Abstract: The level of molten metal in the mold of a continuous metal caster is controlled by regulating the open area of a variable outlet nozzle in a tundish. The level of molten metal is monitored, and the extent and direction of any detected deviation is signalled to a computer which also receives a signal indicating the position of a movable valve member in the tundish outlet nozzle and a separate signal representing the rate of withdrawal of the cast metal from the mold. The computer determines the extent of movement of the valve member to correct the liquid metal level in the mold and controls actuation of a hydraulic drive system to move the valve member to reduce the position error to zero. The velocity of movement of the valve member is measured and fed back to the computer, with the velocity measurement being utilized by the computer to control the hydraulic system and more accurately position the movable valve member.