Design calculations for eddy-current displacement sensors for Chalk River Nuclear Laboratories (AECL)

Technical Report · Wed Feb 01 00:00:00 EST 1978

DOI:https://doi.org/10.2172/5148219· OSTI ID:5148219

Dodd, C. V.

An analysis has been made of four different types of eddy-current sensors to measure the displacement of a fuel tube contained coaxially in a pressure tube. The first sensor consisted of a bifilar coil encircling the pressure tube. Its sensitivity was inadequate. The second sensor was bifilar coil inside the pressure tube and encircling the fuel tube. This coil had adequate sensitivity to the swelling of the fuel cladding but could not measure its bowing. The third sensor consisted of an array of eight pancake coils spaced around the fuel cladding and inside the pressure tube. This sensor could measure both bowing and swelling of the cladding independently, but was subject to fairly large drifts. The fourth sensor used eight pancake coils that measured the distance to spring-loaded feelers that directly contacted the fuel cladding. This was the most sensitive device and exhibited the smallest drift. None of the sensors could measure the temperature of the fuel cladding because the temperature was not a single valued function of the resistivity over the specified range of 20 to 1200/sup 0/C.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5148219
• Report Number(s): ORNL/TM-6160; TRN: 78-007387
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
DISPLACEMENT GAGES
PERFORMANCE TESTING
FUEL ELEMENTS
PRESSURE TUBE REACTORS
EDDY CURRENT TESTING
SPECIFICATIONS
ELECTROMAGNETIC TESTING
MATERIALS TESTING
MEASURING INSTRUMENTS
NONDESTRUCTIVE TESTING
REACTOR COMPONENTS
REACTORS
TESTING
210400* - Power Reactors
Nonbreeding
Otherwise Moderated or Unmoderated