Abstract: The clogging indicator makes it possible to continuously measure the purity of sodium circulating in the circuits of a fast neutron reactor without requiring the dismantling or completely changing the indicator should the measuring section becomes clogged. The clogging indicator essentially includes a bypass pipe comprising one coaxial external section (8) and one coaxial internal section (9). A measuring head (10) is mounted and able to move between these two sections and is mainly composed of at least one thermoelement (24) and one mobile grid (22) causing the measuring section to vary and thus the measured flow so as to favor uncloggings and the dissolving of any impurities crystallized during the measurements. This unit is completed by the other main elements of the clogging indicator in an elongated longitudinal body and surrounded by a thermic exchanger (11) for cooling the sodium.

Abstract: Apparatus for the production of steam by heat-exchange between a heat-transfer liquid metal and feed-water, comprising an envelope (1) containing a tube bundle (8) which occupies only part of the internal volume of the envelope with the bundle (8) in which the feed water is passed in. At least two superposed compartments (18, 28), in communication with the internal volume of the envelope (1) by their lower part, are located inside the envelope (1). Each of the compartments (18, 28) communicates with the compartment located thereabove by means of a first tube (23), and with the compartment located therebelow by means of a second tube (21). The compartment (28a) located at the lowest level is fed with inert gas through the establishment of liquid/inert gas interfaces in each of the compartments (18, 28). The invention applies particularly to the steam generators of fast neutron nuclear reactors, in which it is desired to avoid the harmful effects of pressure waves in case of a sodium/water reaction.

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).

Abstract: Nuclear reactor exchanger which assures the transfer of heat between two streams of coolant sodium. It includes an outlet connector which channels coolant sodium leaving a bundle of exchanger tubes traversed on the inside by the sodium and immersed externally in coolant sodium, and an inner tubular jacket forming a surface of revolution about a vertical axis and an outer tubular jacket. The wall of the inner jacket has a folded portion distinguished by at least one flank in the form of a crown.

Abstract: This invention relates to a bearing system for supporting a nuclear reactor vessel of the kind which is suspended from the reactor closure slab.The bearing system comprises a ring connected at one end to a collar and at the other end to two collars. The collar connected to the bottom end of the ring forms the top part of the vessel to be supported while the other two collars fit into the slab at two separate places. The ring and collars are disposed in an annular space formed in the slab and dividing it into two parts, i.e. a central part and a peripheral part surrounding the central part of the slab.