Qualification of the DAHER-NCS Fuel Rod Encapsulation Process for Transport and Storage

During the previous PATRAM in 2010, DAHER-NCS has presented a new concept for the encapsulation of spent fuel rods. This process is required in order to allow the transport of damaged rods. For these last three years, DAHER-NCS has kept continuing the improvement and qualification of the encapsulation device. For the qualification process a smaller test model was used. In the meantime a full size prototype of the brazing equipment was designed and manufactured. This prototype was successfully tested in dry conditions as well as submerged under water in a spent fuel pool. The quality of the drying process and the brazed plugs is reproducible in all tested conditions and comparable to the results of the brazing of the device used for the qualification process. Furthermore a test method to check and guarantee the leak tightness of the encapsulated rods was developed and validated. The leak tightness is proven by an integral Helium leakage test. Within the next two years the operation in three European nuclear power plants (BWR and PWR) is projected. Currently the transport within the type B(U)F package NCS45 of brazed capsules produced by this process is licensed. So DAHER-NCS provides a solution for the removal of damaged spent fuel rods out of the pool and their transport in safe conditions. The next step will be to qualify the brazed capsules for long term intermediate storage.