Abstract: A low cost, minimum weight cask for the storage of fuel assemblies is disclosed herein, along with a method for the construction thereof. The cask generally comprises a wall assembly for defining a cask interior that is complementary in shape to a rectangular array of radioactive fuel assemblies that is formed from four flat, metallic wall plate members having mutually parallel side edges which are adjoined be welds that penetrate only part way through the thicknesses of the wall plate members. The cask further includes a floor plate attached to the bottom of the wall assembly, and a lid that is detachably connectable to the top of the wall assembly. A basket assembly formed from parallel and uniformly spaced plates of borated aluminum interconnected in "egg crate" fashion is disposed in the rectangular interior of the cask. To minimize weight, each of the corners of the wall assembly is truncated.

Abstract: A shipping cask for transporting radioactive material is disclosed herein which comprises an inner vessel having metallic, heat conducting walls, a plurality of heat conductive, mutually parallel ribs, wherein the inside edge of each is connected to the outside surface of the heat conducting wall of the inner vessel, a layer of neutron absorbing cement disposed over the exterior of the inner vessel and between the mutually parallel ribs, and a plurality of flat circumferentially disposed fin members, each of which has two opposing and mutually parallel edges that are welded to the outer edges of two adjacent ribs. The flat circumferentially disposed fin members dissipate heat conducted through the ribs generated by radioactive material within the inner vessel, and further serve both to support and protect the brittle layer of cement, as well as to provide a watertight barrier thereover so that the cask may be submerged or otherwise exposed to water without absorbing any significant amounts.

Abstract: A closure system of a spent fuel storage cask includes a lid assembly having a shield lid which is installed under water and which cooperates in the drainage of water from the cask. A primary cover having a spring energized metalic C-ring captured therein to provide a primary gas seal is then installed over the shield lid. Closable gas passages extending through the primary cover permit the primary gas seal to be tested by injecting pressurized gas on one side of the primary gas seal and testing for leakage on the other. A seal cover is installed over the primary cover and welded at its periphery to provide the secondary gas seal. The seal cover has a closable gas passage which allows pressurized gas to be injected between the primary cover and the sealed cover so that leaks at the secondary gas seal can be detected. The closure system may also include a gas pressure monitoring system which communicates with the interior of the cask and which can be recalibrated during long-term storage of spent fuel.

Abstract: A shipping cask for transporting radioactive material is disclosed herein which comprises an inner vessel having metallic, heat conducting walls, a plurality of heat conductive, mutually parallel ribs, wherein the inside edge of each is connected to the outside surface of the heat conducting wall of the inner vessel, a layer of neutron absorbing cement disposed over the exterior of the inner vessel and between the mutually parallel ribs, and a plurality of flat circumferentially disposed fin members, each of which has two opposing and mutually parallel edges that are welded to the outer edges of two adjacent ribs. The flat circumferentially disposed fin members dissipate heat conducted through the ribs generated by radioactive material within the inner vessel, and further serve both to support and protect the brittle layer of cement, as well as to provide a watertight barrier thereover so that the cask may be submerged or otherwise exposed to water without absorbing any significant amounts.

Abstract: An improved shipping cask for transporting fuel rods is disclosed herein. The cask comprises a cylindrical vessel, and a basket structure disposed in the interior thereof for holding a plurality of spent fuel containers. A plurality of plate-like former members circumscribe the basket structure, and include shock-absorbing portions formed from a network of ligaments which deformably yield when mechanical shock of a selected magnitude is applied onto the side of the cylindrical vessel that contains the basket structure. Additionally, the former members are formed from a metal having a greater thermal coefficient of expansion than the wall of the cylindrical vessel, and are dimensioned so that the basket structure is freely receivable within the interior of the cylindrical vessel at ambient temperature, but becomes frictionally bound within this interior as a result of greater relative thermal expansion whenever heat-radiating fueld rods are loaded into the fuel rod containers of the basket structure.

Abstract: A cask for storing spent nuclear fuel after removal from a pool of water includes a container with a cylindrical cavity and a basket which is inserted into the container. The basket includes disk-like grid assemblies which provide spent fuel storage slots and which are coaxially mounted at spaced-apart positions, each grid assembly having a diameter that is slightly less than the one above it. If fuel assemblies are to be stored, hollow cells are affixed to one of the grid assemblies and positioned in the others by heat-conducting wedges which permit the basket and cells to expand at different rates. Rings which project slightly into the interior of the container are provided on the container walls, each ring being positioned to be in alignment with the periphery of a corresponding grid assembly after the basket is inserted into the container.

Abstract: A cooling fin for a spent nuclear fuel storage cask is fabricated by bending an elongated composite sheet, formed by cladding a stainless steel sheet onto a carbon steel sheet, along its axis to provide two sides joined at a curved apex. The free ends of the sides are welded to the base element of the cask. A pocket is formed between the sides of the fin by welding an end plate to the bottom of the fin, and thereafter resinous neutron absorbing material is poured into the pocket. After the pocket is filled an end plate is welded to the top of the fin.