Aging of nuclear plant resistance temperature detectors

Technical Report · Fri Jun 01 04:00:00 EDT 1990

DOI:https://doi.org/10.2172/7072109· OSTI ID:7072109

Hashemian, H M; Beverly, D D; Mitchell, D W; Petersen, K M ^[1]

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1. Analysis and Measurement Services Corp., Knoxville, TN (USA)

A comprehensive research and development project was performed over a 30 month period to quantify the effects of normal aging on performance of nuclear safety-related Resistance Temperature Detectors (RTDs). The work involved laboratory testing of 72 nuclear grade RTD elements representing several from each of the four US manufacturers. The limit for the initial accuracy of these RTDs was established and a procedure for performing precise calibration was developed. Experimental aging of 30 of these RTDs in simulated reactor conditions resulted in five failures and six major calibration shifts. Two failures occurred in thermal aging, one in vibration aging, one in humidity aging, and one in thermal cycling. The remaining 19 RTDs performed well during the aging test, maintaining a drift band of {plus minus}0.2{degree}C. The project did not reveal any unanticipated or major systematic aging problem in the performance of the RTDs tested. The nuclear industry's practice for verifying adequate RTD accuracy and response time is to perform on-line cross calibration and Loop Current Step Response tests at least once every fuel cycle. In light of the data obtained throughout this study, this approach is reasonable for management of aging of RTDs which do not have any major design, fabrication, or installation deficiencies. RTDs that consistently maintain a suitable calibration and response time, as determined by periodic testing, can be used in the plant for their qualified life as specified by the manufacturer. The manufacturer's specification for qualified life of nuclear grade RTDs typically range from 10 to 40 years depending on the manufacturer and the conditions in which the RTDs are used. 11 refs., 67 figs., 53 tabs.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (USA). Div. of Engineering; Analysis and Measurement Services Corp., Knoxville, TN (USA)
• Sponsoring Organization: NRC
• OSTI ID: 7072109
• Report Number(s): NUREG/CR-5560; ON: TI90013885
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200* -- Nuclear Reactor Technology-- Components & Accessories
ACCURACY
AGING
CALIBRATION
DATA
ENERGY TRANSFER
EXPERIMENTAL DATA
HEAT TRANSFER
INFORMATION
MANUFACTURERS
MEASURING INSTRUMENTS
MONITORING
NUCLEAR FACILITIES
NUCLEAR POWER PLANTS
NUMERICAL DATA
POWER PLANTS
SPECIFICATIONS
TEMPERATURE MONITORING
THERMAL DEGRADATION
THERMAL POWER PLANTS
THERMOMETERS