Patent Number: 043269206
Section: claims

1. In a pool type nuclear reactor including a number of reactor components located within a vertically extending cavity which is located under a reactor deck arrangement and which is defined by a circumferential cavity wall assembly, the improvement comprising a reactor vessel separated and distinct from said deck arrangement and said cavity wall assembly for containing said reactor components, said vessel including a main body located within said cavity and an upper circumferential rim formed by a vertically exteded support flange located and interlocked between said deck arrangement and an upper section of said wall assembly, whereby to form a support means for said vessel body within said cavity and said deck arrangement above said vessel body, said support means including a first downwardly directed, circumferential shoulder extending around and forming part of said support flange, a first upwardly directed, circumferential shoulder extending around and forming part of said cavity wall assembly said first upwardly directed shoulder cooperating with said first downwardly directed shoulder for supporting said vessel within said cavity, a second downwardly directed circumferential shoulder extending around and forming part of said deck arrangement, a second upwardly directed, circumferential shoulder extending around and forming part of said support flange on the opposite side of and above said first downwardly directed shoulder but below the top of said flange, said second upwardly directed shoulder cooperating with said second downwardly directed shoulder for supporting said deck arrangement over the main body of said vessel and means for sealing between said support flange and both said deck arrangement and said wall assembly, said sealing means displaying at least a limited degree of compliance whereby to accomodate thermal displacement. 2. The improvement according to claim 1 wherein the main body of said reactor vessel and said support flange are both constructed of stainless steel. 3. The improvement according to claim 2 wherein said main body and support flange are formed as a single unit. 4. The improvement according to claim 4 including a slide plate located between at least one of said pair of cooperating shoulders in order to allow for differential thermal displacement between said one pair of shoulders. 5. The improvement according to claim 4 including a slide plate located between each pair of said cooperating shoulders. 6. The improvement according to claim 1 including shear pins extending between said deck arrangement and flange support and between the latter and said wall assembly for resisting seismic forces. 7. The improvement according to claim 6 wherein the shear pins are aligned with said arrangement, flange, and assembly so as not to restrain differential thermal expansion between these latter components. 8. The improvement according to claim 1 including a compliant ring located between said first shoulders in order to allow for differential thermal displacement. 9. In a pool type nuclear reactor including a number of reactor components located within a vertically extending cavity which is located under a reactor deck arrangement and which is defined by a circumferential cavity wall assembly, the improvement comprising a reactor vessel separate and distinct from said deck arrangement and said cavity wall assembly for containing said reactor components, said vessel including a stainless steel main body located within said cavity, and an upper circumferential rim forming a support flange located between said deck arrangement and an upper section of said cavity wall assembly, a first downwardly directed, circumferential shoulder extending around and forming part of said support flange, a first upwardly directed, circumferential shoulder extending around and forming part of said wall assembly, said upwardly directed shoulder cooperating with said downwardly directed shoulder for supporting said vessel within said cavity, a second downwardly directed, circumferential shoulder extending around and forming part of said deck arrangement, a second upwardly directed, circumferential shoulder extending around and forming part of said support flange on the opposite side of and above said first downwardly directed shoulder but below the top of said flange, said second upwardly directed shoulder cooperating with said second downwardly directed shoulder cooperating with said second downwardly directed shoulder for supporting said deck arrangement over said vessel body, means for sealing between said support flange and both said deck arrangement and said wall assembly, said sealing means displaying at least a limited degree of compliance in order to accomodate thermal displacement, and means located between said first and second shoulders in order to allow for differential thermal displacement between said shoulders, said last mentioned means including a slide plate between said first shoulders and a slide plate between said second shoulders.