Framatome Gmbh

Cogema, Inc.

Areva Np Gmbh

Compagnie Generale Des Matieres Nucleaires

Pascal Burfin

Michel Bonnamour

Jean-Claude Leroux

Mingmin Ren

Jürgen Stabel-Weinheimer

Roland Mayet

Gilles Margier

Georges Masuy

A grid () for supporting nuclear fuel pencils () for a nuclear fuel assembly () comprising a peripheral belt (), the peripheral belt () comprising on at least one of its edges () guide fins () is disclosed. The edge () of the peripheral belt () has between the adjacent guide fins () recesses () towards the inside of the grid (). The invention is applicable, for example, to pressurized water reactors.

Rod spacer grid for a nuclear fuel assembly, and a corresponding assembly

Nuclear fuel assembly with an upper cap

The fuel assembly includes an arrangement for quickly fixing the guide thimble into an opening passing through the adaptor plate of a dismountable nozzle of the assembly. This arrangement includes at least two bearing stops inside the opening of the nozzle, a bearing sleeve integral with the end of the guide thimble and a locking ring which includes stops for bearing on bearing surfaces of the stops inside the opening of the nozzle and deformable elastic parts capable of being accommodated in cavities of the opening of the adaptor plate or of the bearing sleeve, in order to place the ring in a position in which the guide thimble is locked or unlocked. The sleeve includes a rim for bearing on a bearing surface of the adaptor plate at the periphery of the opening.

Dismountable fuel assembly of a nuclear reactor cooled by light water

The control cluster has a spider constituted by a hub connectable to a drive shaft. Fins radiate from a bottom portion of the hub and provided with vertical fingers distributed in a regular array. It also includes rods provided with plugs that are releasably fixed to the fingers. The fins, their fingers, and at least the bottom portion of the hub constituting a single-piece part obtained by molding or by electro-machining.

Nuclear reactor control cluster having removable rods

Each of the square top nozzles (26) of the fuel assemblies of the core includes four locating openings (40) in the vicinity of the vertices of the nozzle. The set of locating pins (35) of the upper core plate (32) includes four pins at each of the positions of fuel assemblies which are intended to be engaged in the four openings (40) of the top nozzle (26). The locating openings (40) of the nozzle may consist of the internal bores of sleeves (36) which are fixed on the nozzle in an axial arrangement and holds the spring leaves (38) of the nozzle. The locating openings may also be machined inside four bosses, projecting at the upper part of the assembly, and each arranged in one corner of the assembly.

Core of a pressurized water nuclear reactor and top nozzle of a fuel

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Saint-Genis-les-Ollieres, France

Pascal Burfin