b'Fuel Rod Refabrication CapabilityPrincipal Investigators: Jason SchulthessTeam Members/ Collaborators: Spencer Parker, Evans Chambers, Jordan Argyle, Kim Davies, Justin Yarrington, Clayton Turner, Cad Christensen, James Chandler, John Stanek, Mark Cole, and Mike BybeeNew refabrication andI rradiated fuel rod refabricationends to make space for new end caps, is a crucial enabling capabilityattaching and welding in place new experiment assemblythat bridges between base reactorend caps, and pressurizing and seal capability to supportirradiation and subsequent experimen- welding the new rods, followed by follow on irradiation andtation and/or re-irradiation. It is key toleak check inspection, which are then out of pile testing ofperforming meaningful research andavailable for follow on irradiation or previously irradiated fuel. development (R&D) on fuels with anyout of pile testing.level of burnup, especially at the Tran- The basic refabrication welding sient Reactor Test (TREAT) Facility andsystems have been designed to provide opens the door to R&D for materialsmaximum flexibility and reliability tested in commercial nuclear powerto perform the three necessary welds. plants. Refabrication allows accessTwo circumferential welds to attach to fuel at any point in its lifetime,the end caps, and one seal weld to allowing opportunity to apply instru- ensure hermeticity of the rodlet. All mentation and perform experiments tothree welds are performed using measure performance under a varietycommercially established micro-of specified conditions. Secondly, theTungsten Inert Gas (TIG) welding ability to repackage previously irradi- methodology. The circumferential ated fuel into experiment vehicles is anwelds are performed using a custom enabling capability that ensures experi- designed welding lathe, which holds ments are instrumented and containthe welding torch in a single position desired boundary conditions forand rotates the rodlet, which provides experiment objectives. Measurementsthe most consistent welding on these on high burnup fuels are impractical,materials. The lathe system further if not impossible, without refabricationincorporates an automated variable and experiment preparation capability. voltage controller, which supports Project Description: consistent welds if the rods are found A fuel refabrication system andto be non-circular (e.g., elliptical). process has been designed, con- The seal welding system also utilizes structed, installed, and demonstratedmicro-TIG methodology and encap-in the Hot Fuel Examination Facilitysulates the rodlet in a pressurized (HFEF) hot cell to enable basic fuelchamber capable of pressurizing the rod refabrication. The basic refabrica- rodlet from 500 psi to 2250 psi to tion capability includes segmentingallow for experiments to be conducted full length fuel rods, defueling thewith variable rodlet internal pressures. 140 2021|AFC ACCOMPLISHMENTS'