Maximum draft schedules of thin strip rolling on a single reversed cold mill are calculated for normal rolling and the rolling considering the effects of different roll speeds (IPV rolling).As regards calculation conditions, the following four items are considered .,.. (1) maximum output torque of the mill motor, (2) maximum torques limited by mechanical strength of the mill drive sys.tem, (3) rolling force to maintain the flatness of the strip and (4) "the neutral points are in the roll gap. Considering rolling conditions, the effects of the roll diameter (400 mm and 600 mm), the coefficient of rolling friction (μ=0.03, μ=0.06) and the flow stress of the mild steel and high-strength steel (1.5 times as strong as mild steel) are all examined.As result, (1) total number of passesin IPV rolling is about 30% less than that of normal rolling, (2) there is no rolling limit of minimum thickness in IPV rolling, (3) the thin strip can be rolled under the conditions of larger work roll diameter, higher coefficient of rolling friction and higher flow stress of the rolled material than ordinary rolling, are obtained.
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