| 摘要 |
PURPOSE:To improve the product quality and to reduce the cost by bringing a part of a hot rolled steel strip in a specific range inside from an edge end in the width direction of the strip to be thicker than an average sheet thickness by a prescribed amount and then restraining variations in sheet thickness in the longitudinal direction within a specific range. CONSTITUTION:Vertical rolls 2 are installed in the outlet side of a final finishing stand 1 for hot rolling to perform light edging; or respective opposite roll edges of a couple of upper and lower work rolls 6 in the final stand of the finishing mill are chamfered to roll down the part about 5 mm inside from a coil edge. Thus, a sheet thickness of a part not exceeding 8 mm inside from a side edge end in the width direction of a steel strip is made thicker than an average thickness in the width direction by 20-50mum and variations in a longitudinal thickness are restrained to be <=40mum. Strip surfaces are prevented from air invasion by a thickness increase in the edge parts. Therefore, scale adhesion gets better and the product quality is improved. The cost is also reduced because the working is simple.
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