Rolling and Other Metal Forming Processes | |
Название | Improvement of the method for calculating metal shape change in a finishing universal three-roll rail pass |
DOI | 10.17580/chm.2023.03.05 |
Автор | V. V. Dorofeev, A. V. Dobryansky, A. V. Golovatenko, D. E. Pervushin |
Информация об авторе | EVRAZ United West Siberian Iron and Steel Works JSC, Novokuznetsk, Russia: |
Реферат | An improved method for calculating the metal deformation in a finishing universal threeroll pass during rolling of railway rails is presented. The calculation of metal deformation in a finishing universal three-roll pass according to the generally accepted method, including a uniform distribution of deformation over all profile elements, to exclude the possibility of metal flowing from one part of the profile to another, does not provide the same forward speed of the profile elements when exiting the pass. The discrepancy between the forward speeds according to the profile elements leads to the bending of the front end of the breakdown bar towards the element having a lower forward speed, and the impossibility of the task of breakdown bar into a specialized hardening device when hardening the rails from rolling heating by air. In order to obtain a straight–line exit of the rail breakdown bar from a finishing universal three-roll pass, in which the rail foot is formed in a three-roll area, and the rail web and rail head are formed in a two-roll area, with the roll unjamming in the middle part of the rolling surface, it is proposed to calculate the metal deformation when exit from a finishing universal three-roll pass at fulfillment of the condition of equality of the forward movement of the rail foot and the rail head breakdown bar at the exit from the deformation zone, the total components of which are the movement of the metal from the speed of the longitudinal plastic displacement during reduction and from the horizontal component of the circumferential speed of the rolls: Vв.г(1 + Sг) = Vв.п(1 + Sп), where Vв.г and Vв.п are the horizontal components of the circumferential speed of the rolls along the head and bottom of the profile, respectively, m/s; Sг and Sп – forward flow of metal during rolling from the reduction of the rail head and rail foot, respectively. To fulfill this condition, when the inequality of horizontal components of the circumferential speeds of the rolls that form the rail head and the rail foot in a finishing universal three-roll pass such deformation values of these elements are determined so that the values of the speeds of plastic displacement of the metal from the reduction of these elements make it possible to equalize the forward speeds of the exit of the rail head and the rail foot from the pass. |
Ключевые слова | Railway rail, calculation method of metal deformation in gauges, universal three-roll rail pass, forward speed of profile elements during metal deformation in gauges, relative compression of profile elements, forward flow of metal during rolling |
Библиографический список | 1. Bakhtinov Yu. P., Shternov M. M. Grooving of rolls. Moscow : Metallurgizdat, 1953. 783 p. |
Language of full-text | русский |
Полный текст статьи | Получить |