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Development of rolling stock, increase in the speed of transportation, load-bearing capacity of highways and their length requires constant improvement of the production technology for railway rails. Modern rail-beam mills have in their composition a continuously reversible group of stands, which includes universal stands. Rolling of rail profiles in universal calibers is radically different from rolling in two-roll calibers, and at the moment is not well studied, both theoretically and practically. The article defines the conditions for feasibility of the rolling process in universal calibers with a pair of non-drive rolls, taking into account the values of active (reserve friction forces) acting from the drive rolls and reactive forces from the non-drive rolls and roller fittings. The energy balance method solves the problem of determining the back-up force required for deformation in non-drive rolls. When solving the equation of equilibrium of forces in the deformation center formed by the drive rolls, the reserve of friction forces is defined, the magnitude of which largely determines the possibility of the rolling process. Theoretical dependences are obtained for estimating the power balance during rolling in universal calibers of modern rail-beam mills, taking into account the reserve of friction forces provided by the drive rolls and the support required for deformation in non-drive rolls. Information about the force conditions in a universal caliber is necessary to analyze the feasibility of the rolling process in it under various deformation modes and to clarify the drawing coefficients for elements of the resulting profile. Dependencies are proposed that allow estimating the consumption of the reserve of friction forces for the operation of roller fittings serviced by universal caliber. The well-known formula of A.I. Tselikov and A. I. Grishkov on the definition of broadening was clarified in relation to rolling in universal calibers with two non-drive rolls. The support from the non-drive rolls side effects the change in size of sole and head of the rail profiles.

Аt present, there is a steady tendency to increase volume of i dustrial and civil construction in Russia and abroad. This in turn makes it necessary to enhance production of structural sections and in particular – reinforcing bar. One of the promising ways to increase production of reinforcing bar at existing rolling mills is development of rollingseparation technology. This technology provides growth in productivity of existing small-grade mills and reduces energy costs without large capital expenditures. However, despite its apparent simplicity, introduction of rolling-separation technology at existing enterprises causes difficulties associated with insufficient coverage of this experience in literature. The article presents experience of introduction of the rolling-separation technology on operating continuous small-grade mill. The research was carried out on equipment available in the workshop and used to monitor load of the main engines. Features of energy costs distribution on stands were studied at classical rolling and with the use of technology of rolling-separation of reinforcing bar No. 10, No. 14 made of 35GS and 3PS steel. Experimental graphs of the main engines of the rolling mill load show redistribution of energy consumption in stands for roughing, intermediate and finishing groups when using rolling-separation technology. Data on application of the main engine power and distribution of the specific load on the stands in classical rolling method and using rolling-separation technology are presented in graphic form. Analysis of the received data allowed us to reveal features of energy consumption at development of rolling-separation technology during operation. It is shown that use of this technology leads to additional load on stands of finishing groups. Energy savings during introduction of rolling-separation technology were quantified, and it was found that with a decrease of the rebar number, efficiency increases. Reduction of energy consumption during development of this technology in current production is associated with a decrease in machine time.