METHOD FOR REMOVING DEPOSIT ON SURFACE OF STEEL STRIP HEAT-TREATED IN LEAD BATH, AND BRUSHING DEVICE

PROBLEM TO BE SOLVED: To efficiently remove foreign matters deposited on a surface of a steel strip subjected to the isothermal treatment in a molten lead bath. SOLUTION: In the isothermal treatment of continuously passing a steel strip in an isothermal treatment furnace in which a heating zone, a quenching zone having a molten lead bath and a holding zone which is kept at the atmospheric temperature substantially equal to the bath temperature of the molten lead bath are continuously disposed in this order, a brush (13) formed of thin metal wires is pressed against and brought into slidable contact with both upper and lower sides of the steel strip passing through the holding zone under an elastically pressed state. The temperature of the steel strip passing through the holding zone is high, and the coagulation force of deposited lead-based foreign matters on the surface of the steel strip is relatively small. Therefore, when the brush is brought into slidable contact with the surface of the steel strip while keeping a pressed state of the brush, the elastic repulsive force of the thin metal wires works as a wiping force to separate the deposited lead-based foreign matters from the surface of the steel strip, and the deposited lead-based foreign matters can be efficiently peeled and removed. COPYRIGHT: (C)2005,JPO&NCIPI