Patent Number: 052572951
Section: summary

TECHNICAL FIELD The present invention relates to a core baffling device for nuclear reactors, intended to occupy the annular space between the prismatic shaped core of the reactor and a cylindrical core casing and comprising vertical baffling plates surrounding the core and reinforcing elements placed between the baffling plates and the casing. BACKGROUND OF THE INVENTION Numerous baffling devices of the above type are already known. They force the coolant, which arrives under a core support plate through the annular gap which separates the casing from a pressure vessel, to flow through the fuel assemblies forming the core. In present day pressurized water reactors for example, the baffling device occupies the gap between the prismatic shape, with right angle facets, and the cylindrical casing. In most baffling devices existing at the present time, the vertical baffling plates or "baffles" are held in position by horizontal plates, called formers. The mounting of such a baffling device, which must comply with strict dimensional requirements and withstand the temperature, radiation and differential pressure conditions prevailing in the vicinity of the core, raises problems which are only partially solved at the present time. In particular, the assembly of the plates and of the formers in the reactor, using screws whose number largely exceeds one thousand, is long and difficult. The breakage of a screw opens a gap, and so a leak jet harmful for the fuel rods of the assemblies placed in the vicinity. SUMMARY OF THE INVENTION An object of the present invention is to provide an improved baffling device. It is a more specific object to be carried out on the spot, inside the reactor vessel, and to increase reliability. For this, there is provided a baffling device comprising panels distributed in horizontal rows and vertical columns, all panels of the same row being identical and having vertical baffling plates welded together, fast with horizontal and vertical mutually crossing reinforcements for bearing on the casing and with vertical tubes, the tubes of a same column forming, by stacking thereof, posts resting on a core support plate; and solid vertical keys connecting together the panels of the different columns and fixed to the casing. In a nuclear reactor comprising square cross-section fuel assemblies, the panels will generally be distributed in three rows and four columns. The invention will be better understood from the following description of a particular embodiment of the invention, given by way of non-limiting example. The description refers to the accompanying drawings.