US3801441A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Failed nuclear reactor fuel detection apparatus
Assignee: UNC NUCLEAR INDUSTRIES Inc A CORP OF
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Filing: 1971-10-12
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Granted: 1974-04-02
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Expires: 1991-10-12
Abstract
Abstract Apparatus for detecting failed or leaking fuel rods in fuel assemblies in a nuclear reactor for power generation are described. A gripper for the fuel assembly is combined with a sampling tube for sucking up a coolant sample after the temperature of the fuel rods has been increased to a level causing increased emission of radioactive residues from a leaking rod. For the BWR, the gripper couples to the fuel assembly channel while in the reactor core in such manner as to isolate in a substantially air-tight manner the fuel assembly. Then an air bubble is introduced depressing the coolant level causing the desired temperature increase. For the PWR, the gripper lifts the fuel assembly into an overhead container to isolate same, and then heat is supplied via axuiliary heaters to raise the temperature of the fuel rods. To increase the sensitivity, the coolant sample is taken from below the upper fuel rod support.
Inventors
- 👤 C Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:02
CPC Classifications
G; G21; G21C; G21C17/00; G21C17/02; G21C17/04; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
173 words
Apparatus for testing at least one fuel assembly of a BWR while surrounded by coolant in the reactor core for the presence of leaking fuel rods, said fuel assembly comprising a channel having an upstanding peripheral edge portion and an uppEr tie plate for supporting the upper ends of an assembly of fuel rods and also containing openings free of the fuel rods; comprising gripper means comprising an outer member which is substantially air-tight and having a depending lower edge portion dimensioned to mate with and substantially seal to the upstanding peripheral edge portion of the channel forming with the latter a container which is substantially air-tight, means coupled to the outer member for selectively locking to the fuel assembly channel, means for introducing an air bubble into the container for depressing the coolant level causing the temperature of the fuel rods to rise, and means for introducing a sampling tube through the outer member and through the tie plate opening for removing a sample of coolant disposed beneath the upper tie plate.
Claim 2
Dependent Claim
173 words
Apparatus for testing at least one fuel assembly of a BWR while surrounded by coolant in the reactor core for the presence of leaking fuel rods, said fuel assembly comprising a channel having an upstanding peripheral edge portion and an uppEr tie plate for supporting the upper ends of an assembly of fuel rods and also containing openings free of the fuel rods; comprising gripper means comprising an outer member which is substantially air-tight and having a depending lower edge portion dimensioned to mate with and substantially seal to the upstanding peripheral edge portion of the channel forming with the latter a container which is substantially air-tight, means coupled to the outer member for selectively locking to the fuel assembly channel, means for introducing an air bubble into the container for depressing the coolant level causing the temperature of the fuel rods to rise, and means for introducing a sampling tube through the outer member and through the tie plate opening for removing a sample of coolant disposed beneath the upper tie plate.
Claim 3
Dependent Claim
30 words
Apparatus as set forth in claim 1 wherein the channel peripheral edge portion comprises a bevelled edge, and the gripper outer member lower edge portion also comprises a bevelled edge.
Claim 4
Dependent Claim
49 words
Apparatus as set forth in claim 2 wherein the outer member comprises depending fingers having lateral extensions for engaging recesses in the channel walls, means supporting the fingers for lateral movement relative to the outer member, and means for actuating the fingers selectively to engage and disengage the recesses.
Claim 5
Dependent Claim
48 words
Apparatus as set forth in claim 1 wherein the sampling tube introducing means comprises a guide tube extending through the gripper from the outer member wall to the vicinity of the channel and provided with means for sealing to the sampling tube when the latter is passed therethrough.
Claim 6
Dependent Claim
40 words
Apparatus as set forth in claim 1 and further comprising means for lowering and raising the gripper relative to the fuel assembly, a sampling tube support, and means for raising and lowering the sampling tube support relative to the gripper.
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 |