| 摘要 |
1372100 Fuel elements SIEMENS AG 10 Dec 1971 [11 Dec 1970] 57608/71 Heading G6C A fuel rod casing comprises a tube 2 containing nuclear fuel and a shorter tube 1 through which the tube 2 extends, spacing means 3 extending between the tubes 1, 2 and coolant flowing through the resultant annular space between the tubes 1, 2. The support means 3, which may be longitudinal ribs (as shown) or helical ribs (to achieve a turbulence effect in the coolant) are welded to the tubes 1, 2. With long fuel rods, there are a number of tubes 1 distributed axially along the rods. On assembling a plurality of these fuel rods into a fuel element, the tubes 1 bear against each other and, depending on the further design of the fuel element, it may be necessary to wind about the bundle of rods at each spacer level a binding, if such is not already provided by the presence of outer structural elements such as the fuel element casing. |
