Abstract: A sealing device comprising a supporting assembly (9) containing sealing members (16) supporting the instrument column (5), and an assembly (17, 18) for lifting the instrument column (5) in sealing engagement with the supporting members (16). The sealing members (16) supporting the instrument column (5) include a clamping ring (28) and at least one O-ring seal (29, 30). Axial movement of the instrument column (5) enables clamping of the inner seal (30) via the clamping ring (28). When axial movement of the instrument column (5) is restricted, the seals may be clamped by means of a suitably sized clamping ring (28).

Abstract: System, device and process for inspection of a thermal neutron absorption wall. The device comprises a fast neutron source and an arrangement for thermal neutron detection comprising at least one pair of oblong, substantially parallel thermal neutron detectors placed side by side, and substantially perpendicular to the direction of displacement of the device along the neutron absorption wall.

Abstract: The instrumentation column (5) comes to bear via a bearing surface and a sealing gasket (16) inside a bearing element including a tubular length (8) and a closure cover (11) joined together by screwed assembly means. The tubular length (8) and the cover (11) each include a bearing surface (33a, 34) which is symmetrical of revolution about the axis of the instrumentation column (5). The bearing surface (33a) of the cover (11) and the bearing surface (34) of the tubular length (8) between them, through direct metal-to-metal contact, provide sealing against the pressurized water of the reactor.

Abstract: The detection device includes at least one thermocouple (10) arranged aligned with the bottom head of the vessel of the nuclear reactor, having a first branch (9) made of a first metallic material and at least one second branch (11) made of a second metallic material, different from the first material, welded to a point on the first branch constituting a hot junction of the thermocouple (10). The first branch (9) of the thermocouple has the form of an elongate hollow section. The device furthermore includes means for analyzing the measurements taken by the thermocouples (10).

Abstract: A device for treating cerebral lesions by gamma radiation, comprising an approximately semi-spherical source-collimator assembly having a large number of gamma ray sources associated with channels directed to the same focal point. Each gamma ray source is associated with a group of channels arranged in the manner of a cone, the apex of which is at the focal point.