A “commemorative” weld plate, of which about 20 were made after the NRU vessel repair-work was completed in 2010. The artifact consists of a flat aluminum plate, approximately 26 cm square, that was machined on the back side to replicate the NRU calandria-wall thickness adjacent to position J-Rod -41. This position is the location of the critical through-wall leak that created a major interruption in isotope production schedule. A small hole on the back side, to the right of the larger circular hole, simulates the leak position. A 4 cm diameter, circular hole, was remotely cut from the vessel at this location to obtain a specimen for corrosion and surface science examination, as well as to conduct welding trials. The final repair at this location involved tack-welding a plate inside the vessel to cover both the circular hole and the corrosion hole. The plate was then perimeter welded and finally covered with rows of weld buildup to seal the site.
This particular commemorative plate was awarded to Bill Shorter, who played a key role in the repair project. It reads “NRU Reactor Vessel Repair, J-Rod-41 Position, NRU return to Service, 2010 August.”
