Investigation of Breached Depleted UF₆ Cylinders

Conference · Tue Oct 29 00:00:00 EST 1991

OSTI ID:139656

DeVan, J. H. ^[1]

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1. Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF₆, two 14-ton cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. An investigation team was immediately formed to determine the cause of the failures and their impact on future storage procedures and to recommend corrective actions. Subsequent investigation showed that the failures most probably resulted from mechanical damage that occurred at the time that the cylinders had been placed in the storage yard. In both cylinders evidence pointed to the impact of a lifting lug of an adjacent cylinder near the front stiffening ring, where deflection of the cylinder could occur only by tearing the cylinder. The impacts appear to have punctured the cylinders and thereby set up corrosion processes that greatly extended the openings in the wall and obliterated the original crack. Fortunately, the reaction products formed by this process were relatively protective and prevented any large-scale loss of uranium. The main factors that precipitated the failures were inadequate spacing between cylinders and deviations in the orientations of lifting lugs from their intended horizontal position. After reviewing the causes and effects of the failures, the team's principal recommendation for remedial action concerned improved cylinder handling and inspection procedures. Design modifications and supplementary mechanical tests were also recommended to improve the cylinder containment integrity during the stacking operation.

• Research Organization: Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: AC05-76OR00001
• OSTI ID: 139656
• Report Number(s): CONF-9110117; ON: DE92005283; TRN: 94:007283
• Resource Relation: Conference: 2. International Conference on Uranium Hexafluoride Handling, Lessons Learned, Oak Ridge, TN (United States), 29-31 Oct 1991; Other Information: PBD: [1991]; Related Information: Is Part Of Uranium hexafluoride handling; Proceedings; PB: 295 p.
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
96 KNOWLEDGE MANAGEMENT AND PRESERVATION
URANIUM HEXAFLUORIDE
PRESSURE VESSELS
DAMAGE
INVESTIGATIONS
INSPECTION
FAILURES
CORROSION
SAFETY
Nuclear Criticality Safety Program (NCSP)
Concrete Saddles
Uranium Hexafluoride
Gravel Storage Pads
Diffusion Plants
Failure Analysis
Radioactive Decay
Green Salt Deposits