Abstract: A fast neutron nuclear reactor having a vessel filled with liquid metal and sealed in its upper part by a box slab having a central opening in which is placed a plug-cover-core overhanging the core of the reactor. The central opening is surmounted by a cell containing the handling and storage mechanism for the plug-cover-core and a mechanism for handling the assemblies. The latter can be moved on annular rails and can be collapsed against the wall of the cell, in order to permit the manipulation of the plug-cover-core. A radial passage connects the cell to a transfer station.

Abstract: Heat exchanger of a nuclear reactor, whose vessel is sealed by a slab, the exchanger being of the type which has within a vertically axed outer ferrule a plurality of heat exchange modules with substantially straight tubes, each of the said modules having a secondary fluid inlet chamber and a secondary fluid outlet chamber and means for introducing and removing the primary fluid with respect to the exchange modules, wherein it comprises a base plate peripherally fixed to the said outer ferrule, means for supporting the outer ferrule by the slab, supporting ferrules for the modules, each ferrule traversing the base plate and being connected on the one hand to the upper end of the module and on the other to the said base plate, a plurality of pipes for the supply and removal of the secondary fluid sealingly traversing the base plate, a supply manifold and a discharge manifold for the secondary fluid positioned within the outer ferrule above the base plate, said manifolds being respectively connected to the supp

Abstract: Intermediate exchanger comprising a vertically axed cylindrical internal ferrule, an external ferrule coaxial to the internal ferrule, two plates with annular horizontal tubes located in the vicinity of the upper and lower ends of said ferrules, a bundle of straight tubes extending between the tubed plates in the form of cylindrical layers coaxial to the ferrules, said layers being mutually reinforced by transverse belts formed by horizontal bands carrying hollow members located between the tubes of the layers and in contact with the latter, collectors for the admission and discharge of the secondary fluid circulating within the said tubes being respectively provided beneath the lower plate and above the upper plate, the inner ferrule forming a pipe for the supply of the secondary fluid to the admission collector, while the outer ferrule is upwardly extended by a pipe for the discharge of the same secondary fluid collected in the discharge collector after passing through the tubes, and inlet and outlet ports

Abstract: In a fast reactor constituted by an open-topped main vessel containing liquid metal coolant and an inner vessel mounted within the main vessel, a transverse skew wall forming an inner vessel extension is associated with a baffle which extends above the skew wall. A space formed between the baffle and the skew wall and containing a practically static volume constitutes a thermal shield between the hot liquid metal located within the inner vessel above the baffle and the cold liquid metal located between the inner vessel and the main vessel beneath the skew wall.

Abstract: Fast neutron nuclear reactor comprising on the inside a main vessel having a vertical axis suspended by its upper open part on a thick protective slab which seals a cavity surrounding said vessel, a volume of a liquid cooling metal and also positioned within said main vessel an inner vessel having a cylindrical wall containing the core of the reactor submerged beneath the liquid metal level, the intermediate space between the main vessel and the inner vessel having heat exchangers and pumps which pass below the level of the liquid metal, wherein the upper end of the inner vessel is covered by an inverted annular bell cap and is placed under the internal pressure of a neutral gas in order to prevent in normal operation direct communication between the hot liquid metal within the inner vessel and the cold liquid metal in the annular space between the main vessel and the inner vessel, said bell cap covering an auxiliary exchanger which externally surrounds the inner vessel in such a way that if there is a fault

Abstract: A cylindrical inner vessel containing the reactor core is placed coaxially within a main vessel. Heat exchangers are disposed within the annular space formed between the two vessels, each heat exchanger being delimited by an outer shell and a coaxial inner shell which surrounds a central feed duct having a vertical axis. The upper end of the annular space communicates with a flared end portion of the central duct through a first circular window formed in the inner shell. The lower end of the annular space communicates with the region located between the inner vessel and the main vessel through a second circular window formed in the outer shell.