Study on influence of gas cutting on welding deformation after submerged arc welding at removing constraint jig plates

In order to investigate the effect of gas cutting during removal of constraint jig plates on deformation after submerged arc welding, the authors have conducted the experiments on a series of processes using a constraint jig plates in a test specimen modeling the deck of a steel bridge. In this paper, an Idealized explicit FEM developed by the authors is applied to investigate in detail the factors that cause springback deformation during the gas cutting of the constraint jig plates.A series of welding and cutting processes using a constraint jig plates were modeled, and then a three-dimensional thermo-elastic-plastic analysis was performed using the Idealized explicit FEM. As a result, it is confirmed that the experimental and analytical results were in good agreement, and the validity of the analysis method was demonstrated. In addition, it is found that the inherent deformation during gas cutting had a significant influence on the springback deformation by the numerical analysis. Then, we proposed a simplified mechanical model to estimate the deformation during gas cutting. As a result, it was found that the proposed mechanical model showed quantitatively good agreement with the springback deformation.