Numerical analyses of the influence of tack welding on angular deformation using the finite element method

Abstract

Welding is a fundamental process in the fabrication of structures across various engineering fields. However, process-induced imperfections can compromise structural integrity and service life of components. During the fabrication of T-joints by welding, tack welds are applied to avoid over-constraint of the components, however, the lack of standard for this process could cause an increase in angular deformation. The Republic of Panama is no exception to the problems observed around the world, according PENCYT. This study investigates the effect of tack welds on T-joints. A Thermal-Elasto-Plastic Analysis (TEPA) using the Finite Element Method (FEM) is employed to simulate the arc welding process applied on S355J2 steel structural stiffeners used in the bow and stern of small steel ships. Different tack welding dimensions and sequences are considered. Additionally, a parametric analysis on the finite element dimension in the heat affected zone is conducted to determine an optimal model for this study. Results show that the angular deformation, considering tack welds, increases by 8% to 13% compared to a model without tack welds. This indicates that parameters such as tack weld length, quantity, and distribution have a significant influence on angular deformation in T-joints.