METHOD FOR REMOVING SCALE OF SURFACE LAYER OF HOT ROLLED SHEET

PURPOSE:To improve remarkably a descaling effect by regulating a rate of different speeds between opposing rolls to a specific value or more as well as regulating a rate of elongation to a specific value or less, in rolling a hot rolled sheet at the different speeds of rolls as a preceding process before a pickling or mechanical descaling process. CONSTITUTION:As a preceding process before a pickling or mechanical descaling process, a hot rolled sheet 1 is rolled by a high speed roll 2 and a low speed roll 3 which rotates at a lower peripheral speed than that of the roll 2. At that time, a rate of different speeds between the opposing rolls 2, 3 is regulated to >=1.2%, and a rate of elongation is regulated to lower than the rate of different speeds and preferably to