Arrangement for controlling the flow out of a tundish
AssigneeSwerea Mefos AB
InventorsRalph Nystrom, Ulf Sjostrom
Life of this patent
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Abstract
In continuous casting of steel, the flow out of the tap hole (11) in the tundish (10) is controlled by a stopper rod that is rotatable so as to give the molten steel a swirling motion. This rotation reduces the risk of deposits in the tap hole and in the discharge tube (12). A non-rotatable sleeve around the stopper rod (16) extends through the slag layer (18) and into the molten steel (17). Protective gas is supplied to the gap between the stopper rod (16) and the sleeve (30) to prevent air from being drawn through the gap and into the molten steel.
Claims2
An arrangement for controlling flow of a tundish (10) that has a tap hole (11) for molten metal, said arrangement comprising an axially movable stopper rod (16) for controlling the flow out of the tap hole and a device (21, 22) for rotating the stopper rod;
- a sleeve (30) non-rotatably mounted around the stopper rod (16) by a mounting element attached to said sleeve;
- wherein said sleeve is arranged to extend through a slag layer (24) and down into molten metal (17);
- and means (31) provided for supplying protective gas to an annular gap between the stopper rod (16) and the sleeve (30) for preventing air from being drawn into the annular gap.
Dependencies are inferred from the claim text.