| 摘要 |
967, 162. Fuel elements. COMMISSARIAT A L'ENERGIE ATOMIQUE. Aug. 8, 1963 [Aug. 16, 1962], No. 31333/63. Heading G6C. A nuclear fuel element for gas cooled reactors comprises a cluster of fuel rods held in a fixed lattice by structural members including two end grids, fuel spaces within the fuel rods being interconnected via small channels in one of the end grids to which the fuel rods are attached, the interconnected spaces being further connected with free spaces formed in rigid structural members connecting the grids. The spaces act as reservoirs for fission product gases, and the fuel rods, preferably canned uranium dioxide rings, are preferably free to slide in the other grid to allow for relative expansion. The fuel rods 2 have brazed welded or soldered end plugs 3, 4, the channelled end plugs 3 being brazed to the channelled grid 7. The axially free ends of the fuel rods have extensions 11 which slide in the other end grid 10. The two grids are held together by a series of hollow tie rods 16, the spaces therein being connected to channels 14 in the end grid 7. After brazing the fuel rod plugs to the end grid 7, the assembly is completed by closing joint access holes in the grid with plugs 13. In a modification, (Fig. 3, not shown) the grid to which the fuel rod plugs are brazed is made in two disc like halves which are jointed after brazing the fuel rod plugs. The additional gas space provided by the hollow tie rods may be supplemented or replaced by space provided in a central non fissile rod and/or an outer jacket. The central rod mentioned may act as the only tie between the two grids. |
