Welding Distortion of a Thin-Plate Panel Structure

Welding thin-plate panel structures often results in warping of the panels. Several mitigation methods, including preheating and prestressing the plates during assembly, have been investigated and used by some fabricators. This paper studies the distortion mechanisms and the effect of welding sequence on panel distortion. In this study, distortion behaviors, including local plate bending and buckling as well as global girder bending, were investigated using the finite element method. It was found that buckling doesn’t occur in structures with a skin-plate thickness of more than 1.6 mm unless the stiffening girder bends excessively. Warping is primarily caused by angular bending of the plate itself. The joint rigidity method (JRM) was found to be effective in determining the optimum welding sequence for minimum panel warping.