National University of Science and Technology MISIS, Moscow, Russia

D. A. Chislov, Postgraduate Student, Dept. of Metal Forming, e-mail: dan.chislov@yandex.ru
A. S. Aleshchenko, Cand. Eng., Associate Prof., Head of the Dept. of Metal Forming, e-mail: aleschenko.as@misis.ru
V. V. Frolov, Postgraduate Student, Dept. of Metal Forming, e-mail: vyachfrol0ff@yandex.ru

This paper examines the development of an unfavorable stress-strain state during hot screw two-high rolling of small-diameter bars, which is the main stage in the production of long products. An innovative solution is proposed, employing non-driven disks similar in shape to Discher`s disks but used for a fundamentally different purpose: to create favorable deformation conditions and reduce tensile stresses in the central zone of the bar deformation zone, which arise due to the specific nature of metal flow. The results of numerical modeling of the rolling process using the QForm software package are presented, demonstrating the effectiveness of the proposed approach. The feasibility of using a spring-loaded disk design to improve process accuracy and minimize the risk of surface defects is substantiated. This is a relevant task in the context of complex forming during helical rolling of bars.

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