Abstract: Apparatus for charging a nuclear reactor disposed at the bottom of a pool. The reactor is constituted by a plurality of tiers of combustible assemblies having different stages of enrichment, each assembly having combustible rods and an auxiliary cluster associated with the particular tier of the assembly. The apparatus comprises a rolling bridge supported for movement in a plane above the pool, and carrying a turnable platform which supports a plurality of vertical telescopic manipulation arms arranged in angular spaced relation thereon. Each arm carries a respective grappling unit for respectively engaging a complete combustible assembly or at least one type of auxiliary cluster. The auxiliary clusters may include control clusters, sealing clusters and poison consumable clusters.

Abstract: In a nuclear reactor, a drainage channel for the safety injection and spray circuits of the reactor is arranged in the bottom of the annular gap between two substantially vertical walls surrounding the pressure vessel of the reactor, the drainage channel comprising filter panels disposed vertically along each side of a central horizontal solid lower panel at the bottom of the annular gap and between two lateral horizontal solid upper panels so as to bound a central channel having vertical lateral filter walls communicating with two lateral chambers which communicate by substantially horizontal passages with a central collecting chamber disposed below the central lower panel and having an outlet for connection to the main intake of the safety circuit.

Abstract: In the detection of cracks in fuel element units using a crack detection cell, the cell includes heating means which are energized to heat the unit. The heating means form part of a pocket in which the unit is received, the pocket being received in a double-walled chamber which can be thermally insulated from the surrounding medium.

Abstract: Apparatus for visually examining the fuel rods of an assembly of fuel rods immersed in the tank of a nuclear reactor or in a deactivation tank, comprises an endoscope including a prism and an optical system of stabilized glass, and at least one arm supporting a mirror facing the prism and inclined relative to the plane defined by the axis of the tube of the endoscope and the arm, the thickness of the arm-mirror assembly being less than the free space between the rods of the assembly. In use the apparatus is mounted on a system of carriages which enable the apparatus to move in three perpendicular directions, the carriages being associated with rotatable means for supporting an assembly of rods to be examined.

Abstract: A device for use in positioning a member, e.g. an eddy-current probe, in each tube of a regular array of tubes supported by a tube plate, e.g.