Novolipetsk Iron and Steel Works, Lipetsk, Russia
S. I. Mazur, Chief Investment Customer of the Office of the Managing Director
V. A. Pimenov, Cand. Eng., Head of Technological Projects, Directorate for Development of New Process Technologies, e-mail: pimenov_va@nlmk.com
D. A. Kovalev, Cand. Eng., Director, Directorate for Development of New Process Technologies
N. N. Zhovnodiy, Head of the Dynamo Steel Shop
M. A. Dagman, Senior Engineer, Directorate for Development of New Process Technologies, e-mail: dagman_ma@nlmk.com

The article presents the results of the work on improving the accuracy of the hot-rolled products cross profile, carried out on the NLMK wide hot strip mill 2000. The methods for calculating profile indicators are considered, including original ones developed and implemented on the mill in online mode. New approaches to assessing local thickenings used on the mill 2000 and based on digital filtering of the results of tomographic profile measurement are described. An integrated approach to the problems of improving the accuracy of rolled products is shown, including research and mathematical modeling, improvement and development of technologies, modernization of equipment and control systems. The mathematical model of profile formation developed at NLMK takes into account the geometry of CVC rolls with axial shift and their wear, bending and flattening of the surface, thermal expansion of the barrel, ensures high accuracy of the forecast and is used to optimize the control of axial shift when rolling isotropic electrical steel-rolled products with the highest requirements for the geometric characteristics of the profile. The results of experimental testing of the edge thinning control technology at the 12^th stand of the 2000 mill are presented.

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