Patent Number: 055880312
Section: summary

FIELD OF THE INVENTION The present invention relates generally to a core shroud that is contained within a reactor vessel of a nuclear power plant and, more particularly, to an apparatus for reinforcing the core shroud in the event of cracking or other conditions of similar magnitude. BACKGROUND OF THE RELATED ART In a commercial nuclear reactor, heat, from which steam and ultimately electricity are generated, is produced by fissioning of a fissible material, such as enriched uranium, contained in a reactor core which is, in turn, contained within a reactor vessel. The reactor vessel includes a flanged, dish shaped closure head bolted atop a flanged, generally cylindrical shaped reactor body; the reactor vessel is entirely contained within a containment building for containing any unlikely radiation leakage within the containment building should an accident occur. A generally cylindrical shaped core shroud extends coaxially inside the reactor vessel for creating an annulus between the reactor vessel and core shroud. The core shroud typically includes an upper portion with a slightly greater diameter than its middle portion, and its middle portion with a slightly greater diameter than its lower portion. Although the presently known and utilized core shroud is satisfactory, it is not without drawbacks. In the area where its upper, middle and lower portions are respectively joined together, there is a tendency for stress corrosion cracking. Consequently, a need exists for a core shroud repair which is operable for reinforcing the core shroud in the event of stress corrosion cracking or events of similar magnitude. SUMMARY OF THE INVENTION The present invention provides an improvement designed to satisfy the aforementioned needs. Particularly, the present invention is directed to an apparatus, which reinforces a core shroud that is contained within a reactor vessel, operable in the event of cracking or events of similar magnitude in the core shroud, the apparatus comprising: (a) a reactor vessel wall positioned surrounding the shroud; (b) a beam attached to the shroud for absorbing the forces generated in the shroud; and (c) a radial support positioned between said beam and said reactor vessel wall for transmitting any forces absorbed by said beam to said reactor vessel wall which, in effect, reduces the loads in said beam and also maintains generally uniform distribution of the loads absorbed by said beam for allowing said beam to absorb the generated forces. It is an object of the present invention to provide a device for reinforcing the core shroud in the event of cracking. It is a feature of the present invention to provide a beam extending generally vertically on the shroud and a radially extending support attached thereto and resting against a reactor vessel wall for transmitting the forces created in the core shroud by the cracking to the reactor vessel wall. It is an advantage of the present invention to provide the vertically extending beam in a configuration which is easily attached to the core shroud.