Abstract: Two carriages which can be displaced independently of each other in vertical translational motion are guided by means of slideways secured to a rotatable vertical body, the upper end of which passes through the rotating shield plug of the reactor. Each carriage has a horizontal arm and grab for handling fuel assemblies, the arms being maintained parallel to each other.

Abstract: Two guide ramps for the transfer of fuel assemblies in sliding motion between the reactor core and an external storage container are surmounted by a lock-chamber in which two pivotally suspended rectilinear rail sections carried by a revolving unit form guide ramp extensions. Each rail section has a lever extension in cooperating relation with a rocking system for displaying the rail section in swinging motion from an inclined position in the line of extenson of one of the guide ramps to the vertical position and conversely.

Abstract: A device for protecting the dome of a nuclear reactor containment vessel against the upward displacement of the concrete shield slab of said reactor and the resultant effects of tilting of an equipment unit mounted on the shield slab at the periphery of said slab, wherein said device comprises:--means for separating the equipment unit into two sections consisting of an upper section and a lower section, said lower section being rigidly fixed to said shield slab and said means being actuated by the upward displacement of said slab,--a system for vertical rectilinear guiding of said upper section within the containment vessel,--rigid mechanical components which provide a coupling between the aforesaid upper and lower sections of the equipment unit and exert on said upper section under the action of the tilting motion of said lower section a thrust which causes the upward displacement of said upper section.