Siberian State Industrial University (Novokuznetsk, Russia):

Peretyatko V. N., Dr. Eng. Prof., Chair of Metal Forming and Metal Science

EVRAZ Consolidated West-Siberian Metallurgical Plant (Novokuznetsk, Russia):
Smetanin S. V., Cand. Eng., Head of the Central Laboratory of automation and mechanization of rail production, e-mail: Sergey.Smetanin@evraz.com

The article presents the results of scientific-practical work on research and optimization of the process of hot rolling of a rail profile in the finishing and pre-finishing 4-roll slitting passes. As it is known, rolling in 4-roll rail passes is accompanied by various rolling efforts from the side of vertical rollers forming a sole and a head of a profile. It leads to axial displacement of rolls and has adverse affect on stability of rolled profile, from the point of view of positioning of horizontal rollers. This situation requires additional pass setting and can be characterized by ineffi cient use of drive capacity of a rolling stand; this capacity is used for deformation of basic components of horizontal rolls in the direction corresponding the larger deformation force. Investigated 4-roll passes have horizontal driving rolls, while vertical rolls are not driving. One of the most complicated rail profiles that is asymmetric not only in vertical, but also in horizontal direction has been chosen as the research object; it is tram grooved rail. At the phase of investigation of various rolling schedules in 4-roll passes, the factors and levels of their variation have been defined for the purpose of definition of their influence on manufacture of the required profi le using the method of planning of multifactorial experiment. Research performance at the stage of experiment planning has been conducted by means of computer-aided mathematical simulation according to the grounds of continuum mechanics. Mathematical relationships between movable metal volumes and rolling forces applying in horizontal direction, as well as reduction by vertical rollers have been obtained under the developed deformation schedule. Based on computer simulation of rolling schedules, characterized by optimal results, the pilot-industrial rolling processes have been conducted for obtaining the real rolling forces. Good convergence of the results of computer simulation and industrial experiments has been established, and mathematical model for realizing the power effective technology of rolling of asymmetric rail profiles has been developed.

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