METHOD FOR ADDING COOLANT INTO TUNDISH

PURPOSE:To improve the solubility of a coolant and to maintain a uniform temp. of a molten steel after cooling by delineating a segmented pouring chamber into a tundish by a partition gate bored with a pouring hole and dissolving a coolant by the high-velocity flow formed by the pouring hole. CONSTITUTION:The tundish is partitioned by the partition gate 2 bored with the pouring hole 1 to provide the segmented pouring chamber. The size of the hole 1 is so determined that the molten steel flows at 20-40m/min flow rate in order to maximize the solubility of the coolant 6 and to improve the floating effect of inclusions. An undercut 3 is preliminarily provided to the gate 2 to prevent the stagnation of the molten steel in the segmented pouring chamber at the end of the casting. The molten steel poured through a pouring hole 5 of a nozzle 4 into the segmented pouring chamber is increased in the flow rate by the vena contracta around the coolant 6 added thereto just before the hole 1 to increase the dissolving speed of the coolant 6. The steel past the gate 2 diffuses to the uniform flow and is tapped from a tap hole 7 into a casting mold. The control of a wide temp. range is thereby made possible by the simple device.