 through a molten metal tube 4 and a molten metal feeding pipe 3 as indicated by the arrows 7, 8 due to the pressure of the molten metal in the furnace. When the pressurized gas is fed into the molten metal tank 2 as indicated by the arrow 10, the molten metal flows in the molten metal feeding tube 3 as indicated by the arrows 12, 13, 14 and is carried to the prescribed place.