Novolipetsk Metallurgical Plant (Lipetsk, Russia):

V. A. Pimenov, Cand. Eng., Senior Researcher, Chief Specialist, e-mail: pimenov_va@nlmk.com
D. A. Kovalev, Cand. Eng., Acting Director of Directorate for Development of NewTechnologies, e-mail: kovalev_da@nlmk.com
M. A. Dagman, Specialist, Rolling Production Directorate

Lipetsk State Technical University (Lipetsk, Russia)
I. P. Mazur, Dr. Eng., Prof., Head of Metal Forming Dept., e-mail: mazur@stu.lipetsk.ru

On the basis of the physical laws of the rolling process, an integrated mathematical model of the formation of the cross profile of a hot-rolled strip on a broad-strip mill was built, including models of the grinding profile of rolls with axial shift, bending of rolls, elastic flattening in contact with the strip, thermal expansion of the barrel, and wear of the work rolls surface during rolling. When predicting the wear of rolls, the uneven pressures in contact with the strip were taken into account using a generalized model and the displacement of the strip along the length relative to the mill axis using a stochastic model. The adaptation of the wear model according to the experimental data based on the comparison of the predicted and measured wear of rolls after rolling is carried out and the adequacy of the developed integrated model of profile formation is shown. This model was used on the 2000 broadband mill to improve the hot rolling technology and optimize the planning of assembly batches, primarily in the production of large volumes of rolled electrical steels with high requirements for the accuracy of the cross section. Proposals are formulated for the development of criteria for optimizing hot rolling technology according to the characteristics of the cross section, which ensure metal savings, increase the broadband mill productivity, and maximize consumer properties.

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