Lipetsk State Technical University, Lipetsk, Russia

S. M. Belsky, Dr. Eng., Prof., Dept. of Metal Forming, e-mail: belsky-55@yandex.ru

When rolling strips in a continuous wide-strip hot rolling mill (WHR), the most common violations of the geometric parameters of the strips in the roughing group of stands are the wedge-shaped cross-section profile and the associated camber form of the strips, and in the finishing group of stands, the unsatisfactory convexity of the cross-section profile and the associated non-flatness of the strips. "Camber" is a smooth curvature of the strip in the form of an arc in the horizontal plane. The camber defect is closely related to the cross-sectional profile defect, which is called the wedge. The main causes of wedge-shaped cross-section profiles of hot-rolled strips are vertical and horizontal skew of the working rolls, which occurs due to errors in the installation of the roll fittings, wear on the working surfaces of the roughing stand, and uneven heating of the strips along their width on the drive side and on the transfer side. The wedge-shaped cross-section profile of hot-rolled strips begins to form in the first stands of the roughing group, and the camber-shaped profile caused by the wedge-shaped profile does not appear immediately at the exit of the first stands of the roughing group; it usually appears at the exit of the last roughing stand, when the strip is placed on an intermediate roller table. Non-flatness of hot-rolled strips is most often manifested in the form of two varieties: "edge waviness" and "central buckling". The purpose of this work is to evaluate the reducing of the unevenness in the distribution of elongations across the width of the strip during hot rolling due to the lateral displacement of the metal in the deformation hearth using the variational method.

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