US4394346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water level gauge for a nuclear reactor
Assignee: Toshiba Corp
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Filing: 1980-12-12
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Granted: 1983-07-19
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Expires: 2000-12-12
Abstract
Abstract A water level gauge for a nuclear reactor includes heat conduction means for absorbing and conducting heat to the outside of the drywell, the heat being supplied to reference water head water inside a reference water head tube defining a reference water level inside a reference water level container, and to water inside a lower part pressure pipe connecting a nuclear reactor pressure vessel with a differential pressure detector. The water level gauge further includes heat exchanger for removing the heat. With this device, the water level of the nuclear reactor may be correctly detected even in the case of leakage accident of the coolant of the nuclear reactor.
Inventors
- 👤 Shinichi Morooka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:17
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
186 words
A water level gauge for a nuclear reactor having a reference water level container communicating with a fluid in the upper part of a nuclear reactor pressure vessel through an upper part pressure tube, a differential pressure detector with two inlets for detecting a differential pressure between the reference water level in the reference water level container and the water level inside the nuclear reactor pressure vessel, a reference water head tube connecting one of said two inlets of the differential pressure detector with the reference water level container, and a lower part pressure tube connecting the other inlet of the differential pressure detector with a predetermined measuring point of part of the nuclear reactor pressure vessel, characterized by further comprising heat conduction means for absorbing heat from the reference water head water inside said reference water head tube and from the water inside said lower part pressure tube and for conducting the heat to the outside of a housing of the nuclear reactor pressure vessel, and a heat exchanger for removing the heat conducted to the outside of the housing by said heat conduction means.
Claim 2
Dependent Claim
186 words
A water level gauge for a nuclear reactor having a reference water level container communicating with a fluid in the upper part of a nuclear reactor pressure vessel through an upper part pressure tube, a differential pressure detector with two inlets for detecting a differential pressure between the reference water level in the reference water level container and the water level inside the nuclear reactor pressure vessel, a reference water head tube connecting one of said two inlets of the differential pressure detector with the reference water level container, and a lower part pressure tube connecting the other inlet of the differential pressure detector with a predetermined measuring point of part of the nuclear reactor pressure vessel, characterized by further comprising heat conduction means for absorbing heat from the reference water head water inside said reference water head tube and from the water inside said lower part pressure tube and for conducting the heat to the outside of a housing of the nuclear reactor pressure vessel, and a heat exchanger for removing the heat conducted to the outside of the housing by said heat conduction means.
Claim 3
Dependent Claim
20 words
A water level gauge according to claim 1, wherein said heat conduction means are covered with a heat insulating material.
Claim 4
Dependent Claim
59 words
A water level gauge according to claim 1 or 2, wherein said heat conduction means are heat pipes wound around said reference water head tube and said lower part pressure tube, said heat pipes comprising metal pipes, a porous material laminated on the inner walls of said matal pipes and a heat conducting material impregnated in said porous material.
Claim 5
Dependent Claim
66 words
A water level gauge according to claim 1 or 2, wherein said heat conduction means comprise sealed heat transfer pipes which are coaxially arranged around said reference water head tube and said lower part pressure tube and in which a working fluid is sealed, and slanted tubes which open from the upper parts of said thermosiphon tubes and reach said heat exchangers at an upward slant.
Claim 6
Dependent Claim
37 words
A water level gauge according to claim 1 or 2, wherein said heat conduction means comprise casings covering said reference water head tube and said lower part pressure tube, and cooling water forcibly circulated within said casings.
References Cited (Backward Citations)
US3031887A
Cited
US3250123A
Cited
US3898467A
Cited
US3979958A
Cited
US3969942A
Cited
US4216821A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-18 | 1987-01-17 | 1987-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-18 | 1991-01-17 | 1991-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-18 | 1995-01-17 | 1995-07-19 | $7700.00 | Window Closed / Lapsed |