METHOD FOR GRINDING BOTH-SIDE EDGES OF ELECTROPLATED STEEL SHEET AND ELECTROPLATED STEEL SHEET HAVING GROUND BOTH-SIDE EDGES

PURPOSE:To obviate the necessity of edge trimming, to improve the yield of a plated steel sheet, and to prevent the occurrence of flaw at the time of press working by grinding the overcoating at the edge of a plated steel sheet by using a brush roll. CONSTITUTION:An integral brush roll, in which an upper edge brush 3 and a lower edge brush 4 rotate in directions reverse to each other, is pressed against the edge of an electroplated steel sheet, by which a dendritic plating metal depositing and adhering on and to the edge of the steel sheet is ground away from the upper and the lower surface simultaneously. An inclination of 10 to 40 degrees is provided to the integral brush roll in a vertical direction of the steel sheet, and the brush roll is pressed against the sheet edge so that the sheet edge is held between the upper and the lower edge brushes 3, 4 by 2 to 10mm. This brush roll is rotated at prescribed number of revolutions. At this time, a pass line position control device 7 is installed on the front side of the brush roll, and the position is held in the prescribed position so that the edge of the steel sheet is always in the central part between the upper and the lower surface of the brush roll. By this grinding, the plated steel plate having nearly equal plating thickness over the whole surface of the steel sheet can be obtained.