Lipetsk State Technical University (Lipetsk, Russia):

A. V. Polyakov, Post-graduate Student, e-mail: Pool_Akov@mail.ru
R. Shatshu Netshunzim, Post-graduate Student
I. P. Mazur, Dr. Eng., Prof., Head of Metal Forming Dept., e-mail: mazur@stu.lipetsk.ru

When alternating reduction in vertical and horizontal rolls, occurring in a roughing group of continuous wide-strip hot rolling mills, the metal transitions from the lateral edges and ribs of a slab to horizontal surfaces of the hot-rolled breakdown. In this case, the metal in the edge region is shifted to the longitudinal axis of the hot-rolled breakdown. The magnitude of the metal movement, and with them the edge defects formed on the continuously cast slab, on the horizontal surfaces of the hotrolled breakdown directly affects the value of the side trim in subsequent technological operations. In this paper, the processes of metal flow in the edge area during reduction in the universal roughing stand are considered. The influence of a number of technological parameters and modes of adjustment of the vertical rolls operation, such as the value of side reduction, the friction coefficient and the speed mode of vertical rolls, on the value of metal displacement to the longitudinal axis of the hot-rolled breakdown is investigated. The critical point at which the metal displacement changes its direction is described. The studies were carried out using a mathematical model of slab reduction based on the finite element method using the SIMULIA ABAQUS software package.

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