Finite Element Simulation of the Influence of the Bending Roll Profile on the Stress-Strain State of Billets for Longitudinal-Welded Rolled Pipes

Abstract

AbstractIn this paper, we describe 3D finite-element models for the study of billets used in pipe rolling and made of steel sheets thicker than 25 mm. Relying on 3D modeling with the MSC Marc software package, we study how several alternatives of lowering the upper roller of a traditional profile affect the geometry of the resulting pipe billet and, also, the distribution of deformations and stress during the bending process. We manage to reduce the computation time for a 3D model with a finite element mesh containing more than one million nodes, which is possible through multi-threaded computation distributed over the nodes of a computing cluster. The main load during the first pass of a bending tool with a traditional profile is exerted on local areas of the outer surface of the pipe billet. Those areas are located on the border of the edges and the chamfers of the weld groove. Plastic deformation occurs on them and leads to local thinning of the pipe billet. We suggest alternatives for changing the profile of the bending tool to create additional contact pads during the bending process.KeywordsLongitudinal welded pipesFinish bendingFinite element methodBending roll shapeParallel computationsClusterStress-strain state