Lipetsk State Technical University (Lipetsk, Russia):

V. N. Soloviev, Cand. Eng., Associate Prof.
E. B. Bobkov, Cand. Eng., Associate Prof., e-mail: bobkov0011@yandex.ru

The possibilities of increasing the productivity of a continuous wide hot strip rolling mill in the production of semifinished rolled stock from low-carbon steels with the provision of the required mechanical properties along the length of cold-rolled steel have been investigated. The work presents the results of industrial research on the production of semifinished rolled stock with the use of increased acceleration, which provides a “reverse temperature wedge” and cold-rolled sheet for subsequent cold stamping. The increase in productivity is achieved by reducing the machine time of rolling strips in the finishing group of stands of a continuous wide hot strip rolling mill. In this case, the temperaturedeformation conditions for the formation of the structure of the rolled stock are not constant along the length of the strip, which can lead to the difference in the mechanical properties along the rolled stock length. In the cold rolling shop, it is difficult to assess this due to the influence of many factors during the processing of rolled stock in the IV production area, therefore, changes in mechanical properties were assessed at the last stage - cutting the coils into sheets. It was found that the use of rolling modes with a “reverse temperature wedge” makes it possible to reduce the machine time of strip rolling in the finishing group of stands of the continuous wide hot strip rolling mill by 8–10%. “Reverse temperature wedge” for the semifi nished rolled stock up to 50 °C provides the mechanical properties required by GOST along the length of cold-rolled strips.

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