Abstract: To permit placement of a stopper element, preferably including a cylindrical alignment plug (13) accurately with respect to an outflow pipe (3, 3', 3") of a metallurgical vessel adapted to contain a melt, an operating rod (5) vertically projecting from the stopper (6) is surrounded by a refractory sleeve (10), and secured to a support arm (23), which support arm is vertically movable and capable of transmitting rotation to the operating rod, the operating rod is connected to the support arm by a coupling link (48) which extends radially from the operating rod and is clamped by a clamping connection (46) to the support arm. The clamping connection (46) permits longitudinal adjustment of the upper end portion of the operating rod (5) as well as angular adjustment with respect to the support arm.

Abstract: A stopper (6), secured to the lower end of a stopper rod, carries a plug (13) having a radial throttle aperture (14) above which a frustoconical shut-off surface (16) is located. The frustoconical surface fits against a valve seat surface 18 of an outlet tube (3) from a vessel, to form a first seal. A further seal is provided by an annular surface (19) of the plug (13) engaging in the outlet passage. The stopper (6) is rotatable so that the direction of flow of the molten metal from the vessel (1) and, passing through the stopper--when raised--can be influenced, if desired continuously during flow of the melt. This provides flow control and a safe shutoff of metal flow. The formation of vortices in the molten metal is largely prevented, thus avoiding the carrying along of slag.