СТАТИСТИЧЕСКИЙ АНАЛИЗ И РАСЧЕТ ФОРМОИЗМЕНЕНИЯ МЕТАЛЛА ПРИ ПРОКАТКЕ ДВУТАВРОВЫХ ПРОФИЛЕЙ НА УНИВЕРСАЛЬНЫХ РЕЛЬСОБАЛОЧНЫХ СТАНАХ

Abstract

The most economical way of producing steel H-beam profiles of wide assortment is the rolling on modern universal rail-beam mills equipped with continuous and reversible groups of stands with four-roll universal beam calibers. They are effectively used in the foreign metallurgy for the production of rails and beams. In Russia, the first two such mills are constructed and are currently being developed at the EVRAZ ZSMK (Novokuznetsk) and in the Chelyabinsk metallurgical plant. The proposed new method of calculating the roll pass design for universal rail-beam mills is based on the results of the statistical generalization of existing technological rolling modes of H-beam profiles on the universal beam, rail-beam and section mills equipped with universal stands, as well as on authors’ mathematical model of metal forming by rolling in universal calibers based on variational principle of minimum total power. At the analysis and generalization of existing technological rolling modes of H-beam profiles a statistical sample was formed that includes the main characteristic parameters of calibration: number (N) and H-beam profile type, the number of passes (n), average reduction ratio in each pass (λi), the total (common) reduction ratio (λΣ) for “n” passes and distribution reductions ratio at the passes. The total volume of the sample amounted to 472 points, received at 55 rolls calibrations. Generated sample was investigated using correlation and regression analysis. As a result, regression dependences were obtained for calculation of basic characteristic parameters of calibration. With the application of the developed method roll pass design have been calculated for the finishing rail tandem of universal rail-beam mill for rolling 35B2H-beam. Characteristic features of the obtained mode are almost the same reduction ratio of the neck λш and flanges λф during rolling in every universal caliber and the difference of values λш and λф in passes are 0.4 – 2.4 %, i.e. uniform deformation of the metal is achieved along the profile elements, which contributes to a high quality H-beam. © 2018, National University of Science and Technology MISIS. All rights reserved.