Discrete excitation coil producing seal at continuous casting machine

Abstract

An improved discrete excitation coil is provided in a continuous casting machine for generating an electromagnetic levitating and stabilizing force which acts upon the meniscus of the molten metal in a mold cavity of the machine at the region of an upper inlet to the cavity. The force counteracts the head pressure of the molten metal contained within a pouring tube which extends through the upper inlet from above the cavity and thereby providing a seal in an area of separation between the mold inlet and the pouring tube which prevents overflow of molten metal through the inlet. The excitation coil includes an outer electrical conductor which defines multiple electrical conductor turns disposed in series and being capable of carrying an electrical current of adequate density to generate the electromagnetic force. The coil also includes plural inner fluid channels which define fluid flow paths being surrounded by, and in contact with, the outer electrical conductor. The inner fluid channels are less in number than that of the multiple turns, and disposed in parallel to, but independent of, one another and in close proximity to the multiple turns. Coolant fluid circulated in the independent flow paths of the inner fluid channels can thereby provide sufficient cooling of the multiple turns to facilitate conduction therethrough of a high enough density electrical current to produce the required electromagnetic force.