Patent US3683148A successfully refreshed from Google Patents.
US3683148A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of nuclear fuel assemblies and resultant product
Assignee: Individual
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Filing: 1970-05-05
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Granted: 1972-08-08
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Expires: 1990-05-05
Abstract
Abstract A nuclear fuel assembly has an end plug and is sealed except for a small diameter axial bore in the plug. The plug provides a collar around the outer end of the bore which when fused provides sufficient material to seal the bore. Before the bore is sealed the assembly is filled with an inert-gas at high pressure. An electric arc is then established between an electrode and the collar to melt the collar sufficiently to seal the bore.
Inventors
- 👤 Eugene S Boyko
- 👤 Joseph Campbell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:50
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/02; G21C3/04; G21C3/06; G21C3/10; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
186 words
The method of constructing a pressurized nuclear fuel unit the steps comprising, (a) assembling a predetermined quantity of nuclear fuel in an enclosure which enclosure is formed from a thin-walled elongated tube having an end plug welded to one end of the tube and another end plug welded to the opposite end of the tube, at least one of said end plugs having an opening extending from the interior to the exterior of the enclosure (b) placing at least a portion of the plug containing the opening within a sealed chamber (c) evacuating the sealed chamber and the interior of the enclosure (d) backfilling said sealed chamber with an inert gas to provide a predetermined pressure of said gas within the chamber and the interior of the enclosure (e) supplying a source of heat within the chamber adjacent the opening in the end plug for fusing the end plug adjacent the opening to establish a seal for said opening (f) removing the source of heat, (g) cooling the portion of the enclosure in the chamber (h) and thereafter removing the pressurized sealed unit from the chamber.
Claim 2
Independent Claim
186 words
The method of constructing a pressurized nuclear fuel unit the steps comprising, (a) assembling a predetermined quantity of nuclear fuel in an enclosure which enclosure is formed from a thin-walled elongated tube having an end plug welded to one end of the tube and another end plug welded to the opposite end of the tube, at least one of said end plugs having an opening extending from the interior to the exterior of the enclosure (b) placing at least a portion of the plug containing the opening within a sealed chamber (c) evacuating the sealed chamber and the interior of the enclosure (d) backfilling said sealed chamber with an inert gas to provide a predetermined pressure of said gas within the chamber and the interior of the enclosure (e) supplying a source of heat within the chamber adjacent the opening in the end plug for fusing the end plug adjacent the opening to establish a seal for said opening (f) removing the source of heat, (g) cooling the portion of the enclosure in the chamber (h) and thereafter removing the pressurized sealed unit from the chamber.
Claim 3
Dependent Claim
45 words
The method as claimed in claim 1 wherein said plug is an electroconductive fusible plug and said heating comprises striking a fixed electric arc with said plug as one electrode for the arc and fusing material with said fixed electric arc to fill said opening.
Claim 4
Dependent Claim
79 words
The method as claimed in claim 2 wherein said gas is selected from the group consisting of helium and argon, said enclosure being constructed by sealing a plug to one end of a tubular member having its other end closed, the plug having said opening formed as an axial opening therein, said gas being at a pressure substantially greater than atmospheric pressure, said enclosure being constructed of material selected from the group consisting of stainless steel and zirconium alloy.
Claim 5
Independent Claim
167 words
The method of constructing a pressurized nuclear fuel unit the steps of comprising, (a) inserting nuclear fuel into a thin-wall elongated metal tube, (b) welding a separate metal plug to each end of the metal tube to form a container for the nuclear fuel, one of said plugs having an axial opening constituting the only communication path between the interior and exterior of the container, (c) inserting at least the metal plug having the axial opening in a sealed chamber, (d) evacuating the chamber and the interior of the container (e) backfilling the chamber and the interior of the container with an inert gas to establish a predetermined pressure of said gas therein, (f) fusing metal within said opening to hermetically seal said container, said fusing including the generation of an electric arc within said opening to establish metal fusing heat at the opening (g) terminating the generation of the electric arc, and cooling the contents of the chamber while under the influence of the inert gas.
Claim 6
Independent Claim
167 words
The method of constructing a pressurized nuclear fuel unit the steps of comprising, (a) inserting nuclear fuel into a thin-wall elongated metal tube, (b) welding a separate metal plug to each end of the metal tube to form a container for the nuclear fuel, one of said plugs having an axial opening constituting the only communication path between the interior and exterior of the container, (c) inserting at least the metal plug having the axial opening in a sealed chamber, (d) evacuating the chamber and the interior of the container (e) backfilling the chamber and the interior of the container with an inert gas to establish a predetermined pressure of said gas therein, (f) fusing metal within said opening to hermetically seal said container, said fusing including the generation of an electric arc within said opening to establish metal fusing heat at the opening (g) terminating the generation of the electric arc, and cooling the contents of the chamber while under the influence of the inert gas.
Claim 7
Dependent Claim
54 words
The method as claimed in claim 4 wherein said inert gas is introduced into the container at a selected pressure in excess of atmospheric pressure, said selected pressure being such that the internal pressure of the container does not exceed 2,200 pounds per square inch throughout the useful life of the nuclear fuel assembly.
Claim 8
Dependent Claim
28 words
The method as claimed in claim 5 wherein said tube and said plugs are constructed of material selected from the group consisting of stainless steel and zirconium alloy.
Claim 9
Dependent Claim
34 words
The method as claimed in claim 5 wherein the plug having an axial opening has a collar around the opening, said fusing comprising the melting of metal in said collar to fill the opening.
Claim 10
Dependent Claim
50 words
In the method as claimed in claim 5 wherein said electric arc is established by extending a welding electrode through a wall of the chamber, the step of forming a collar on the porTion of the electrode located within the chamber to prevent ejection of the electrode from the chamber.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |