Fuel or irradiation subassembly

Claim 2

A SUBASSEMBLY FOR USE IN A NUCLEAR REACTOR COMPRISING A BUNDLE OF PARALLEL PINS INCORPORATING NUCLEAR FUEL OR A MATERIAL TO BE IRRRADIATED ENCLOSED WITHIN A COOLANT TUBE HAVING AN ANNULAR UNDERCUT PORTION IN THE LOWER PORTION OF THE COOLANT TUBE, AN INNER TUBE WITHIN SAID COOLANT TUBE AND SURROUNDING SAID BUNDLE OF PINS, A COOLANT TUBE SURROUNDING SAID INNER TUBE, AND A LOCKING COMB CONSISTING OF A HEAD AND A PLURALITY

Claim 3

A subassembly according to claim 1 and including a coupling member having a central bore and a support grid for the pins extending thereacross, said inner tube overlapping a reduced portion of said coupling member, the coupling member having slots therein aligned with the slots in the inner tube whereby the locking comb locks the inner tube, the coupling member and the pins into a fixed position.

Claim 4

A subassembly according to claim 2 wherein the pins are irradiation capsules and the irradiation capsules are disposed in triangular array in a hexagonal bundle and the coolant tube and inner tube are hexagonal in cross section.

Claim 5

An irradiation subassembly according to claim 3 wherein said locking comb includes an even number of teeth, the two central teeth being disposed on opposite sides of a central row of irradiation capsules engaging the undercut portions therein and in the irradiation capsules in the adjacent rows and additional pairs of teeth are disposed between alternate rows of pins whereby every pin is engaged by at least one locking comb tooth.

Claim 6

An irradiation assembly according to claim 4 and including locating pockets in the grid for the tips of the pins.

Claim 7

A subassembly according to claim 3 wherein said locking comb includes an even number of teeth disposed between all rows of irradiation capsules engaging the undercut portions thereof.

Claim 8

A subassembly according to claim 6 wherein the teeth are relieved at noncontact points to increase the available flow area.

Claim 9

An irradiation subassembly comprising a hexagonal bundle of elongated, parallel irradiation capsules disposed in triangular array within a hexagonal inner tube which in turn is disposed within a hexagaonal coolant tube, said coolant tube having an annular undercut portiOn in the lower portion thereof, a top end fixture at one end of the coolant tube and a lower adapter at the other end thereof, radiation shields in said coolant tube above and below said bundle of pins, a coupling member joining the inner hex tube to the lower radiation shield and overlapping the inner hex tube, said coupling member having a central bore with a support grid for the irradiation capsules extending thereacross, the inner hex tube having slots therein on opposite sides thereof and the coupling member having cutaway portions therein on opposite sides thereof, said slots and cut-away portions being aligned, and a locking comb consisting of a flat, angular head and an even number of teeth extending outwardly therefrom in a direction parallel to a line bisecting the angle, said locking comb being disposed in the irradiation assembly so that the head engages one of the openings in the inner hex tube and coupling member, the tips of the teeth engage the other openings and the teeth engage the undercut portion on at least one side of each irradiation capsule, the head being adapted to fit within one of the angles of the hexagonal coolant tube.

Claim 10

An irradiation subassembly comprising a hexagonal bundle of elongated, parallel irradiation capsules disposed in triangular array within a hexagonal inner tube which in turn is disposed within a hexagaonal coolant tube, said coolant tube having an annular undercut portiOn in the lower portion thereof, a top end fixture at one end of the coolant tube and a lower adapter at the other end thereof, radiation shields in said coolant tube above and below said bundle of pins, a coupling member joining the inner hex tube to the lower radiation shield and overlapping the inner hex tube, said coupling member having a central bore with a support grid for the irradiation capsules extending thereacross, the inner hex tube having slots therein on opposite sides thereof and the coupling member having cutaway portions therein on opposite sides thereof, said slots and cut-away portions being aligned, and a locking comb consisting of a flat, angular head and an even number of teeth extending outwardly therefrom in a direction parallel to a line bisecting the angle, said locking comb being disposed in the irradiation assembly so that the head engages one of the openings in the inner hex tube and coupling member, the tips of the teeth engage the other openings and the teeth engage the undercut portion on at least one side of each irradiation capsule, the head being adapted to fit within one of the angles of the hexagonal coolant tube.

Claim 11

An irradiation assembly according to claim 8 wherein there are 37 irradiation capsules and four teeth on the locking comb, the innermost teeth engaging the undercut portions of the central row of irradiation capsules on both sides thereof and the outermost teeth being disposed between the two outermost rows of irradiation capsules and including locating pockets in the grid for the tips of the irradiation capsules.

Claim 12

An irradiation assembly according to claim 8 wherein there are 37 irradiation capsules and the locking comb has six teeth disposed between all rows of irradiation capsules, said teeth being relieved at noncontact points.