Correction of plate welding-induced distortions by multipass line heating

In the present study, an uncoupled 3D thermo-mechanical finite element model is developed to simulate the process of distortion correction in metallic plates deformed by electric arc welding through single- and multiple-pass line heating. In the thermal analyses, a moving heat source (oxyacetylene flame) with a Gaussian distribution is applied to the steel plate surface. In the mechanical analyses, the thermal transients are sequentially applied as loads on the deformed steel plate model. These thermal transients cause reverse deformations in the plate during each time increment. The accumulated plastic deformations can be used to significantly reduce the steel plate distortions caused by the welding process. Thermal- and temperature-dependent mechanical properties, the von Mises yield criterion and kinematic hardening yield rules for the material are considered in the analyses. The objective of this study is to analyze the deformations that occur in welded panels to determine the most efficient way to reduce distortions by the multipass line heating correction method. © 2016, Sociedade Brasileira de Engenharia Naval.