Patent Number: 040615367
Section: claims

1. A fuel assembly for a nuclear reactor comprising: a plurality of fuel elements disposed in a parallel array;  multiple hollow control rod guide tubes positioned in a predetermined pattern among said fuel elements;  a plurality of grids of egg-crate configuration having openings therein through which said fuel elements and guide tubes extend for imparting lateral support thereto;  said plurality of grids including top and bottom grids respectively located adjacent the top and bottom of said assembly, and at least one grid intermediate said top and bottom grids;  said grids except said top and bottom grids including coolant mixing vanes thereon which impart a mixing action to coolant adapted to flow upwardly through the assembly;  means securing each of said guide tubes to said grids;  flow apertured plate means adjacent opposite ends of said fuel elements and guide tubes, said plate means at one end supporting said fuel elements and guide tubes and at the other end supporting said guide tubes;  a common header holding multiple control rods designed for telescopic and longitudinal movement in the corresponding guide tubes.  said means securing each of said guide tubes to said grid comprises a weld made between each tab and its corresponding guide tube to provide a skeletal structure which permits longitudinal expansion and contraction of said fuel elements during reactor operation. 2. The fuel assembly according to claim 1 wherein each of said grids includes multiple tabs shaped to the configuration of said guide tubes; and wherein