Strains and Stresses at Welding with Tubular Wires and Swinging the Electric Arc

Abstract

As it is known, starting with the 19th century, the constructions with metallic strength structure have acquired a wide development. From simple supports for various structures to the most complex constructions, we find metallic elements that must be joined together in various ways. One of the simplest methods, constructive and economic, of joining metallic components of a structure is welding. The study presented in this paper deals with numerical determination of the stress and strain states around welded joints in steel sheets, using the finite element method. The studied sample was manufactured by mechanized welding, in protective gas atmosphere, with tubular wires, and swinging the electric arc. The welding was continuous, made in two layers: root and cover. The finite element method can also be used to study the processes that take place during welding. Important thermal phenomena occur in the weld bead during welding. To obtain reliable results, data describing accurately the behaviour in time of the basic and the addition material are needed. According to well-established parameters of the welding regimes, the welding process was modelled numerically. The results were taken from several areas of the sample, both in the base material (sheet metal) and in the addition material (weld bead). Stresses and strains were analysed at various moments of time during the welding process, both for the first welding layer (root) and the second welding layer (cover).