US3886037A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nuclear fuel pin controlled failure device
Assignee: United States Department of Energy
•
Filing: 1973-08-17
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Granted: 1975-05-27
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Expires: 1993-08-17
Abstract
Abstract Each fuel pin of a fuel assembly for a water-cooled nuclear reactor is provided with means for rupturing the cladding tube thereof at a predetermined location if an abnormal increase in pressure of the gases present therein occurs due to a loss-ofcoolant accident. Preferably all such rupture means are oriented to minimize the hydraulic resistance to the flow of emergency core coolant such as all rupture means pointing in the same direction. Rupture means may be disposed at different elevations in adjacent fuel pins and, further, fuel pins may be provided with two or more rupture means, one of which is in the upper portion of the fuel pin. Rupture means are mechanical as by providing a locally weakened condition of a controlled nature in the cladding.
Inventors
- 👤 Larry D Schlenker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:36
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C9/00; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
94 words
A FUEL ASSEMBLY FOR A WATER-COOLED NUCLEAR REACTOR INCLUDING A PLURALITY OF PARALLEL, SLENDER ELONGATED FUEL PINS HELD TOGETHER IN SQUARE ARRAY TO FORM A FUEL BUNDLE, SAID FUEL PINS CONTAINING NUCLEAR FUEL HERMETICALLY SEALED WITH A CLADDING TUBE AND INCLUDING MEANS ASSOCIATED WITH SAID CLADDING TUBES FOR RUPTURING THE CLADDING TUBES AT A PREDETERMINED LOCATION SAID MEANS FOR RUPTURING THE CLADDING TUBES BEING ALL ORIENTED IN THE SAME AZIMUTHAL DIRECTION WITHIN THE FUEL BUNDLE WHEREBY HYDRAULIC RESISTANCE TO THE FLOW OF EMERGENCY CORE COOLANT WILL BE MINIMIZED IN THE EVENT A LOSS-OF-COOLANT ACCI-
Claim 2
Dependent Claim
94 words
A FUEL ASSEMBLY FOR A WATER-COOLED NUCLEAR REACTOR INCLUDING A PLURALITY OF PARALLEL, SLENDER ELONGATED FUEL PINS HELD TOGETHER IN SQUARE ARRAY TO FORM A FUEL BUNDLE, SAID FUEL PINS CONTAINING NUCLEAR FUEL HERMETICALLY SEALED WITH A CLADDING TUBE AND INCLUDING MEANS ASSOCIATED WITH SAID CLADDING TUBES FOR RUPTURING THE CLADDING TUBES AT A PREDETERMINED LOCATION SAID MEANS FOR RUPTURING THE CLADDING TUBES BEING ALL ORIENTED IN THE SAME AZIMUTHAL DIRECTION WITHIN THE FUEL BUNDLE WHEREBY HYDRAULIC RESISTANCE TO THE FLOW OF EMERGENCY CORE COOLANT WILL BE MINIMIZED IN THE EVENT A LOSS-OF-COOLANT ACCI-
Claim 3
Dependent Claim
21 words
Fuel assembly according to claim 1 wherein the means for rupturing the cladding tubes are rupture slots in said cladding tubes.
Claim 4
Dependent Claim
32 words
Fuel assembly according to claim 2 wherein said rupture means are constituted of cladding material which is mechanically weaker at the point rupture is desired than the remainder of the cladding material.
Claim 5
Dependent Claim
26 words
Fuel assembly according to claim 3 wherein the cladding tube is thinner at the point rupture is dEsired than in the remainder of the cladding tube.
Claim 6
Dependent Claim
19 words
Fuel assembly according to claim 4 wherein the rupture means on adjacent fuel pins are disposed at different elevations.
Claim 7
Dependent Claim
31 words
Fuel assembly according to claim 5 wherein at least some of the fuel pins include two rupture means, one of which is located in the upper portion of the fuel pin.
Claim 8
Dependent Claim
46 words
Fuel assembly according to claim 5 wherein the nuclear fuel is slightly enriched uranium dioxide, the cladding tube is made of zirconium alloy, the cladding tube is normally 0.025 to 0.035 inches thick and the cladding has been locally thinned at the point rupture is desired.
Claim 9
Dependent Claim
42 words
Fuel assembly according to claim 1 wherein the active length of the nuclear fuel is 12 feet and each fuel pin includes two rupture means, one of which is in the upper four feet of the active length of the nuclear fuel.
References Cited (Backward Citations)
US3719560A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |