| 摘要 |
PROBLEM TO BE SOLVED: To produce a hot rolled steel sheet having surface quality in which both of scaled defects such as red scales and defect caused by faults in sheet passing such as flaws caused by drawing or rolling or the like are not present. SOLUTION: In a hot rolling of a steel sheet contg. Si, a slab is heated to 1000 top 1173 deg.C surface temp. and is subjected to rough rolling to obtain a roughened bar. Next, this roughened bar is heated to Tr to 1173 deg.C surface temp., is thereafter subjected to descaling by high pressure water under >=100kg/cm<2> discharge pressure and is subsequently subjected to finish rolling, where Tr is the temp. given by the equation of Tr=1050×t<-0.1> in accordance with the objective sheet thickness (mm).
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