Novolipetsk Steel Works (Lipetsk, Russia):

V. A. Pimenov, Head Specialist of Technology Development Administration
A. V. Shamrin, Leading Engineer of Group of Lubricating and Cooling Materials and Rolling Rolls

Lipetsk State Technical University (Lipetsk, Russia):
A. V. Polyakov, Post-Graduate Student of the Chair of Metal Forming
I. P. Mazur, Dr. Eng., Prof., Head of the Chair of Metal Forming, e-mail: mazup_ip@mail.ru

Edged defects, formed during the process of metal casting at curved continuous casting machine and during hot rolling are removed in the subsequent trimming of the strip edges. The width of the cut edges depends, among other things, on the location of the edge defects. To reduce the width of the side trim, it is proposed to reduce the transition of metal from the side faces of slabs to the upper and lower surfaces of the strip by slab reduction in a special way calibrated vertical rolls of the first stand of the continuous wide hot strip rolling mill. In this paper, a comparison of the passes used on the vertical rolls of the first universal mill stand 2000 at Novolipetsk Steel (NLMK) is presented. To study the displacement of the metal during deformation of the slab in calibrated vertical rolls, finite element modeling was performed using the SIMULIA ABAQUS software package. Formation of a concave side face of the slab during reduction in the vertical rolls with the new grooves is confi rmed. The movement of points along the edge to the longitudinal axis of the slab has decreased compared to reduction in the passes currently used in NLMK mill 2000. The evolution of the proposed grooves between the stages of industrial testing is described. It is confi rmed that there is no infl uence of displacement of edged defects on the probability of breakage at the following alterations on the example of electrotechnical steels of the fourth alloying group.

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