23th issue of the journal "KB"

Abstract. The article presents an example of simulation rolling rails in the roughing stand 5th pass in two versions: with and without guide system use, as initial conditions of simulation problem. The simulation results showed that in order to obtain the most reliable data, both on the geometry of the shaping process and on the analysis of emerging loads, it is necessary to use a model not only of the roll grooves, but also of the guide system. An important factor is the choice of the material of rolled billet and coefficient, including with the guide elements. The coefficient of metal friction on the guide elements, for 76XF rail steel, was according to Siebel 0.176. The application of this method will make it possible to predict the permissible pressure, the behavior of the strip and the design of the applied guide elements at the design stage.
Keywords: guide system, rail rolling simulation, Deform 3D, 76XF rail steel, friction force, Siebel friction coefficient.

Abstract. The paper presents a study of the influence of temperature-strain conditions of the rough rolling stage on the size of recrystallized austenite grains in the production of low-alloy structural steel.
Keywords: heavy plate mill, rough rolling, microstructure, temperature-strain conditions, austenite grain size.

Abstract. A technological process for the production of bimetallic mandrels from bimetallic centrifugally cast billets, with increased resistance of the interlocks from crushing and breakage from dynamic shocks during priming and removal of stuck mandrel from pipe sleeves, for rolling hot-rolled pipes with a diameter of 219 to 610 mm on TPU with pilger mills. Theoretical data on the comparative results of the production of hollow mandrel blanks from ingots-blanks of ESR steel 25Х2М1Ф and from centrifugally cast bimetallic blanks are presented.
Keywords: solid, hollow and bimetallic mandrels for pilger rolling of pipes, fire cracks, heat treatment.

Abstract. To increase the accuracy of pipes in terms of wall thickness, the optimal barrel diameters of TPU rolls 8-16" with pilger mills for rolling pipes with a diameter of 273 to 630 mm were deter-mined, the optimal angle of transverse release of the polishing section and longitudinal release of rolls for rolling pipes with a diameter of 508, 530, 550, 610 and 630 mm, its influence on the transverse wall difference of pipes and the dependence of the wall difference of pipes with diameters of 508, 530, 550,610 and 630 mm on the polishing coefficient is theoretically substantiated.
Keywords: pilger mill, pilger mill roll, mandrel, striker, polishing section, longitudinal tapping angle, transverse tapping angle, cross-helical rolling mill, process furnace, sleeve, pipe, feeding apparatus, feed amount, calibrating mill, straightening mill.