Measurement of deformation of FBR fuel assembly wrapper tube by an innovative technique

Sasaki, Shinji  ; Abe, Kazuyuki; Nagamine, Tsuyoshi

An innovative technique to measure the deformation of irradiated wrapper tube of FBR fuel assembly was developed, and installed in the hot cell of the Fuels Monitoring Facility in JAEA. In order to confirm the performance of this instrument, a number of measurements were carried out in the wrapper tubes irradiated to high burnup in the experimental fast reactor Joyo. In the instrument used until now, only three face to face distances in the hexagonal wrapper tube have been measured along the axial direction. On the other hand, in the instrument developed in this technique the face to face distances could be continuously measured along the lateral direction in the outer surfaces of wrapper tube. Using data obtained by this technique, the detailed analyses of deformation can be done throughout a whole wrapper tube.