Study of the Process of Continuous Forming of Welded Pipes in the TESA Line Using Coiling Schemes with Alternating Bending of the Pipe Billet

A comparative analysis of the deformation schemes of the pipe billet (PB) in traditional and alternating curvature configurations of forming mills is presented. Schemes utilizing alternating bending of the pipe billet with two and three cycles of alternating bending are examined. For the pipe electric welding mill (TESA) 10–60 and the pipe size of 50 × 1.5 mm, a calculation of the stress-strain state based on fixed fibers of the PB at the deformation focal point is provided, along with an analysis of the profile quality during the deformation process. The analysis showed that the longitudinal strain values do not exceed the permissible limits for this type of pipe size.