Patent Number: 042740070
Section: claims

1. A radiation shielding transport and storage vessel comprising: a cast metal upright receptacle having a wall surrounding a space adapted to receive radioactive material and a bottom unitary with said wall, said space opening at the top of said vessel in a recess;  a plug-type radiation-shielding cover received in said recess and complementarily fitting said space, whereby said recess and said cover have complementary and confronting surfaces;  a plurality of annular seals disposed between and bridging said surfaces so as to define at least one control compartment between;  means forming at least one passage accessible from outside the vessel and communicating with said control compartment for monitoring a control gas in said vessel; and  a safety cover overlying said plug cover and peripherally overhanging same while being recessed in said receptacle. 2. The vessel defined in claim 1 wherein a seal is provided between a rim of said safety cover and said receptacle outwardly of said plug-type cover and defines a further control compartment with a seal between said surfaces, said further control compartment being connected to a gas passage. 3. The vessel defined in claim 2 wherein said surfaces are frustoconical and downwardly tapered. 4. The vessel defined in claim 3 wherein a plurality of O-rings are provided along said surfaces in axial spaced relation to form respective seals defining respective compartments between them. 5. The vessel defined in claim 4 wherein said plug-type cover is provided with an end portion juxtaposed with a shield of said wall at the bottom of said recess, a respective O-ring being provided between said shoulder and said end portion. 6. The vessel defined in claim 5 wherein said plug-type cover is provided with an outwardly extending flange, juxtaposed with a ledge of said wall at the top of said recess, said ledge and said flange having an O-ring interposed between them. 7. The vessel defined in claim 5 or claim 6, wherein each of said O-rings is received in a respective groove formed in said plug-type cover.