Investigation of angular deformation control for T-joint rib using multi-point constraint method

Abstract

The circular rib is a crucial component of large pressure vessels, and its cross-section is primarily a T-joint structure. The double-sided arc welding (DSAW) process is an advanced technology for T-joint connection. However, during the T-joint welding process, harmful deformation still occurs in the form of angular deformation, including web and flange angular deformation. This paper proposes an innovative multi-point array constraint method to control the angular deformation of the rib based on the DSAW process for circular ribs. The welding deformation of the T-joint rib under multi-point constraints is studied using both numerical and experimental methods. The results of the numerical and experimental are consistent, with a relative error of no more than 12%. The multi-point constraint method is found to control angular deformation effectively, with the maximum angular deformation of the web not exceeding 1.77 mm and that of the flange not exceeding 0.45 mm after welding and releasing the constraint. The deformation control is significantly better than that of the rigid jig. Moreover, the coupling deformation of the web and flange caused by double-sided heat source and multi-point constraint forms an overall bending deformation. The deformation trend of each welding process is the same, with the main deformation occurring in the stage of releasing the constraint.