Shielded Neutron Shipping Cask.

Abstract

A shielded neutron shipping cask was designed to transport three gram quantities of californium 252. The cask weighs 25 tons and may be shipped by common carrier anywhere in the United States. Neutron sources will be packaged In all-metal pressure vessels suitable for use at 1500 F. Three source vessels* each three inches in diameter by twelve inches long, may be stored in a rotating magazine at the center of the cask. An eight-foot-long plug with grapple fingers locks the magazine during transport and is also used to remotely load or unload the neutron-source vessels. A Boral plate is used to absorb slow neutrons and a steel billet provides primary-gamma shielding near the center of the cask. The neutron shield consists of borated llmonite concrete and borated gypsum cast into the cavities formed by two concentric steel shells. An additional center core has 252 been designed to transport three 4-inch-dlameter by 5-feet-long Cf bearing irradiated fuel tubes in this carrier.

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