METHOD OF TRIMMING SURFACE LAYER PORTION OF HOT SLAB AND PROCESS FOR PRODUCING HOT ROLLED STEEL

摘要

A method of trimming a surface layer portion of hot slab, comprising the step of cutting a thickness region of 1 mm or more from the skin of a slab just after casting over an area or the whole area of a surface layer portion of any one or two or more of the obverse face, reverse face and side face of hot slab produced by a continuous casting machine and cut into a given length by the use of a milling surface layer cutting apparatus consisting of an electrically operated rotary cutting tool with a multiplicity of cutting blades. By this method, there can be attained not only obtaining of a smooth trimmed surface but also highly efficient removal of any defects lying in the surface or under the skin of the hot slab without inviting any quality deterioration at the surface and surface layer portion of the hot slab.