Fundamental studies on in-process controlling angular distortion in asymmetrical double-sided double arc welding

It is extremely important to reduce and control residual angular deformation from the welding processes which has negative effects on fabrication accuracy in the manufacturing industry. A new method, asymmetrical double-sided double arc welding (ADSAW), is studied due to control residual angular distortion. Because arc distance between fore and rear torches and welding parameters are the key effective factors of angular distortions in ADSAW, but it is not clear about the effects of them on the angular distortions. In this study, experiments are carried out to investigate the thermal character and the effects of arc distance and welding parameters on the angular distortion in ADSAW. Meanwhile, a 3-D thermal elastic plastic finite element model is developed to simulate transient temperature and welding deformation with different arc distance and heat input. The simulated results are in a good agreement with the experimental measurements. The influence on welding deformation of the arc distance and heat input is investigated. In addition, the distortion mechanism and control strategy of angular distortion are clarified through numerical simulation.