Commissariat a L'energie Atomique

Framatome Gmbh

Framatome & Cie.

Jacques Baujat

Guy Desfontaines

Gerard Chevereau

Alain Heuze

Roger Aubert

Rene Feurgard

Internal equipments suitable for use in a nuclear reactor comprise a lower plate provided with openings for the coolant leaving the core, an upper plate, support columns connecting the plates together and guides for the vertically movable control clusters. Each guide has an upper section fixed to the upper plate and a lower section extending between the upper and lower plates. The lower section (32) comprises a base bearing on a frusto-conical seat fast with the lower plate and is subjected to the action of resilient means exerting a force pressing the base on the seat.

Nuclear reactor internals with cluster guides

A nuclear reactor has a pressure resistant vertical vessel with inlet and outlet pipes situated at the same horizontal level. It also includes internals having a barrel supporting the core and defining with the vessel a down flow path for the coolant from the inlet pipes towards a space under the core and upper internals defining a flow path for the coolant leaving the core, above this latter, and flowing towards the outlet pipes. The upper internals include dividing walls defining circumferentially distributed volumes located at the common level of the pipes and each over a different angular sector. Some volumes belong to the initial part of the downgoing coolant path and the others force part at least of the coolant leaving the core to follow a path which is successively directed upwardly then curving towards the outlet pipes. The invention is particularly suitable for use in pressurized water reactors.

Nuclear reactor with flow guidance in the upper internals

Device for elimination of vibrations of a valve for decompression of an enclosure containing a fluid under pressure, comprising a lever articulated on the valve body in two parts. The first part is integrally fixed to a spindle mounted to rotate in the valve body. This part comprises a rocker arm and its end opposite the rocker arm is connected to the valve stem. The second part is connected to the moveable armature of an electromagnet and comprises a bearing surface for the tappet. The two parts of the lever are connected through the intermediary of a friction coupling. Movements of the valve beyond the position of locking by the electromagnet are damped by the friction coupling. The invention is applicable in particular to a decompression valve in a pressurized water nuclear reactor.

Device for elimination of vibrations of a valve for decompression of an

A cylindrical shell or so-called reactor core basket is fitted with a coaxial and cylindrical bearing ring which is joined to a top flange of the core basket by means of radial struts and rests on an internal annular shoulder of the reactor vessel. Passageways between the bearing ring and the struts accommodate instruments for nondestructive testing of welded joints, the instruments being guided and displaced over the external face of the core basket in order to inspect the internal face of the reactor vessel without any need to remove reactor internals.

Internal structure for a nuclear reactor vessel

The device comprises a cradle constituted by a plurality of identical and coplanar half-bridges each formed by two identical and parallel main beams. The half-bridges are carried on a vertical supporting element at one extremity which is constituted by one of the extremities of the beams and are rigidly coupled together at the other extremity. The cradle is provided with structural elements which are rigidly fixed to the beams and to which the pressure vessel and steam generators are attached.

Growing community of inventors

Versailles, France

Jacques Baujat