Rupture Testing of UF6 Transport and Storage Cylinders

Large steel cylinders for shipment and storage of uranium hexafluoride have been in production since about 1951, in support of the United States Department of Energy (DOE) programs for nuclear fuel enrichment services. These 48-inch diameter cylinders, in 10- and 14-ton capacities and intended for use with feed, tails, and low-enrichment U-235 intermediate product, have been purchased in several minor design variations and comprise about 46,500 cylinders at the present time. In addition, DOE's uranium enrichment operations own a large number of smaller product cylinders: more than 3,000 type 30A steel cylinders, about 1,650 5-, 8-, and 12-inch product cylinders made of nickel and Monel, and about 2,000 small sample cylinders of nickel and Monel. The total number of UF6 containers in world-wide distnbution is unknown but must number well in excess of 100,000 units. Handling accidents, such as the damaged cylinders from the Monte Louis, the Portsmouth, and Kerr-McGee incidents, and many other handling and transport accidents of lesser consequence, along with governmental policies and industrial practices which have a bearing on long-term storage of feed or processed materials all raise proper concerns about the ability of these cylinders to safely contain uranium hexafluoride.