Page 26 - ITATUBE Journal 1 2020

Technical Papers
with a serial number 16, in contrast to the one-radius ( 1.032) and the known three-radius ( 27.659 mm,
3.300 mm, 1.030) calibers:
• radius of the proposed caliber ( 17.540 mm,
2
29.347 mm, 1.851 mm, 0.010 mm, 30.262 mm,
–10.709 mm, 33.591 mm, 7.990 mm, 1.022), in the top area is smaller than the average radius of the caliber
(Fig. 4);
• radial compression gains maximum values in the middle of the caliber (when
), rather than monotonically decrease from top to release (Fig.5);
• the initial contact of the workpiece with the roll happens not at the top of the caliber, but in
its middle zone (Fig. 6).
The fact that the radius of the proposed caliber is smaller than the radius of the known
caliber at (Fig. 7) and radial compression gains its maximum values not at
the top of the caliber but at (Fig. 5), causes "bilateral" flow of the forming metal from the middle of the caliber in the direction of its top and release. In terms of the formation of the transverse wall thickness variation, such deformation conditions are more optimal than the conditions under which there is a one-way flow of metal in the direction from the top to the release of the caliber. This was confirmed by industrial tests under conditions of Pipe Rolling Machine 30-102.
Literature
1. Patent 132091 Ukraine MPK (2006.01) B21H 8/02, В21В 27/02 Caliber of a roll for lon- gitudinal rolling of pipes. Y.G. Gulyaev, I.P. Khatskelian, O.V. Lutsenko et al. Applied 07.09.2018; Published 11.02.2019, Bul. No3. – 5 p.
2. Gulyaev Yu., Shifrin Ye., Koriaka N. Optimization of the roll pass design for continuous longitudinal tube rolling // “ITA Tube Journal“. – 2017, No4 (November). – S. 16-20.
3. The Mathematical Model of Formation of the cross–sectional Wall Thickness Nonun- formity during Longitudinal Plugless Tube Rolling / G.I. Gulyayev, Yu.G. Gulyayev, Ye.I. Shyfrin, N.Yu. Kvitka, K. Sawamiphakdi. – Material Science & Technology Con- ference Proceedings. AIST/TMS. – Pittsburgh (Pa., USA), 2005. – P. 15–25.
4. Optimization of the Roll Design Parameters and Deformation Schedules in the Continu- ous Plugless Tube Rolling Process / G.I. Gulyayev, Yu.G. Gulyayev, Ye.I. Shyfrin, N.Yu. Kvitka, C.V. Darragh. – Iron & Steel Technology Conference Proceedings (AIS- Tech’06). – Cleveland (Ohio, USA), 2006. – P. 112–121.
Nataliia Kvitka, M.Sc. (eGestures LLC, Toronto, ON, Canada) e-mail:
nataliya.kvitka@gmail.com
Nataliia Koriaka (ITA Representative in CIS countries, Dnepr,Ukraine) e-mail: koryakan@gmail.com
ITAtube Journal No1/July 2020
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