Patent Number: 051494957
Section: claims

1. A water rod, usable for containing water in a substantially interior position in a nuclear fuel rod bundle, the bundle having a plurality of lattice positions spaced at a predetermined lattice pitch, comprising: a hollow longitudinally extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy a predetermined number of the lattice positions of the bundle;  said cross-sectional interior region being configured to define two round-cornered, triangular regions continuously connected by a constricted region, said constricted region being defined by two inwardly extending longitudinal projections;  wherein said predetermined number is greater than four lattice positions and less than nine lattice positions; and  wherein said area of said cross-sectional region, said predetermined number, and said pitch define a water rod efficiency greater than about 0.7; and,  at least one projection on an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said sidewall, at least in a portion substantially adjacent to said projection, to permit passage of said projection over an obstruction when said water rod is axially moved proximate to said obstruction.  a hollow longitudinally-extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy a predetermined number of lattice positions of the bundle;  said cross-sectional interior region being configured to define four interiorly-extending longitudinal projections defined therebetween four exteriorly-projecting lobes;  wherein said predetermined number is greater than four lattice positions and less than nine lattice positions; and  wherein said area of said cross-sectional region, said predetermined number, and said pitch define a water rod efficiency greater than about 0.7; and,  at least one projection on an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said sidewall, at least in a portion substantially adjacent to said projection, to permit passage of said projection over an obstruction when said water rod is axially moved proximate to said obstruction.  a hollow longitudinally-extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy a predetermined number of lattice positions of the bundle;  said cross-sectional interior region being configured to define a substantially rectangular shape;  wherein said predetermined number is greater than four lattice positions and less than nine lattice positions; and  wherein said area of said cross-sectional region, said predetermined number, and said pitch define a water rod efficiency greater than about 0.7.  at least one projection attached to an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said sidewall, at least in a portion substantially adjacent to said projection, to permit passage of said projection over an obstruction when said water rod is axially moved proximate to said obstruction.  a hollow, longitudinally extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy a predetermined number of lattice positions of the bundles;  said cross-sectional interior region being configured to define two substantially circular portions, said circular portions being substantially adjacent;  wherein said predetermined number is greater than four lattice positions and less than nine lattice positions; and  wherein said area of said cross-sectional region, said predetermined number, and said pitch define a water rod efficiency grater than about 0.6.  at least one projection on an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said at least in a portion substantially adjacent to said projection, to permit passage of said projection over said first means when said water rod is axially moved proximate to said first means.  first means for spatially positioning rods wherein said means defines a lattice having a plurality of lattice positions and a lattice pitch;  a plurality of nuclear fuel rods operably connected with said means for positioning, wherein said nuclear fuel rods occupy at least some of said lattice positions;  at least one hollow longitudinally extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy greater than four and fewer than nine lattice positions of said lattice;  said cross-sectional interior region being configured to define two round-cornered triangular regions continuously connected by a constricted region, said constricted region being defined by two inwardly extending longitudinal projections;  wherein the area of said cross-sectional region for said tubes, said number of occupied positions for said tubes, and said pitch define a water rod efficiency greater than about 0.7; and,  at least one projection on an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said sidewall, at least in a portion substantially adjacent to said projection, to permit passage of said projection over an obstruction when said water rod is axially moved proximate to said obstruction.  first means for spatially positioned rods wherein said means defines a lattice having a plurality of lattice positions and a lattice pitch;  a plurality of nuclear fuel rods operably connected with said means for positioning, wherein said nuclear fuel rods occupy at least some of said lattice positions;  at least one hollow longitudinally extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy greater than four and fewer than nine lattice positions of said lattice; and  said cross-sectional interior region being configured as a rectangle; and  wherein the area of said cross-sectional region of said tubes, said number of occupied positions of said tubes, and said pitch define a water rod efficiency greater than about 0.7.  at least one projection attached to an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said sidewall, at least in the portion substantially adjacent to said projection, to permit passage of said projection over said first means when said water rod is axially moved proximate to said first means.  first means for spatially positioning rods wherein said means defines a lattice having a plurality of lattice positions and a lattice pitch;  a plurality of nuclear fuel rods operably connected with said means for positioning, wherein said nuclear fuel rods occupy at least some of said lattice positions;  at least one hollow longitudinally extending tube having a sidewall which defines a cross-sectional interior region of said tube, configured to substantially occupy greater than four and fewer than nine lattice positions of said lattice;  said cross-sectional interior region being configured to define two substantially circular regions being substantially adjacent; and  wherein the area of said cross-sectional region of said tubes, said number of occupied positions of said tubes, and said pitch define a water rod efficiency greater than about 0.6.  at least one projection on an exterior portion of said sidewall; and  wherein said sidewall has sufficient resiliency to permit inward flexing of said sidewall, at least in a portion substantially adjacent to said projection, to permit passage of said projection over said first means when said water rod is axially moved proximate to said first means. 2. A water rod, as claimed in claim 1, wherein said predetermined number is seven. 3. A water rod, usable for containing water in a substantially interior position in a nuclear fuel rod bundle, the bundle having a plurality of lattice positions spaced at a predetermined lattice pitch, comprising: 4. A water rod, as claimed in claim 2, wherein said predetermined number is five. 5. A water rod, usable for containing water in a substantially interior position in a nuclear fuel rod bundle, the bundle having a plurality of lattice positions spaced at a predetermined lattice pitch, comprising: 6. A water rod, as claimed in claim 5, wherein said predetermined number is seven. 7. A water rod, as claimed in claim 5, further comprising: 8. A water rod, usable for containing water in a substantially interior position in a nuclear fuel rod bundle, the bundle having a plurality of lattice positions spaced at a predetermined lattice pitch, comprising: 9. A water rod, as claimed in claim 8, herein said predetermined number is seven. 10. A water rod, as claimed in claim 8, further comprising: 11. A nuclear fuel rod bundle comprising: 12. A nuclear fuel rod bundle, as claimed in claim 11, wherein the number of said lattice positions occupied by said tubes is seven. 13. A nuclear fuel rod bundle comprising: 14. A nuclear fuel rod bundle, as claimed in claim 13, wherein the number of lattice positions occupied by said tubes is 7. 15. A nuclear fuel rod bundle, as claimed in claim 13, further comprising: 16. A nuclear fuel rod bundle comprising: 17. A nuclear fuel rod bundle, as claimed in claim 16, wherein the number of said lattice positions occupied by said tubes is seven. 18. A nuclear fuel rod bundle, as claimed in claim 16, further comprising: