A weld overlay (WOL) following the general guidelines of ASME Code Case N-740-2 was successfully installed in March of 2018 on a dissimilar metal weld joining the super emergency feedwater1 piping to steam generator (SG) at the Dukovany nuclear power plant (NPP) in the Czech Republic. The repair was necessary due to stress corrosion cracking detected in the super emergency feedwater nozzle to safe-end dissimilar metal weld. This was the first WOL installed in the Czech Republic and represents a significant step towards further acceptance of this proven repair technology in Europe. The WOL repair approach was accepted by the Czech regulator, and two different inspection agencies, following successful mockup demonstrations, welding procedure qualification, nondestructive examination demonstrations and weld residual stress analyses. This paper describes the preparatory work as well as field deployment of WOLs in the Czech Republic.

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