NDTsi 2001 Session: Advances in Non-Ultrasonic NDE Methods
RCCA Rod Wear Inspection System Using Rotating Ferrite ECT
A. Shimmura, A. Hata, Y. Harada, T. Emori, Nuclear Engineering, Japan; F. Hardy, G. Lafontaine, R/D TECH, Canada
ABSTRACT
RCCA (Rod Cluster Control Assembly) is an essential component for the PWR plant, which control the reactor. In some cases, RCCA rod wear may occur during long-term plant operation due to fretting between RCCA rods and guide tubes or fuel assemblies. NEL (Japan) have developed an inspection system, which enables on-site inspection of all the RCCA rods wear, in cooperation with R/D Tech (Canada). Taking into account the necessity to complete inspections within a limited period of time, we have developed a wear inspection system for RCCA rods using mechanically rotating ferrite type ECT base on the principle of eddy current testing. This inspection system, compared with a conventional inspection system using array coils, can test a larger number of rods at a higher speed without rotating a RCCA handling tool. One run upward and downward along the RCCA enables inspections of all the rods including the full length of the rod cladding from the upper end weld to the lower end weld. In addition, a newly developed analysis software enables quantitative evaluation of axial location, circumferential location and depth of wear. Performance tests of this inspection system were conducted using mock-up samples with wear and depth evaluation curves were developed.
Publication Source: 3nd International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components, November 14-16, 2001, Seville Spain. Publisher: Tecnatom s.a. - [Homepage]
