Manufacture of nuclear reactor fuel elements

Claim 1

APPARATUS FOR INWARDLY DEFORMING A CIRCUMFERENTIAL BAND OF A TUBULAR NUCLEAR REACTOR FUEL ELEMENT SHEATH INTO ENGAGEMENT WITH A CIRCUMFERENTIAL GROOVE AROUND A CYLINDRICAL MEMBER CONTAINED WITHIN THE FUEL ELEMENT SHEATH, COMPRISING: A PRESSURE RESISTANT HOUSING HAVING A PASSAGEWAY THERETHROUGH TO RECEIVE AND PROPORTIONED TO FIT SNUGLY ABOUT A FUEL ELEMENT SHEATH; AND ANNULAR POCKET AROUND AND OPENING INWARDLY AT AN ANNULAR MOUTH TO SAID PASSAGEWAY, THE WALLS OF THE ANNULAR POCKET IN CROSS SECTION TAPERING OUTWARDLY FROM THE ANNULAR MOUTH OF THE POCKET; MEANS FOR EXERTING AN INWARDLY ACTION DEFORMING PRESSURE ON THE REGION OF THE FUEL ELEMENT SHEATH SURROUNDED BY THE MOUTH OF THE ANNULAR POCKET WHEN THE FUEL ELEMENT SHEATH IS INSERTED IN THE PASSAGEWAY IN THE HOUSING COMPRISING AN ELASTICALLY COMPRESSIBLE ANNULAR RING IN SAID ANNULAR POCKET, AT LEAST A PORTION OF THE CROSSSECTIONAL AREA OF SAID ELASTICALLY COMPRESSIBLE RING BEING OF GREATER LONGITUDINAL DIMENSIONS THAN THE LONGITUDINAL WIDTH OF SAID ANNULAR MOUTH, MEANS FOR PRESSURIZING HYDRAULIC FLUID IN SAID ANNULAR POCKET TO ACT ON THE OUTER PERIPHERY OF THE ELASTICALLY COMPRESSIBLE ANNULAR RING AND COMPRESS THE RING RADIALLY INWARDS ONTO THE FUEL ELEMENT SHEATH IN THE REGION TO BE DEFORMED, THE ANNULAR RING SEALING ON THE WALLS OF THE POCKET WHICH TAPER OUTWARDLY FROM THE ANNULAR MOUTH OF THE POCKET, THE CONTACT PRESSURE BETWEEN THE RING AND SAID WALLS INCREASING WITH INCREASE OF PRESSURE IN THE HYDRAULIC FLUID TO FORM A PRESSURE TIGHT FLUID SEAL. SURE TIGHT FLUID SEAL.