To make appropriately controllable furnace condition.
This smelting furnace 1 has a jacket 3 for cooling a region in contact with molten metal M or a refractory in contact with the molten metal M in a furnace body 2; a refrigerant feeder 4 for feeding a refrigerant to the jacket 3; a supply side temperature measuring instrument 6 for measuring the temperature of the refrigerant supplied to the jacket 3; a discharge side temperature measuring instrument 7 for measuring the temperature of the refrigerant discharged from the jacket 3; an arithmetic unit 8; and a molten metal temperature measuring instrument 9 for measuring the temperature of the molten metal. The arithmetic unit 8 is constituted to receive the measured values from the supply side temperature measuring instrument 6 and the discharge side temperature measuring instrument 7, as signals and to obtain from these measured values the time series change of temperature difference between the refrigerant supplied to the jacket 3 and the refrigerant discharged from the jacket 3 or the time series change of a heat extraction amount in the jacket 3.
Tadashi Takahashi
Masakazu Aoyama
Akihiko Eguchi
Hideyuki Sugiura
Yasuhiko Murayama
Noriko Yanai