JPS6041757B2 - Leak detection equipment in nuclear power plants - Google Patents
Leak detection equipment in nuclear power plantsInfo
- Publication number
- JPS6041757B2 JPS6041757B2 JP50019864A JP1986475A JPS6041757B2 JP S6041757 B2 JPS6041757 B2 JP S6041757B2 JP 50019864 A JP50019864 A JP 50019864A JP 1986475 A JP1986475 A JP 1986475A JP S6041757 B2 JPS6041757 B2 JP S6041757B2
- Authority
- JP
- Japan
- Prior art keywords
- video
- infrared
- moisture
- nuclear power
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Monitoring And Testing Of Nuclear Reactors (AREA)
Description
【発明の詳細な説明】
本発明は原子力発電所における高温高圧蒸気等の漏洩検
出装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a leak detection device for high-temperature, high-pressure steam, etc. in a nuclear power plant.
一般に、原子力発電所は、すべて配管、弁、ポンプ、タ
ンク、槽などの機器で構成されており、これ等の構成機
器に不具合があると高温高圧の蒸気や放射性廃液等が漏
洩する。Generally, a nuclear power plant is made up of equipment such as piping, valves, pumps, tanks, and tanks, and if any of these components malfunction, high-temperature, high-pressure steam, radioactive waste liquid, etc. will leak.
そこで、従来は第１図に示す如く、原子炉格納建物１内
において高温高圧の蒸気漏洩は温度検出器４と圧力検出
器２によつて、配管の破断による流量の変化は差圧器３
によつて、放射性ガスの漏洩は放射能検出器５によつて
、放射性液体の漏洩はこれをドレイン収集槽８か建屋の
区切部の床９に貯めて水位計６、７によつてそれぞれ検
出して漏洩があると警報装置１０が警報を発している。
（なお、タービン発電機建屋１１内においても同様の検
出をしているが、ここでは説明を省略する。）ところが
、原子力発電所は超大型てあり、かノつ、機器等の設備
の構成が複雑である。中でも、配管系統は原子炉格納建
物内において多数、しかも縦横に配設されているため、
きわめて複雑な構成となつている。そのため、上記検出
器の設置が難しく、また、漏洩の発生湯所の特定が困難
であり、その結果漏洩検出が概略的にならざるを得ず、
従来の方法では微少な漏洩ならびにその発生位置を正確
に検出することができなかつた。また、一旦放射性液の
漏洩事故が発生した場合、被爆防止上の理由から原子炉
格納建物内に作業者が立入ることは好ましくない。した
がつて、かかる複雑な配管系のどの部分に漏洩が生じた
かを検出することがきわめて困難であつた。本発明は上
記点に鑑みなされたもので、微少な漏洩をも迅速に検出
する漏洩検出装置を提供することを目的とし、高温高圧
蒸気配管から発生する赤外線の変化を赤外線用テレビカ
メラで捕え、かつ発電所内の複数個所に設置した湿分検
出器により漏洩蒸気ならびに放射性液体等の漏洩位置を
正確に検出するものである。Conventionally, as shown in Fig. 1, leaks of high-temperature, high-pressure steam inside the reactor containment building 1 are detected by a temperature detector 4 and a pressure detector 2, and changes in flow rate due to pipe rupture are detected by a differential pressure regulator 3.
Accordingly, leakage of radioactive gas is detected by a radioactivity detector 5, and leakage of radioactive liquid is detected by collecting it in a drain collection tank 8 or the floor 9 of a partitioned part of the building and detecting it by water level gauges 6 and 7, respectively. If there is a leak, the alarm device 10 issues an alarm.
(Similar detection is also carried out inside the turbine generator building 11, but the explanation is omitted here.) However, nuclear power plants are extremely large, and the configuration of equipment such as equipment is different. It's complicated. Among these, there are many piping systems installed in the reactor containment building, and they are arranged horizontally and vertically.
It has an extremely complex structure. Therefore, it is difficult to install the above-mentioned detector, and it is also difficult to identify the hot water area where the leak occurs, and as a result, leak detection has to be rough.
Conventional methods have not been able to accurately detect minute leaks and their locations. Furthermore, once a radioactive liquid leakage accident occurs, it is not desirable for workers to enter the reactor containment building for reasons of preventing exposure to radiation. Therefore, it has been extremely difficult to detect in which part of such a complicated piping system a leak has occurred. The present invention was made in view of the above points, and aims to provide a leakage detection device that can quickly detect even the smallest leakage. In addition, moisture detectors installed at multiple locations within the power plant accurately detect the locations of leaking steam and radioactive liquid.
以下、図面を参照して本発明の実施例を説明する。Embodiments of the present invention will be described below with reference to the drawings.
第２図に示すように、原子炉格納建物１内およびタービ
ン発電機物１１内に赤外線用テレビカメラ２１−１，２
１−２および湿分検出スイッチ２２−１〜２２−９を設
置する。設置位置は図の位置に限られるものではなく、
また設置台数も増やすことができる。ただし、第２図に
も示されているように、赤外線用テレビカメラ２１−１
，２１−２と湿分検出スイッチ２２−１〜２２−９後述
するように一定の相対位置関係を有している。赤外線用
テレビカメラ２１−１と２１−２は、高温高圧蒸気用配
管２５を広範囲に監視てきるように常時上下左右に周期
的に駆動されており、これらによつて捕えられた映像は
赤外線検出装置２４に送られる。赤外線検出装置２４は
、第３図に示すようにコントロールユニット２６、映像
記憶装置２７、映像比較器２８、異常警報装置２９、映
像モニタ３０、オシロスコープ３１、記録計３２、高温
警報装置３３とからなつている。赤外線用テレビカメラ
２１−１と２１−２は、あらかじめ高温高圧蒸気用配管
２５の正常状態を捕えて映像信号を発し、コントロール
ユニット２６はこの映像信号を映像記憶装置２７に記憶
させる。原子力発電所の運転中は、赤外線用テレビカメ
ラ２１一１と２１−２は当初設定された通りに上下左右
に周期的に駆動される。この間に配管２５から高温高圧
蒸気が漏洩するとその周辺部の温度が上昇して発熱状態
となり、そこから赤外線が放射する。赤外線テレビカメ
ラ２１−１（または２１−２）はこの赤外線を受けて映
像信号を発し、コントロールユニット２６はこれを映像
比較器２８に送出する。映像比較器２５はこの映像信号
と当初映像記憶装置２７に記憶された正常状態の映像信
号と比較して、異常検出器信号が発し、これに応じて異
常警報装置２９から警報が出されるとともに、上記異常
検出信号によりカメラ駆動部２１は赤外線用テレビカメ
ラ２１−１（または２１一２）はその位置に停止させ、
更に厳密に異常箇所を連続監視する。これにり、今度は
コントロールユニット２６から映像モニタ３０とオシロ
スコープ３１に映像信号が送られ、映像モニタ３０は異
常個所を克明に写し出し、オシロスコープ３１は、異常
箇所の温度状態を表示するとともに記録計３２にこの温
度状態を示す温度検出信号を発する。記録計３２はこの
温度を記録するとともに、これが設定値以上の場合には
高温検出器信号を高温警報装置３３に出力し、これに応
じて高温警報装置３３は警報を発する。湿分検出器２２
−１〜２２−９は第２図に示す如く原子炉格納建屋１お
よびタービン発電機建屋１１内の床面や壁部等に設置さ
れ、（湿分検出器の数はこれに限られるわけでなく必要
に応じて増減てきる）各々湿分検出漏洩表示装置２３に
接続される。As shown in FIG. 2, infrared television cameras 21-1 and 2 are installed inside the reactor containment building 1 and the turbine generator building 11.
1-2 and moisture detection switches 22-1 to 22-9 are installed. The installation location is not limited to the location shown in the diagram.
Also, the number of installed units can be increased. However, as shown in FIG. 2, the infrared television camera 21-1
, 21-2 and the moisture detection switches 22-1 to 22-9 have a certain relative positional relationship as will be described later. The infrared television cameras 21-1 and 21-2 are constantly periodically driven vertically and horizontally to monitor a wide range of the high-temperature, high-pressure steam pipe 25, and the images captured by these cameras are detected by infrared detection. is sent to device 24. As shown in FIG. 3, the infrared detection device 24 includes a control unit 26, a video storage device 27, a video comparator 28, an abnormality warning device 29, a video monitor 30, an oscilloscope 31, a recorder 32, and a high temperature warning device 33. ing. The infrared television cameras 21-1 and 21-2 capture the normal state of the high-temperature, high-pressure steam pipe 25 in advance and emit a video signal, and the control unit 26 stores this video signal in the video storage device 27. During operation of the nuclear power plant, the infrared television cameras 21-1 and 21-2 are periodically driven vertically and horizontally as originally set. During this time, when high-temperature, high-pressure steam leaks from the pipe 25, the temperature of the surrounding area rises and becomes exothermic, and infrared rays are emitted from there. The infrared television camera 21-1 (or 21-2) receives this infrared rays and emits a video signal, and the control unit 26 sends this to the video comparator 28. The video comparator 25 compares this video signal with the normal video signal originally stored in the video storage device 27, and an abnormality detector signal is generated, and in response to this, the abnormality alarm device 29 issues an alarm. In response to the abnormality detection signal, the camera drive unit 21 stops the infrared television camera 21-1 (or 21-2) at that position,
Furthermore, abnormal locations are continuously monitored. In turn, a video signal is sent from the control unit 26 to the video monitor 30 and oscilloscope 31, and the video monitor 30 clearly shows the abnormal location, and the oscilloscope 31 displays the temperature status of the abnormal location, and the recorder 32 A temperature detection signal indicating this temperature condition is then generated. The recorder 32 records this temperature and outputs a high temperature detector signal to the high temperature alarm device 33 when the temperature is higher than the set value, and in response, the high temperature alarm device 33 issues an alarm. Moisture detector 22
-1 to 22-9 are installed on the floors and walls of the reactor containment building 1 and the turbine generator building 11 as shown in Figure 2 (the number of moisture detectors is not limited to these). (increase or decrease as needed) are connected to the moisture detection leakage display device 23.
また、湿分検出器２２−１〜２２−９は、第２図に示す
ように、赤外線用テレビカメラ２１一１，２２−１の監
視範囲と一定の関係を有している。Further, the moisture detectors 22-1 to 22-9 have a certain relationship with the monitoring range of the infrared television cameras 21-1 and 22-1, as shown in FIG.
すなわち、赤外線用テレビカメラ２１−１の監視範囲内
には湿分検出スイッチ２２−１〜２２一５が存在してお
り、赤外線用テレビカメラ２１−２の監視範囲内には湿
分検出スイッチ２２−６〜２２−９が存在している。湿
分検出漏洩表示装置２３は、第４図に示す如く、漏洩位
置表示器３４−１〜３４−９、湿分警報器３５からなつ
ており、湿分検出器２２−１〜２２−９がそれぞれ漏洩
位置表示器３４−１〜３４−９に接続されてる。今、例
えは放射性廃液の漏洩があり、湿分検出器２２−１がこ
れを検出したとすると、湿分検出器２−１はそれ自身変
色するとともに湿分検出信号を発し、漏洩位置表示装置
３４−１はこれを受けて漏洩位置を表示するとともに湿
分警報信号を発し、湿分警報器３５はこれを受けて警報
を発する。なお、湿分検出器２２−１〜２２−９および
湿分検出漏洩表示装置２３は、冷却水の漏洩や高温高湿
蒸気の湿分等に関しても同様の動作をする。このように
、赤外線用テレビカメラ２１−１，２１−２を上下左右
に駆動させて所定の範囲における配管およびその他の機
器等からの漏洩を監視する、一方、各湿分検出スイッチ
２２−１〜２２−９により細部に亘る漏洩状態を検出し
てその漏洩個所が表示装置２３に表示される。That is, the moisture detection switches 22-1 to 22-5 exist within the monitoring range of the infrared television camera 21-1, and the moisture detection switches 22-5 exist within the monitoring range of the infrared television camera 21-2. -6 to 22-9 are present. As shown in FIG. 4, the moisture detection leakage display device 23 consists of leakage position indicators 34-1 to 34-9 and a moisture alarm 35. They are connected to leak position indicators 34-1 to 34-9, respectively. For example, if there is a leak of radioactive waste liquid and the moisture detector 22-1 detects this, the moisture detector 2-1 will change color and emit a moisture detection signal, and the leak position display device In response to this, the moisture alarm 34-1 displays the leak position and issues a moisture alarm signal, and the moisture alarm 35 receives this and issues an alarm. Note that the moisture detectors 22-1 to 22-9 and the moisture detection/leakage display device 23 perform similar operations regarding leakage of cooling water, moisture in high-temperature, high-humidity steam, and the like. In this way, the infrared television cameras 21-1 and 21-2 are driven vertically and horizontally to monitor leakage from piping and other equipment in a predetermined range, while each moisture detection switch 22-1 to 22-9 detects the leak state in detail and displays the leak location on the display device 23.
したがつて、赤外線用テレビカメラ２１−１，２１−２
の監視範囲が予め知られており、かつこれに対応する各
湿分検出スイッチ２２−１〜２２−９の設置位置も既知
のデータであることから、操作員は赤外線用テレビカメ
ラ２１−１，２１−２による原子炉格納建物１の空間中
に発生した漏洩情報と、各湿分検出スイッチ２２−１，
２２−９による細部に亘る漏洩情報とを得ることができ
、その結果、得られた２種類の漏洩情報により漏洩位置
を正確に知ることができるのである。また、通常、テレ
ビカメラのみによる監視の場合２次元方向の位置確認（
すなわち、上下又は左右）については比較的正確である
が、３次元方向（すなわち、奥行方向）の位置について
はあまり正確に検出し得ない。このことは、赤外線にて
行うテレビカメラにあつては、目視確認ができないので
一層問題となる。しかし、本発明によれば、かかる奥行
方向の精度の問題を多点配置した湿分検出スイッチ２２
−１，２２−９にて補償することができるという相乗効
果を奏することとなる。この実施例では、原子炉格納建
屋とタービン発電機建屋内の漏洩について設明したが、
本発明は原子力発電所内あるいはこれと同様の機能を有
する場所の漏洩をも検出できる。Therefore, infrared television cameras 21-1, 21-2
The monitoring range of the infrared television cameras 21-1, 22-9 is known in advance, and the corresponding installation positions of the moisture detection switches 22-1 to 22-9 are also known. 21-2, leakage information that has occurred in the space of the reactor containment building 1, and each moisture detection switch 22-1,
22-9, and as a result, the leak position can be accurately known from the two types of leak information obtained. In addition, when monitoring only with a TV camera, two-dimensional position confirmation (
That is, although it is relatively accurate in terms of vertical or horizontal directions, it is not possible to accurately detect a position in a three-dimensional direction (that is, in the depth direction). This becomes even more of a problem with television cameras that use infrared rays because visual confirmation is not possible. However, according to the present invention, the moisture detection switch 22 arranged at multiple points solves the problem of accuracy in the depth direction.
-1, 22-9 can be compensated for, resulting in a synergistic effect. In this example, leakage inside the reactor containment building and turbine generator building was specified.
The present invention can also detect leaks within a nuclear power plant or a location with similar functionality.
以上の説明から明らかな如く、本発明によれば、高温高
圧蒸気等の微少な漏洩ならびにその漏洩位置を迅速かつ
正確に検出でき、異常状態に対して早期に対処でき、発
電所の事故を未然に防止し得る。As is clear from the above description, according to the present invention, minute leaks of high-temperature, high-pressure steam, etc., as well as the leak positions can be detected quickly and accurately, abnormal conditions can be dealt with early, and accidents at power plants can be prevented. can be prevented.
第１図は従来の漏洩検出装置を示す説明図、第２図は本
発明の実施例を示す説明図、第３図および第４図はそれ
ぞれ本発明の実施例の一部を示すブロック図である。
１・・・・・・原子炉格納建屋、１１・・・・・・ター
ビン発電機建屋、２１−１，２１−２・・・・・・赤外
線用テレビカメラ、２１・・・・・・カメラ駆動部、２
２−１，２２−９・・・・・・湿分検出器、２３・・・
・・・湿分検出漏洩表示装置、２４・・・・・赤外線検
出装置、２５・・・・・・高温高圧蒸気用配管、２６・
・・・・・コントロールユニット、２７・・・・・映像
記憶装置、２８・・・・・・映像比較器、２９・・・・
・・異常警報装置、３０・・・・・・映像モニタ、３１
・・・・オシロスコープ、３２・・・・・・記録計、３
３・・高温警報装置、３４−１〜３４−９・・・・・・
漏洩位置表示装置、３５・・・・・・湿分警報装置。Fig. 1 is an explanatory diagram showing a conventional leak detection device, Fig. 2 is an explanatory diagram showing an embodiment of the present invention, and Figs. 3 and 4 are block diagrams each showing a part of the embodiment of the present invention. be. 1... Reactor containment building, 11... Turbine generator building, 21-1, 21-2... Infrared television camera, 21... Camera Drive unit, 2
2-1, 22-9...Moisture detector, 23...
... Moisture detection leakage display device, 24 ... Infrared detection device, 25 ... High temperature and high pressure steam piping, 26.
...Control unit, 27...Video storage device, 28...Video comparator, 29...
...Abnormality alarm device, 30...Video monitor, 31
...Oscilloscope, 32 ...Recorder, 3
3. High temperature alarm device, 34-1 to 34-9...
Leak position display device, 35...Moisture alarm device.
Claims (1)
高温高圧蒸気用配管から発生する赤外線の状態を捕えて
映像信号を発する、それぞれ監視範囲を有する複数の赤
外線用テレビカメラと、前記高温高圧蒸気用配管の正常
状態における赤外線の映像信号を記憶する映像記憶装置
と、前記赤外線用テレビカメラから送られる映像信号と
前記映像記憶装置に記憶された正常状態を示す映像信号
とを比較する映像比較器と、この映像比較器からの比較
結果出力を受けて異常である場合に警報を発する警報装
置と、前記赤外線用テレビカメラからの映像信号を受け
て異常個所の赤外線分布状態を映像表示する映像モニタ
と、原子炉格納建物およびタービン発電機建物内の複数
個所に、前記赤外線用テレビカメラの監視範囲ごとにそ
の監視範囲内に予め設置位置が明らかな状態で設置され
た湿分に反応する複数の湿分検出器と、前記湿分検出器
の検出出力を受けて湿分に反応した湿分検出器の設置位
置を表示する漏洩位置表示装置とを備えた原子力発電所
における漏洩検出装置。1. A plurality of infrared television cameras, each having its own monitoring range, that are constantly driven periodically up and down, left and right, and emit video signals by capturing the state of infrared rays generated from the high-temperature, high-pressure steam piping inside the nuclear power plant, and the high-temperature, high-pressure steam a video storage device that stores an infrared video signal in a normal state of the utility piping; and a video comparator that compares the video signal sent from the infrared television camera with the video signal stored in the video storage device that indicates the normal state. , an alarm device that receives the comparison result output from the video comparator and issues an alarm if there is an abnormality, and a video monitor that receives the video signal from the infrared television camera and displays a video of the infrared distribution state of the abnormal location. and a plurality of moisture-reacting cameras installed at multiple locations within the reactor containment building and the turbine generator building, with clear installation locations for each of the monitoring ranges of the infrared television cameras. A leak detection device in a nuclear power plant, comprising a moisture detector and a leak position display device that receives a detection output of the moisture detector and displays the installation position of the moisture detector that reacts to moisture.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP50019864A JPS6041757B2 (en) | 1975-02-19 | 1975-02-19 | Leak detection equipment in nuclear power plants |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP50019864A JPS6041757B2 (en) | 1975-02-19 | 1975-02-19 | Leak detection equipment in nuclear power plants |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5195597A JPS5195597A (en) | 1976-08-21 |
| JPS6041757B2 true JPS6041757B2 (en) | 1985-09-18 |
Family
ID=12011076
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP50019864A Expired JPS6041757B2 (en) | 1975-02-19 | 1975-02-19 | Leak detection equipment in nuclear power plants |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6041757B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0450362U (en) * | 1990-09-05 | 1992-04-28 |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59129805A (en) * | 1983-01-17 | 1984-07-26 | Hitachi Ltd | Visual equipment for gamma ray environment inspection |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1442195A (en) * | 1972-11-20 | 1976-07-07 | Westinghouse Electric Corp | Detection of leakage of fluid from nuclear reactor |
-
1975
- 1975-02-19 JP JP50019864A patent/JPS6041757B2/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0450362U (en) * | 1990-09-05 | 1992-04-28 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5195597A (en) | 1976-08-21 |
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