PERFECCIONAMIENTOS EN CONJUNTOS DE ELEMENTOS COMBUSTIBLES PARA REACTORES NUCLEARES.

摘要

1338462 Fuel elements UNITED KINGDOM ATOMIC ENERGY AUTHORITY 20 June 1972 [7 July 1971] 32004/71 Heading G6C A spacer grid for a fuel pin assembly comprises a rigid grid structure 2 of intersecting cross members 3 defining cells each of which is penetrated by a fuel pin (not shown) and resilient strip members 5 slotted through the grid structure 2 parallel to the cross members 3. The resilient strip members 5 are provided at four levels and extend on either side of the cross members 3 in order to provide transverse support for the fuel pins. The freedom of lateral vibration of the fuel pins is limited by dimple-shaped stops 7 formed projecting from the faces of the cross members 3 in the cells of the grid structure 2. Each of the stops 7 underlies one of the strip members 5 and a small clearance exists between each stop 7 and the back face of the corresponding strip member 5. Any fretting in the fuel pin assembly is taken at the points of tapping of the back faces of the strip members 5 with the stops 7 and hence fretting between the fuel pins and the strip members 5 at their points of contact is minimized.