US3801453A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel assembly for power generating nuclear reactor
Assignee: UNC NUCLEAR INDUSTRIES Inc A CORP OF
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Filing: 1972-02-11
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Granted: 1974-04-02
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Expires: 1992-02-11
Abstract
Abstract A fuel assembly especially adapted for a pressurized water reactor is described. It comprises a support assembly of control element guide tubes, upper and lower end fittings, and grid spacers holding a plurality of fuel rods in vertical parallel relation. The fuel assembly features a removable upper end fitting allowing on-site access to and removal of individual fuel rods, and a novel guide tube construction providing high volume coolant flow through the assembly and allowing ready access of a grapple having laterally, outwardly extending gripping fingers to the assembly for lifting purposes.
Inventors
- 👤 C Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:05
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C3/334; G21C3/33; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
113 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving hollow, empty guide tubes and supporting in spaced parallel relation a plurality of separable upright fuel rods, fastening means removable from the top and removably connecting said upper end fitting directly to the guide tubes and separable from the guide tubes enabling individual fuel rod removal from the assembly, and means connected to the fastening means for lifting the assembly whereby the load path extends through said guide tubes, said fastening means being hollow to enable control rod passage therethrough.
Claim 2
Dependent Claim
113 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving hollow, empty guide tubes and supporting in spaced parallel relation a plurality of separable upright fuel rods, fastening means removable from the top and removably connecting said upper end fitting directly to the guide tubes and separable from the guide tubes enabling individual fuel rod removal from the assembly, and means connected to the fastening means for lifting the assembly whereby the load path extends through said guide tubes, said fastening means being hollow to enable control rod passage therethrough.
Claim 3
Dependent Claim
40 words
A fuel assembly as claimed in claim 1 characterized in that the lower end fitting comprises an apertured plate permanently secured to the guide tube lower ends, and the fuel rods rest on the surface of the lower end fitting.
Claim 4
Dependent Claim
29 words
A fuel assembly as claimed in claim 2 characterized in that a plurality of said fuel rods are each aDjacent a plurality of apertures in the lower end fitting.
Claim 5
Dependent Claim
127 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving guide tubes and supporting in spaced parallel relation a plurality of upright fuel rods, said upper end fitting being removably connected to the guide tubes and separable from the guide tubes and fuel rods enabling individual fuel rod removal from the assembly, said upper end fitting comprising separable top and bottom parts, said bottom part having an array of first apertures for receiving the upper ends of the guide tubes and an array of large second apertures for coolant flow, and removable fastening means for securing the said bottom part to the guide tubes.
Claim 6
Dependent Claim
127 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving guide tubes and supporting in spaced parallel relation a plurality of upright fuel rods, said upper end fitting being removably connected to the guide tubes and separable from the guide tubes and fuel rods enabling individual fuel rod removal from the assembly, said upper end fitting comprising separable top and bottom parts, said bottom part having an array of first apertures for receiving the upper ends of the guide tubes and an array of large second apertures for coolant flow, and removable fastening means for securing the said bottom part to the guide tubes.
Claim 7
Dependent Claim
30 words
A fuel assembly as claimed in claim 4 characterized in that the fastening means comprise nuts secured to threaded ends of only some but not all of the guide tubes.
Claim 8
Dependent Claim
29 words
A fuel assembly as claimed in claim 5 characterized in that the guide tubes adjacent the side borders of the bottom part are shorter than the remaining guide tubes.
Claim 9
Dependent Claim
19 words
A fuel assembly as claimed in claim 1 wherein the fuel rod tops terminate below the upper end fitting.
Claim 10
Dependent Claim
106 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving guide tubes and supporting in spaced parallel relation a plurality of separable upright fuel rods, said upper end fitting comprising separable top and bottom parts and being removably connected to the guide tubes and separable from the guide tubes and fuel rods enabling individual fuel rod removal from the assembly, the top part of the upper end fitting being generally annular with a depending skirt portion engaging the end of said bottom part.
Claim 11
Dependent Claim
106 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving guide tubes and supporting in spaced parallel relation a plurality of separable upright fuel rods, said upper end fitting comprising separable top and bottom parts and being removably connected to the guide tubes and separable from the guide tubes and fuel rods enabling individual fuel rod removal from the assembly, the top part of the upper end fitting being generally annular with a depending skirt portion engaging the end of said bottom part.
Claim 12
Dependent Claim
26 words
A fuel assembly as claimed in claim 8 characterized in that bolts removable from the top secure the said top part to the said bottom part.
Claim 13
Dependent Claim
118 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving guide tubes and supporting in spaced parallel relation a plurality of separable upright fuel rods, said upper end fitting comprising separable top and bottom parts and being removably connected to the guide tubes and separable from the guide tubes and fuel rods enabling individual fuel rod removal from the assembly, fastening means removable from the top and joining the top and bottom parts of the upper end fitting, and fastening means removable from the top and securing the said bottom part to the guide tubes.
Claim 14
Dependent Claim
118 words
A fuel assembly for a nuclear reactor, comprising an open support frame having vertically spaced upper and lower end fittings and intermediate grid spacers joined to a plurality of spaced parallel upright control-rod-receiving guide tubes and supporting in spaced parallel relation a plurality of separable upright fuel rods, said upper end fitting comprising separable top and bottom parts and being removably connected to the guide tubes and separable from the guide tubes and fuel rods enabling individual fuel rod removal from the assembly, fastening means removable from the top and joining the top and bottom parts of the upper end fitting, and fastening means removable from the top and securing the said bottom part to the guide tubes.
Claim 15
Dependent Claim
44 words
A fuel assembly as set forth in claim 10 wherein the removable fastening means for the guide tubes are located within a space formed between the top and bottom parts, and the top part forms a recess along its edge for receiving a grapple.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |