Extension Wire for High Temperature Irradiation Resistant Thermocouples

Journal Article · Tue Apr 01 04:00:00 EDT 2008 · Measurement Science and Technology

DOI:https://doi.org/10.1088/0957-0233/19/4/045206· OSTI ID:932248

Daw, J E; Rempe, J L; Knudson, D L; Wilkins, S C; Crepeau, J C

In an effort to reduce production costs for the doped molybdenum/niobium alloy High Temperature Irradiation Resistant Thermocouples (HTIR-TCs) recently developed by the Idaho National Laboratory (INL), a series of evaluations were completed to identify an optimum compensating extension cable. Results indicate that of those combinations tested, two inexpensive, commercially-available copper nickel alloy wires approximate the low temperature (0 to 500oC) thermoelectric output of KW-Mo versus Nb-1%Zr in HTIR-TCs. For lower temperatures (0 to 150oC), which is the region where soft extension cable is most often used, results indicate that the thermocouple emf is best replicated by the Cu-3.5%Ni versus Cu-5%Ni combination (measured emfs were within 4% at 100 and 150oC). At higher temperatures (300 to 500oC), data suggest that the Cu-5%Ni versus Cu-10%Ni combination may yield data closer to that obtained with KW-Mo versus Nb-1%Zr wires (measured emfs were within 8%). Further, interpolation of test results suggest that a combination containing a negative thermoelement with slightly lower nickel content, such as Cu-5%Ni versus Cu-9%Ni, may yield more representative data if extension cable is needed for these higher temperatures.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - NE
• DOE Contract Number: AC07-99ID13727
• OSTI ID: 932248
• Report Number(s): INL/JOU-07-13352
• Journal Information: Measurement Science and Technology, Journal Name: Measurement Science and Technology Journal Issue: 4 Vol. 19; ISSN 0957-0233; ISSN MSTCEP
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
47 OTHER INSTRUMENTATION
ALLOYS
CABLES
COPPER
High temperature Instrumentation
INTERPOLATION
IRRADIATION
In-pile Instrumentation
NICKEL
NICKEL ALLOYS
PRODUCTION
THERMOCOUPLES
Thermocouples