INFLUENCE OF WELD GEOMETRY ON CYLINDRICAL WELDED JOINT LIFE
Jelena M. Djoković1, Ružica R. Nikolić2, Jan Bujnak3, Aleksandar S. Sedmak4
1)University of Belgrade, Technical Faculty in Bor, Serbia,
2)University of Kragujevac, Faculty of Engineering & Univ. of Žilina, Slovakia, Research Centre
3)Univ. of Žilina, Faculty of Civil Engng., Slovakia
4)University of Belgrade, Faculty of Mech. Engng., Serbia
Weld geometry influence on the fracture mechanics parameters of a cylindrical welded joint subjected to combined load is considered in this paper. Three shapes of fillet welds are analysed: triangular, rounded convex, and concave. Stress intensity factors (SIF) are calculated analytically, based on the Linear Elastic Fracture Mechanics (LEFM) concept. Existence of the weld and load are taken into account through corresponding correction factors. In the case of the triangular fillet weld, the normalized Mode I stress intensity factor decreases with crack length, while the normalized Mode III stress intensity factor increases. The same is valid in the case of a convex fillet weld. In the case of the concave fillet weld, both stress intensity factors increase with crack length. Based on the obtained results, it is concluded that with respect to the fracture resistance, the convex fillet weld exhibits the best properties.
Keywords: cylindrical welded joint, corner joint, stress intensity factor, working life, fracture resistance