Abstract: The cooling device comprises a heat exchanger (7) immersed in the hot header (4) of the nuclear reactor vessel, a substantially vertical tubular conduit (14) passing through the stepped wall (2) vertically below the exchanger (7), a bell (16) fixed under the exchanger (7) in the extension of its lower part and a mechanism for compressing inert gas and relieving pressure in the internal space of the bell (16). The inert gas compressed in the bell (16) enables the liquid metal in the hot header (4) to be completely separated from the liquid metal in the cold header (5). When the pressure in the bell (16) is relieved, the outlets (10) for the cooled liquid metal in the exchanger (7) are brought into communication with the cold header (5) through the bell (16) and the conduit (14).

Abstract: A device for providing protection against heat and radiation for an intermediate heat exchanger immersed in the vessel of a nuclear reactor. In its upper part, the exchanger has an inner sleeve (8a) inside which a liquid metal circulates, and an outer sleeve (8b), these sleeves being joined by a Y-shaped connector (25). A peripheral space is provided around the outer sleeve (8b), inside the passage (3) through the slab (2) covering the reactor vessel. The protection device comprises a sleeve (27) fixed under the flange (18) and carrying, in its lower part, a solid piece (30) occupying the greater part of the peripheral space around the sleeve (8b). In its upper part, under the flange (18), the sleeve (27) carries a heat insulation means (32) of annular shape. The Y-shaped connector (25) is located in the central part of the sleeve (27), between the solid piece (30) and the heat insulation means (32). The invention is applicable, in particular, to fast neutron nuclear reactors cooled by liquid sodium.

Abstract: A junction device between the delivery duct of a primary pump and a duct joined to the core support of a liquid metal cooled fast neutron nuclear reactor comprises a frusto-conical sleeve (6) widening out towards the inlet (2) of the duct joined to the core support, a connecting member (7) joined to the sleeve (6), a sealing device (18) interposed between the outlet end of the sleeve (6) and the inlet (2) of the duct joined to the core support, and an elastic means (6) interposed between the outlet end of the sleeve (6) and a support member joined to the core support. In its central portion the connecting member (7) carries the movable portion (14) of an articulated connection element the fixed portion (16) of which is carried by the pump. On its periphery this member (7) is connected sealingly and articulatedly to the delivery duct of the pump at the level of a spherical surface (9).