Cherepovets State University, Cherepovets, Russia
N. L. Bolobanova, Dr. Eng., Associate Prof., Head of the Dept. of Metallurgy, Mechanical Engineering and Technological Equipment, e-mail: nlbolobanova@chsu.ru

Moscow Polytechnic University, Moscow, Russia
R. L. Shatalov, Dr. Eng., Prof., Dept. of Materials Forming and Additive Technologies, e-mail: mmomd@mail.ru

Moscow Polytechnic University, Moscow, Russia¹ ; Severstal-Project Ltd., Cherepovets, Russia²
M. A. Bolobanov, Postgraduate Student, Dept. of Materials Forming and Additive Technologies¹, First Category Specialist², e-mail: ma.bolobanov@severstal.com

The paper presents the results of numerical simulation of the variable lateral reduction process of strips in a vertical stand of the roughing group of a wide-strip hot rolling mill. The simulation was performed with the aim of developing an engineering methodology for calculating reduction schedules to reduce the crop loss at the strip ends and increase the yield of sound metal. The simulation was carried out in the DEFORM-3D software package based on the finite element method for a slab with a cross-section of 1290×250 mm. The adequacy of the model was confirmed by comparing the width profile of the virtual transfer bar after stand No. 5 with industrial measurement data. Numerical simulation confirmed the effectiveness of the variable lateral reduction technology for minimizing geometric deviations on the end sections of the transfer bar in the roughing group of a wide-strip hot rolling mill. The best results were shown by the schedule with increased length and magnitude of the compensating vertical roll gap opening. During the rolling of strips from a slab with a cross-section of 1290×250 mm in stand No. 5 of a continuous wide-strip mill, rational parameters for variable lateral reduction were determined: an increase in the vertical roll gap by 15–20 % relative to the nominal value over extended sections at the beginning and end of the strip. The developed deformation schedule allows reducing the front-end narrowing to 7 mm and minimizing the formation of longitudinal protrusions (“ears”) on the rear end of the rolled product to 114.6 mm. Based on the identified patterns, practical recommendations are proposed for setting up variable reduction schedules to reduce the crop loss at the head and tail ends of the strip and increase the yield of sound metal. The obtained results provide a practical basis for the implementation of variable lateral reduction technology to improve production efficiency.

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