EROSION RESISTANCE OF SWAGED UP, FOLLOWING AN IN-REACTOR FUEL ROD CLADDING FAILURE

摘要

During a routine irradiation of a swaged UO2, 19-rod cluster fuel element (GEH-12-4) in an ETR facility, an unpremeditated cladding split occurred in one fuel rod. The failure occurred during the 24th day of full power operation at a maximum surface heat flux of ~ 600, 000 Btu/(hr)(sq ft). Inspection of the 1. 5 inch long split revealed that a maximum of 10 per cent of the exposed, sintered UO» had been eroded. This finding was particularly significant since the reactor was operated at full power for 15 hours after the defect was detected. Examination also revealed that no structural weakness, distortion, or corrosion was evident in the fuel rod bundle.