US3857755A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel pin securing apparatus
Assignee: Boeing North American Inc
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Filing: 1971-03-11
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Granted: 1974-12-31
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Expires: 1991-03-11
Abstract
Abstract A fuel pin hold-down and spacing apparatus for use in nuclear reactors is disclosed. Fuel pins forming a hexagonal array are spaced apart from each other and held-down at their lower end, securely attached at two places along their length to one of a plurality of vertically disposed parallel plates arranged in horizontally spaced rows. These plates are in turn spaced apart from each other and held together by a combination of spacing and fastening means. The arrangement of this invention provides a strong vibration free hold-down mechanism while avoiding a large pressure drop to the flow of coolant fluid. This apparatus is particularly useful in connection with liquid cooled reactors such as liquid metal cooled fast breeder reactors.
Inventors
- 👤 J Kinzer
- 👤 M Fallandy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:52
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C3/33; G21C3/3305; G21C3/331; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
169 words
A fuel element assembly for use in nuclear reactors comprising an elongated hexagonal, vertically-oriented metallic housing, a bundle of elongated, cylindrical fuel-containing rods disposed in a triangular array within said housing, including parallel rows of rods extending lengthwise of said housing, each of said cylindrical fuel rods having at its lower end a solid portion, said solid portion having a section partially cut away from the exterior periphery thereof so as to form an outwardly facing flat vertical surface on the remaining part of said solid portion, said remaining part having a thickness greater than onehalf the original thickness of said solid portion, spacer strips extending the length of said rows and attached to each of said rods in said rows at a plurality of locations along the length of said outwardly facing flat vertical surface, means to hold said strips in a predetermined spaced relationship in a direction normal to said rows, and means to hold said strips at a predetermined position along the length of said housing.
Claim 2
Dependent Claim
169 words
A fuel element assembly for use in nuclear reactors comprising an elongated hexagonal, vertically-oriented metallic housing, a bundle of elongated, cylindrical fuel-containing rods disposed in a triangular array within said housing, including parallel rows of rods extending lengthwise of said housing, each of said cylindrical fuel rods having at its lower end a solid portion, said solid portion having a section partially cut away from the exterior periphery thereof so as to form an outwardly facing flat vertical surface on the remaining part of said solid portion, said remaining part having a thickness greater than onehalf the original thickness of said solid portion, spacer strips extending the length of said rows and attached to each of said rods in said rows at a plurality of locations along the length of said outwardly facing flat vertical surface, means to hold said strips in a predetermined spaced relationship in a direction normal to said rows, and means to hold said strips at a predetermined position along the length of said housing.
Claim 3
Dependent Claim
52 words
A fuel element according to claim 1 wherein said means to hold said strips at a predetermined position along the length of said housing comprises a plurality of connecting rods which pass through said strips at a direction normal to said strips and which are attached at their ends to said housing.
Claim 4
Dependent Claim
37 words
The fuel element of claim 2 wherein said connecting rods are surrounded with a plurality of spacers individually disposed in abutting relationship to said strips whereby each of said strips has a spacer on each side thereof.
Claim 5
Dependent Claim
47 words
The fuel element assembly of claim 1 wherein each of said fuel rods contain a plurality of stud portions spaced along and extending from said flat vertical surface and wherein each of said stud portions is adapted to be received within corresponding holes in said spacer strips.
Claim 6
Dependent Claim
42 words
The fuel element assembly of claim 4 wherein said stud portions are hollow at their projecting ends, extending through said holes in said spacer strips and are deformed at their ends thereby forming a rigid attachment of said pins to said strip.
Claim 7
Dependent Claim
16 words
The fuel element assembly of claim 4 wherein each of said pins contains two stud portions.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |