Abstract. A method has been proposed and calculations have been made for the diameters of roll barrels of TPU 8-16" rolls with pilgrim mills of ChelPipe JSC for rolling pipes with a diameter of 273 to 630 mm, based on the rollback path of feeders 1450±25 mm. For translation of the existing park of rolls in the amount of 120 pairs, a method is proposed for increasing the diameters of roll barrels for rolling pipes with a diameter of 273, 299, 325, 351, 377, 402, 426, 450, 465, 530, 550, 610 and 630 mm, including the existing park of rolls made of carbon steel type 45L with a diameter of 980, 1025 and 1045 mm, machining of barrels and roll necks, multiple rough machining of the profile of the roll groove for surfacing on roll lathes according to a copier or program, multiple surfacing of the working profile of the rolls with wear-resistant heat-resistant wire on a surfacing installation according to a copier with an allowance for machining, multiple machining on roll lathes with subsequent grinding of roll gauges to specified dimensions, it is proposed to determine the diameters of the roll barrels according to the specified polishing coefficients and the rollback path of the feeder. The analysis of the current state of the method for the production of seamless pipes at pipe-rolling plants with pilgrim mills and the existing methods for calculating roll sizing showed that in order to expand the size range towards increasing diameters, it is necessary to further improve the sizing of rolls and the technological process of pipe production. For the first time in the world practice, in rolls with a barrel diameter of 1150 mm in a caliber of 560 mm, pig pipes 550x40x5800-6000 mm in size made of steel grade 08X18H10T-Sh were rolled for subsequent machining-boring and turning them into commercial pipes 530x16-25 mm in size according to TU 14- 3R-197-2001 for nuclear facilities.
Keywords: pilger mill, pilger mill rolls, seamless hot-rolled pipes, feeding value, polishing ratio, calibration pilger rolls, longitudinal and transverse different-thickness of pipes, the way the rollback feeding device, fusing.