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

Edge defects, formed on the continuously cast slab before entering the hot rolling mill, in the wide-strip mill roughing group move from the lateral faces and ribs of the slab to the upper and lower surfaces of the strip plate. This process is facilitated by alternating reduction in vertical and horizontal rolls. The process and reasons for the transition of metal from the ribs and lateral faces of the slab, as well as the defects located on them, to the upper and lower surfaces of the rolled stock during rolling in universal stands of the roughing group of the continuous wide-strip hot rolling mill have been considered. The amount of movement of defects on the horizontal surfaces of the rolled stock directly affects the amount of side trim, which is necessary to ensure the removal of edge defects in subsequent production areas. A mathematical model of slab reduction based on the finite element method using the SIMULIA ABAQUS software package is presented. The mathematical model includes the reduction of the continuously cast slab in three freestanding stands, consisting of vertical and horizontal rolls. The influence of a number of technological parameters and modes of adjustment of the vertical rolls operation, such as the magnitude and distribution of lateral reduction, speed mode, on the amount of metal displacement to the longitudinal axis of the roll has been investigated.

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