Results of the PBF/LOFT Lead Rod Test Series

The PBF/LOFT Lead Rod (PBF/LLR) Test Series consisted of four sequential, nuclear blowdown experiments (Test LLR-3, LLR-5, LLR-4, and LLR-4A). The primary objective of the test series was to evaluate the extent of mechanical deformation that would be expected to occur to low pressure (0.1 MPa) light water reactor design fuel rods subjected to a series of nuclear blowdown tests, and to determine if subjecting deformed fuel rods to subsequent testing would result in rod failure. The extent of mechanical deformation (buckling, collapse, or waisting of the cladding) was evaluated by comparison of cladding temperatue versus system pressure response with out-of-pile experimental data and by posttest visual examinations and cladding diametral measurements