Lipetsk State Technical University (Lipetsk, Russia):

S. M. Belskiy, Dr. Eng., Prof., E-mail: Belsky-55@yandex.ru
A. N. Shkarin, Post-graduate Student

Novolipetsk Steel – NLMK (Lipetsk, Russia):
V. A. Pimenov, Cand. Eng., Senior Researcher, Chief Specialist

The geometric parameters describing the features of the crosssectional profile of a hot-rolled strips do not give a complete picture of the flatness acquired by the cold-rolled strips rolled from these strips. An additional analysis, the results of which are presented in Message 1, showed that there are four characteristic classes of cross-sectional profiles of hot rolled strips that have a significant effect on the shape of the strips during cold rolling, three of which negatively affect the flatness of the cold rolled strips. The cross-sectional profiles of hot-rolled strips with a concave middle part and / or marginal thickenings lead to the appearance of edge waviness, peak-like cross-sectional profiles cause central warping. Therefore, the actual task is to determine the factual shape of cross-sectional profile. 6th order polynomials were used to digitalize and parameterize hot-rolled profile. As a result, we developed analytic function of the transverse profile, which keeps important information about its near-edge areas and features in the middle part. To assign a specific crosssectional profile of a hot-rolled strip to one of four characteristic classes of cross-sections, mathematical software was developed, called a classifier, and implemented with the programming environment R. To classify the profiles of the hot-rolled cross-section according to characteristic classes, a linear discriminant method was used as a machine learning method analysis. The result is an adequate mathematical model for recognizing the shape of the cross-sectional profile.
The study was carried out with the financial support of the Russian Foundation for Basic Research within the framework of scientific project No. 19-38-90257.

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