Nuclear reactor with integral heat exchangers

Nuclear reactor having integral heat exchangers comprising, in a vessel (1) containing liquid sodium, constituting the primary circuit in which the core (5) of said reactor is immersed, said core comprising fuel assemblies (6), supported by a horizontal support (3-4) bearing on the lower part of said vessel (1), at least two intermediate heat exchangers (35) which enable heating of secondary liquid sodium using the liquid sodium contained in said vessel (1) or primary liquid sodium, said heat exchangers being generally of an elongated shape and being each connected to a circuit for transporting said secondary liquid sodium between said intermediate heat excharger and a vapor generator for producing water vapor by employing the heat transported by said secondary liquid sodium, the vessel (1) of said reactor being closed by means of a horizontal slab (8) having openings one (10) of which, of large diameter and arranged above the core (5), is equipped with a platform (15) which is mounted so as to be rotatable about a vertical axis, referred to as the large rotating stopper, carrying the unit for control of said reactor and a device for handling the fuel assemblies, said intermediate heat exchangers (35) which are entirely enclosed within the vessel (1) being connected to said secondary sodium circuit by conduits (50) which pass through the slab closing of the reactor, said intermediate heat exchangers (35) which are arranged vertically, having their lower parts bearing on a support (3) of the core (5) at the periphery of the latter, said large rotating stopper (15) having an opening (53) of a size which is comparable to the dimensions of the cross-section of said intermediate heat exchangers (35), located at a distance from the axis of rotation of said rotating stopper, which makes it possible to bring this opening sequentially into vertical alignment with each one of the heat exchangers (35), by rotating said stopper (15).