US4762671A
Expired / Lapsed
US
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Injection device
Assignee: Toshiba Corp
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Filing: 1987-01-14
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Granted: 1988-08-09
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Expires: 2007-01-14
Abstract
Abstract Injection device used when a reactor is shut down to remove radioactive substances from within the gap between the internal piping and the inside of the nozzles of a RPV by injecting fluid towards the inside of these nozzles. The injection device is equipped with an injection nozzle that injects fluid towards the end of the gap, a casing that supports this injection nozzle, a suspension mechanism whereby the casing is movably suspended from above the RPV, a water feed device that supplies high-pressure fluid to the injection nozzle, a sensor or the like that senses when the casing is positioned directly above the internal piping and a fixing mechanism that temporarily fixes the casing to the inside wall of the RPV.
Inventors
- 👤 Masahiro Kobayashi
- 👤 Masaru Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:56
CPC Classifications
G; G21; G21C; G21C17/00; G21C17/003; G21C19/00; G21C19/28; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
185 words
In a nuclear reactor pressure vessel having a cylindrical side wall with an interior surface, at least one nozzle penetrating said side wall, piping penetrating said side wall at said nozzle, said nozzle and said piping forming an annular gap at said interior surface of said side wall, and means for decontaminating said reactor pressure vessel at said annular gap, said means for decontaminating comprising: a casing; means for suspending said casing in the reactor pressure vessel from a position above the reactor pressure vessel, whereby said casing can be positioned adjacent to the gap; at least one injection nozzle arranged at a positive dip angle in said casing means for supplying high-pressure liquid to said at least one injection nozzle; means mounted on said casing for detecting that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap; and means for selectively fixing said casing to the reactor pressure vessel when said detecting means detects that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap.
Claim 2
Dependent Claim
185 words
In a nuclear reactor pressure vessel having a cylindrical side wall with an interior surface, at least one nozzle penetrating said side wall, piping penetrating said side wall at said nozzle, said nozzle and said piping forming an annular gap at said interior surface of said side wall, and means for decontaminating said reactor pressure vessel at said annular gap, said means for decontaminating comprising: a casing; means for suspending said casing in the reactor pressure vessel from a position above the reactor pressure vessel, whereby said casing can be positioned adjacent to the gap; at least one injection nozzle arranged at a positive dip angle in said casing means for supplying high-pressure liquid to said at least one injection nozzle; means mounted on said casing for detecting that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap; and means for selectively fixing said casing to the reactor pressure vessel when said detecting means detects that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap.
Claim 3
Dependent Claim
23 words
Means for decontaminating according to claim 1, wherein said at least one injection nozzle is formed as a slit elongated along said gap.
Claim 4
Dependent Claim
16 words
Means for decontaminating according to claim 1, wherein said dip angle is between 0° and 45°.
Claim 5
Dependent Claim
22 words
Means for decontaminating according to claim 1, wherein said means for selectively fixing comprises at least one electromagnet fixed to said casing.
Claim 6
Dependent Claim
18 words
Means for decontaminating according to claim 1, wherein said means for detecting comprises at least one touch sensor.
Claim 7
Dependent Claim
42 words
Means for decontaminating according to claim 1, wherein said casing includes a vertically extending groove extending over the entirety of a surface of said casing, whereby said casing can avoid interferring with an obstacle projecting from the reactor pressure vessel side wall.
Claim 8
Dependent Claim
28 words
Means for decontaminating according to claim 1, wherein said means for supplying high-pressure liquid comprises means for supplying at least 0.2 m 3 /hr of said high-pressure liquid.
Claim 9
Dependent Claim
66 words
Means for decomtaminating according to claim 1, wherein said at least one injection nozzle is positioned on said casing so as to be spaced from a vertical plane passing through an axis of the reactor pressure vessel by an arcuate angle of no more than 7.5° when said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap.
Claim 10
Dependent Claim
34 words
Means for decontaminating according to claim 1, comprising at least two of said injection nozzles and further comprising means for selectively supplying high pressure liquid to only one of said nozzles at a time.
Claim 11
Dependent Claim
52 words
Means for decontaminating according to claim 4, in combination with a reactor pressure vessel having a low alloy steel matrix with a 5 mm thick internal lining of austenitic stainless steel, wherein each said at least one electromagnet has an electromagnetic coil with a diameter of between 80 mm and 90 mm.
Claim 12
Dependent Claim
192 words
In a nuclear reactor pressure vessel having a cylindrical side wall with an interior surface, at least one nozzle penetrating said side wall, piping penetrating said side wall at said nozzle, said nozzle and said piping forming an annular gap at said interior surface of said side wall, and means for decontaminating said reactor pressure vessel at said annular gap, said means for decontaminating comprising: a casting; means for suspending said casing in the reactor pressure vessel from a position above the reactor pressure vessel, whereby said casing can be positioned adjacent to the gap; at least one injection nozzle arranged in said casing; means for supplying high-pressure liquid to said at least one injection nozzle; means mounted on said casing for detecting that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap; and means for selectively fixing said casing to the reactor pressure vessel when said detecting means detects that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap, said fixing means comprising at least one electromagnet fixed to said casing.
Claim 13
Dependent Claim
192 words
In a nuclear reactor pressure vessel having a cylindrical side wall with an interior surface, at least one nozzle penetrating said side wall, piping penetrating said side wall at said nozzle, said nozzle and said piping forming an annular gap at said interior surface of said side wall, and means for decontaminating said reactor pressure vessel at said annular gap, said means for decontaminating comprising: a casting; means for suspending said casing in the reactor pressure vessel from a position above the reactor pressure vessel, whereby said casing can be positioned adjacent to the gap; at least one injection nozzle arranged in said casing; means for supplying high-pressure liquid to said at least one injection nozzle; means mounted on said casing for detecting that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap; and means for selectively fixing said casing to the reactor pressure vessel when said detecting means detects that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap, said fixing means comprising at least one electromagnet fixed to said casing.
Claim 14
Dependent Claim
23 words
Means for decontaminating according to claim 11, wherein said at least one injection nozzle is formed as a slit elongated along said gap.
Claim 15
Dependent Claim
18 words
Means for decontaminating according to claim 11, wherein said means for detecting comprises at least one touch sensor.
Claim 16
Dependent Claim
42 words
Means for decontaminating according to claim 11, wherein said casing includes a vertically extending groove extending over the entirety of a surface of said casing, whereby said casing can avoid interferring with an obstacle projecting from the reactor pressure vessel side wall.
Claim 17
Dependent Claim
188 words
In a nuclear reactor pressure vessel having a cylindrical side wall with an interior surface, at least one nozzle penetrating said side wall, piping penetrating said side wall at said nozzle, said nozzle and said piping forming an annular gap at said interior surface of said side wall, and means for decontaminating said nuclear reactor vessel at said annular gap, said means for decontaminating comprising: a casing; means for suspending said casing in the reactor vessel from a position above the reactor pressure vessel, whereby said casing can be positioned adjacent to the gap; at least one injection nozzle arranged in said casing; means mounted on said casing for supplying high-pressure liquid to said at least one injection nozzle; means for detecting that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap, said detecting means comprising at least one tough sensor; and means for selectively fixing said casing to the reactor pressure vessel when said detecting means detect that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap.
Claim 18
Dependent Claim
188 words
In a nuclear reactor pressure vessel having a cylindrical side wall with an interior surface, at least one nozzle penetrating said side wall, piping penetrating said side wall at said nozzle, said nozzle and said piping forming an annular gap at said interior surface of said side wall, and means for decontaminating said nuclear reactor vessel at said annular gap, said means for decontaminating comprising: a casing; means for suspending said casing in the reactor vessel from a position above the reactor pressure vessel, whereby said casing can be positioned adjacent to the gap; at least one injection nozzle arranged in said casing; means mounted on said casing for supplying high-pressure liquid to said at least one injection nozzle; means for detecting that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap, said detecting means comprising at least one tough sensor; and means for selectively fixing said casing to the reactor pressure vessel when said detecting means detect that said at least one injection nozzle is positioned such that high-pressure liquid therefrom may be injected into the gap.
Claim 19
Dependent Claim
23 words
Means for decontaminating according to claim 15, wherein said at least one injection nozzle is formed as a slit elongated along said gap.
Claim 20
Dependent Claim
42 words
Means for decontaminating according to claim 15, wherein said casing includes a vertically extending groove extending over the entirety of a surface of said casing, whereby said casing can avoid interferring with an obstacle projecting from the reactor pressure vessel side wall.
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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) | 1991-08-09 | 1992-02-08 | 1992-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-09 | 1996-02-08 | 1996-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-09 | 2000-02-08 | 2000-08-09 | $7700.00 | Window Closed / Lapsed |