b'Figure 3. Circumferential welding system, currently undergoing out of cell function, verification, and demonstration testing.boiling (~150 C). Once at tempera- emanating from the heated acid bath, ture, the fuel sample is introducedand the impact of those fumes on the to the system, and the acid etchesfacility and other programs, and if it the fuel out of the cladding. Onceis necessary to capture and neutralize dissolution is completed, the acidthose fumes.bath will be neutralized with MgOOnce fuel has been removed from fuel to eliminate the hazardous nitratesrod segments, final preparations for and then solidified using a WIPP BoKrefabrication may begin. Refabrication approve sorbent. A demonstrationincludes welding on new endcaps to of this procedure was performed atthe fuel segment, which requires that the Analytical Laboratory using a 5the end be free of any oxide layers (to mm length tubular segment of ansupport welding arc initiation), that irradiated fuel rod from the H.B.the ends be faced orthogonal to the Robinson plant. a technical evalua- axis of the segment, and that the end tion was initiated and is ongoing tobe free of any burrs or other features evaluate chemical dissolution of largerwhich may inhibit the installation of segments within HFEF. This evaluationnew endcaps. The approach selected encompasses the impacts to both thewas to use the available remotized facility and other programs to accom- 3-axis end-mill in the HFEF hot cell. modate a larger acid bath dissolutionHowever, the machining operations system, and the necessary equip- to remove the oxide layer require the ment and/or facility changes neededinstallation of a 4th rotation axis. In to accommodate the operation. Athis case the fuel segment would be specific example is the evaluation ofplaced into a rotating stage so that the the vaporized fumes of nitric acid 16 2020|AFC ACCOMPLISHMENTS'