PRODUCTION OF HOT-DIPCOATED STEEL SHEET

PURPOSE:To produce the hot-dip coated steel sheet excellent in corrosion resistance and chemical convertibility with high productivity by a simple process by subjecting a hot rolled steel strip to cold rolling, subjecting the surface to electric arc treatment in a vacuum chamber to clean the surface of the steel strip, and thereafter, subjecting the surface to hot dipping treatment. CONSTITUTION:A slub of low carbon aluminum-killed steel, dead soft steel or dead soft alloy steel, etc., is subjected to hot rolling, and thereafter, oxide scale on the surface is removed by a deoxidizing treatment, and also, by applying rust preventing oil and executing cold rolling, a steel strip is formed. This cold rolled steel strip 1 is supplied into a vacuum chamber 3 through a differential pressure seal chamber 2 and set as the cathode through a conductive roll 4, an electric arc 6 is discharged between the cathode and the opposed anode, and the surface is cleaned completely by removing rust preventing oil and rolling oil on the surface of the cold rolled steel sheet 1, thereafter the surface is subjected to hot dipping through a reducing/annealing process. In such a way, a hot-dip coated steel strip excellent in surface quality can be produced by a simple process.