Numerical simulation of bending deformation induced by multi-seam welding of a steel-pipe structure

Abstract

Longitudinal bending deformation, often induced during gas metal arc welding of long pipe structures, plays a negative role in the accuracy of assembly, external appearance, and various strengths of welded pipe components. In this paper, an experimental and numerical study of pipe welding distortion is presented. A 3D thermo-elastic-plastic finite element model for multi-seam welds (composed of longitudinal (L-seam) and circumferential (C-seam) welds) of pipe components was developed to predict longitudinal bending deformation. The finite element method and experimental results demonstrate good agreement. Therefore, the proposed model can accurately predict welding distortions in multiseam welded pipe structures. Moreover, the results reveal clear distinctions between the longitudinal bending deformations induced by L-seam and C-seam welds due to different selfrestraint strengths. Finally, another characteristic, the bending angle, is analyzed. Linear and nonlinear relationships are observed between the sine of the bending angle and weld length for L-seam and C-seam welds, respectively.