Abstract: The apparatus enables eddy current inspection of a metal tube having a thin layer on its outside face with magnetic or electrical characteristics that are different from those of the metal in-depth. The apparatus comprises a measurement head having a measurement coil (14) for surrounding the tube and means for powering the coil with voltage at high frequency, greater than 100 kHz, and for analyzing the impedance of the coil. The head contains a magnet (22) surrounding the coil and magnetic flux guides (24) on either side of the coil in the axial direction and co-operating with the magnet to constitute a magnetic circuit that creates a magnetic field whose maximum intensity lies inside the coil and close thereto.

Abstract: The apparatus for inspecting the rods of a cluster insertable in the core of a nuclear reactor comprises a body provided with sliding guide means for rods in m different orientations of the cluster, m being a submultiple of the number n of rods in the cluster, and a measurement jig carrying n/m heads (16) for eddy current examination and n/m probes (18) for ultrasound scanning placed on different guide paths. Each ultrasound probe (18) is constituted by an annular support surrounding a rod path and carrying a ring of individual transducers. The transducers are connected to a circuit for sequentially exciting the transducers in successive groups, causing the tube to be scanned circumferentially, and for electronic focusing towards the surface of a tube travelling on the path.