9.3 – Design of Welded Joints – Determining Stress State

The VDI Richtlinien titled ”Rechnerischer Festigkeitsnachweis fur Maschinenbauteile” was published by Forschungskuratorium Maschinenbau (FKM) in 1998; it provides designers with a design method of a standardized approach on a new basis, even for the stress analysis of welded structures. One of the essential criteria for designing welded seams for static stress and fatigue is knowledge of the stress state in the seam and its surroundings. Erwin Haibach proposes to determine the so-called structural stress characterizing stress state of welded seams along the Haibach line. In our presentation, a brief introduction to the designing of welded structures according to FKM will be followed by a presentation of results of FE analyses to demonstrate the use of stresses interpreted along the Haibach line as structural stresses. Our research and development activities were performed on assignment by and in cooperation with Knorr Bremse Hungaria Kft.