PSI - Issue 42

Mihai A. Popescu et al. / Procedia Structural Integrity 42 (2022) 1626–1633 M.A. Popescu et al. / Structural Integrity Procedia 00 (2022) 000–000

1632

7

Fig. 7. S2 residual stress measurement values.

Fig. 8. Charpy V-notch values and fracture appearance.

The Charpy impact values, shown in Figure 8, are in accordance with the material properties provided by the manufacturers, and are generally positive, although varying slightly. There is one outlier, namely for Specimens A2, where the values for the impact test at - 20 ° C are lower than those at - 40 ° C. This fact can be explained by the presence of a weld defect in the area or a repair to the weld that was undertaken or other impurities, although no defects were seen while the specimens were machined. Another explanation could be provided by the location of this specimen, in the root of the weld, where tack welds are placed before the SAW process and air-arc gauging is performed.

3.2. Conclusions

Most designers and clients outsource the manufacturing of wind turbine support structures, and while following the design and structural integrity standards, they do not take into account the e ff ects of welding residual stress. This study presents the weld characterisation in two bottom sections of an on-shore (S1) and o ff -shore (S2) wind turbine