Containment and Analysis Capability Insights Gained from Drop TestingRepresentative Spent Nuclear Fuel Containers

摘要

The National Spent Nuclear Fuel Program (NSNFP), operating from the Idaho National Engineering andEnvironmental Laboratory (INEEL), developed the standardized Department of Energy (DOE) spent nuclear fuel (SNF)canister. This canister is designed to be loaded with DOE SNF (including other radioactive materials) and then be usedduring interim storage, during transportation to the nation's repository, and for final disposal at the repository withouthaving to be reopened. The canister has been fully designed and has completed significant testing that clearly demonstratesthat it can safely achieve its intended design goals.During 1999, nine 457-mm diameter test canisters were fabricated at the INEEL to represent the standardized DOESNF canister design. Various 'worst case' internals were incorporated. Seven of the test canisters were 4.57 m long andweighed approximately 2721 kg, while two were 3.00 m long and weighed approximately 1360 kg and 1725 kg. Seven ofthe test canisters were dropped from 9 m onto an essentially unyielding flat surface and one of the test canisters was droppedfrom 1 m onto a 15-cm diameter puncture post. The final test canister was dropped from 61 cm onto a 50.8 mm thickvertically oriented steel plate, and then fell over to impact another 50.8 mm thick vertically oriented steel plate. This last testrepresented a canister dropping onto another larger container such as a repository disposal container or waste package. The1999 drop testing was performed at Sandia National Laboratories (SNL). The nine test canisters experienced varyingdegrees of damage to their skirts, lifting rings, and pressure boundary components (heads and main body). However, all ofthe canisters were shown to have maintained their pressure boundary (through pressure testing). Four heavily damagedcanisters were also shown to be leaktight via helium leak testing. Pre- and post-drop finite element (FE) analyses were alsoperformed. The results clearly indicated that accurate predictions of canister responses to the drop tests were achieved.The results achieved for the standardized canister can also be applicable to other well-constructed containers(canisters, casks, cans, vessels, etc.) subjected to similar loads. Properly designed containers can maintain a containmentsystem after being subjected to dynamically induced high strains and FE computer analyses can accurately predict theresulting responses.