An assessment of liquid-metal centrifugal pumps at three fast reactors
- Oak Ridge National Lab., TN (United States)
The results of an analysis using data reports submitted to the Centralized Reliability Data Organization (CREDO) to predict the onset of the wearout life period for large sodium centrifugal pumps is described. For CREDO data collection and analysis purposes, a mechanical pump'' includes the pumping unit, its driver, and the coupling between the two. Statistical data were compiled from event reports received from three fast reactors: the Experimental Breeder Reactor II (EBR-II) and the Fast Flux Test Facility (FFTF) in the US and the JOYO Experimental Fast Reactor operated by the Power Reactor and Nuclear Fuel Development Corporation of Japan. Cumulative event rates were calculated for the investigated pumps at each facility and for the entire population. For all pumps, the event rate was computed as 34.4 event/million operating hours with 5 and 95% one-sided confidence limits of 26.3 and 44.4 event/million operating hours, respectively. The cumulative event rates for EBR-II, FFTF, and JOYO were computed as 30.0, 32.4, and 40.6 event/million pump operating hours, respectively. Results from EBR-II indicate that there is a definite time-dependent relationship between event rates and pump age; the common event mode at EBR-II is pump binding or seizing due to the buildup of sodium deposits in the vicinity of the lower labyrinth seal. There is no indication from FFTF that the six centrifugal pumps have reached the end of their useful life; these pumps have been event free for their last 40,000 operating hours. Following a 50,000-h even-free operating period at JOYO, bearings in the secondary pumps required additional unscheduled maintenance. However, there is no indication that these pumps have entered into the wearout life period; more data are required to draw any such conclusion.
- OSTI ID:
- 5888778
- Journal Information:
- Nuclear Technology; (United States), Vol. 104:1; ISSN 0029-5450
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CENTRIFUGAL PUMPS
SERVICE LIFE
EBR-2 REACTOR
REACTOR COOLING SYSTEMS
FFTF REACTOR
JOYO REACTOR
BEARINGS
DATA ANALYSIS
FORECASTING
LIQUID METALS
OPERATION
REACTOR MAINTENANCE
RELIABILITY
SODIUM
ALKALI METALS
BREEDER REACTORS
COOLING SYSTEMS
ELEMENTS
ENERGY SYSTEMS
EPITHERMAL REACTORS
EXPERIMENTAL REACTORS
FAST REACTORS
FBR TYPE REACTORS
FLUIDS
LIFETIME
LIQUID METAL COOLED REACTORS
LIQUIDS
LMFBR TYPE REACTORS
MAINTENANCE
METALS
POWER REACTORS
PUMPS
REACTOR COMPONENTS
REACTORS
RESEARCH AND TEST REACTORS
RESEARCH REACTORS
SODIUM COOLED REACTORS
TEST REACTORS
220600* - Nuclear Reactor Technology- Research
Test & Experimental Reactors