Abstract: A repairing method using a lance for repairing an oven wall surface of a coke oven comprises the steps of arranging a distance sensor at a top end of the lance, quantitatively measuring a depth of a worn or a damaged area by the distance sensor, and blowing a repairing material from a repairing nozzle to the worn area in accordance with a measurement result to thereby repair the worn area. The lance used in this repairing method has a multistage structure having a polygonal cross section and is extendable. With this structure, the oven wall surface can be scanned in a linear fashion or along a plane. If the top end of the lance is movable in accordance with a basic motion pattern and/or a travelling pattern, it is possible to readily repair a repair range having a complicated shape.

Abstract: In an electromagnetic stirring method, one or two electromagnetic inductors are provided to define an internal space therein or therebetween, a plurality of pairs of opposed magentic poles are provided on the inner side walls of the electromagnetic inductors defining the space, and the polarities of the magnetic poles are sequentially rotated by one or two power supply devices to generate a plurality of rotating flows of a molten metal as seen in a cross section thereof as it passes through the internal space defined by the electromagnetic inductors.