Ural Federal University (Ekaterinburg, Russia):

D. A. Pavlov, Cand. Eng, E-mail: d.a.pavlov@urfu.ru
M. V. Erpalov, Cand. Eng, E-mail: m.v.erpalov@urfu.ru
G. V. Shimov, Cand. Eng, E-mail: g.v.shimov@urfu.ru
E. A. Pavlova, Post-graduate student, E-mail: pavlovda1989@mail.ru

In the course of computer modeling, the eff ect of the material properties on the inhomogeneity of the distribution of the strain along the pipe cross section in the deformation region was investigated. The study was carried out for a hardened, non-hardened and softened material during deformation. As a criterion for the inhomogeneity of the distribution of the strain, the standard deviation of the strain in the deformation region was used. It is established that the maximum standard deviation of the strain, and, consequently, the deformation inhomogeneity in the deformation region is observed during the rolling of pipes from the softened material, and the smallest for pipes made of hardened material. The lowest value of the wall thickness variation in the pipes, and the largest standard deviation of the strain, are obtained for tubes of softened material. It is established that when lengthwise rolling on a stub mandrel it is possible to reduce the transverse difference in the pipe by selecting rational temperature-velocity regimes of deformation, which ensure a reduction or absence of the hardening effect.
The study was made within the base part of State assignment in the field of scientific activity № 11.9538.2017/8.9, supported by the Program 211 of the RF Government (agreement № 02.A03.21.0006).

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