METHOD FOR MANUFACTURING HOT ROLLED STEEL SHEET INCLUDING HIGH CARBON CONTENTS WITH EXCELLENT SURFACE QUALITY USING MINIMILL PROCESS

摘要

PURPOSE: A method for manufacturing high-carbon hot rolled steel strips with excellent surface quality by using a mini mill process is provided to reduce line scale on a base metal remaining in a raw material by optimizing roughing mill temperature and descaling conditions by using a descaler in front of a roughing mill. CONSTITUTION: A method for manufacturing high-carbon hot rolled steel strips with excellent surface quality by using a mini mill process is as follows. A molten steel is composed of C 0.2 to 1.3wt.%, Mn 0.2 to 2.0wt.%, Si lower than 0.5wt.%, residual Fe, and inevitable impurities. The molten steel is continuously casted into 30 to 150mm thickness of a thin slab(a). The thin slab is descaled and roughly rolled in 850 to 1150C temperature in the input side of a roughing mill(20). The hot rolled strip(b) is finally rolled and coiled after cooled in a ROT(Run-Out Table)(60).