Preemptive weld overlay (PWOL) for dissimilar metal weld of the Pressurized Water Reactor using a temper bead welding procedure. Overlay repairs were completed on dissimilar metals within the pressurizer, and on surge nozzles, safety/relief nozzles and spray nozzles.
Liburdi’s engineering staff designed and manufactured the custom equipment for the overlay welding in tandem with their weld development team, who were responsible for the development of the weld procedure and WPS/PQR according to ASME section IX. The weld development included all aspects from mechanical and metallurgical testing of the samples, to the detailed setup of the torch, bead sequence and overlapping for the various welding positions to maintain the proper quality and results. Once developed, Liburdi was tasked with the training and supervision of the welders and technicians in both Canada and Taiwan, using an inhouse mockup. Once trained, the welders were certified and deployed to site. While on site Liburdi offered continued support through welding supervision and E-Tech support throughout the successful completion of the project.
Liburdi added continuity and expertise to the project by providing all of the equipment, procedures, training and support for the multiple outages during the multi-year time frame. Using Liburdi’s remote welding equipment, multiple cameras and vision systems allowed the project to reduce welder’s dose rates.