US3816247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nuclear fuel assembly, especially for a fast reactor
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1972-05-30
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Granted: 1974-06-11
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Expires: 1992-05-30
Abstract
Abstract The fuel assembly comprises at least one bundle of parallel fuel pins disposed on a uniform lattice within a pressure-resistant outer prismatic sleeve which has a polygonal cross-section and through which a coolant is circulated. Curvature of the sleeve produced by swelling under intense irradiation is limited by means of slots which are cut across the dihedrons formed by the sleeve faces. A thin-walled jacket which guides the coolant flow within the fuel bundle and withstands vertical handling stresses is placed between the bundle and the sleeve with provision for a clearance which permits expansion of the jacket under the action of differential pressure.
Inventors
- 👤 A Cayol
- 👤 J Chenal
- 👤 J Skok
- 👤 H Venobre
- 👤 G Clottes
- 👤 K Schaller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:34
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C3/324; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
130 words
A nuclear fuel assembly consisting of at least one bundle of canned-fuel pins of substantial length, said pins being disposed in parallel relation on a uniform lattice, a sleeve in the form of a prismatic casing having a polygonal transverse cross-section which contains said bundle and carries a circulation of cooling fluid, a bottom end fitting secured to said casing, a handling head secured to said casing, slots in the dihedrons formed by the faces of the sleeve casing and an internal jacket of smaller thickness than the sleeve between said sleeve and the bundle of fuel pins and secured to said bottom end fitting and to said handling head, the ratio of the thickness of the sleeve to the thickness of the internal jacket being between 3.5:1 and 2:1.
Claim 2
Dependent Claim
130 words
A nuclear fuel assembly consisting of at least one bundle of canned-fuel pins of substantial length, said pins being disposed in parallel relation on a uniform lattice, a sleeve in the form of a prismatic casing having a polygonal transverse cross-section which contains said bundle and carries a circulation of cooling fluid, a bottom end fitting secured to said casing, a handling head secured to said casing, slots in the dihedrons formed by the faces of the sleeve casing and an internal jacket of smaller thickness than the sleeve between said sleeve and the bundle of fuel pins and secured to said bottom end fitting and to said handling head, the ratio of the thickness of the sleeve to the thickness of the internal jacket being between 3.5:1 and 2:1.
Claim 3
Dependent Claim
25 words
A fuel assembly according to claim 1, wherein the slots are aligned on a helix and each cut at least one dihedron of the sleeve.
Claim 4
Dependent Claim
21 words
A fuel assembly according to claim 2, wherein the slots form a continuous line and the sleeve is a continuous strip.
Claim 5
Dependent Claim
49 words
A fuel assembly according to claim 1, wherein the slots are distributed in a plurality of sets spaced along the axis of said assembly, the slots forming part of one set being parallel at the same level and each cutting at least one of the dihedrons of the sleeve.
Claim 6
Dependent Claim
34 words
A fuel assembly according to claim 4, wherein the slots forming part of one set have an inclination to the axis opposite to the inclination of the slots forming part of an adjacent set.
Claim 7
Dependent Claim
34 words
A fuel assembly according to claim 1, wherein the sleeve is cut into sections by the slots located at right angles to the axis and extending over the entire transverse cross-section of said sleeve.
Claim 8
Dependent Claim
19 words
A fuel assembly according to claim 1 wherein the sleeve and the internal jacket are of austenitic stainless steel.
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) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |