JP2868861B2 - Valve stem abnormality diagnosis device - Google Patents
Valve stem abnormality diagnosis deviceInfo
- Publication number
- JP2868861B2 JP2868861B2 JP2206748A JP20674890A JP2868861B2 JP 2868861 B2 JP2868861 B2 JP 2868861B2 JP 2206748 A JP2206748 A JP 2206748A JP 20674890 A JP20674890 A JP 20674890A JP 2868861 B2 JP2868861 B2 JP 2868861B2
- Authority
- JP
- Japan
- Prior art keywords
- valve
- valve stem
- abnormality
- stem
- ultrasonic
- 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 - Lifetime
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
- G01N29/07—Analysing solids by measuring propagation velocity or propagation time of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/028—Material parameters
- G01N2291/02854—Length, thickness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/04—Wave modes and trajectories
- G01N2291/044—Internal reflections (echoes), e.g. on walls or defects
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Description
【発明の詳細な説明】 〔発明の目的〕 （産業上の利用分野） 本発明は、発電プラント等に設置される弁装置におい
て、この弁装置を分解することなく、使用中に発生する
弁棒の割れ等の異常を診断することができるようにした
弁棒の異常診断装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a valve device installed in a power plant or the like, and a valve stem generated during use without disassembling the valve device. The present invention relates to a valve rod abnormality diagnosis device capable of diagnosing an abnormality such as a crack of a valve.
（従来の技術） 弁棒は、弁装置の構造上、その大部分が弁箱、弁蓋、
弁グランド部及び駆動装置内に収められており、これら
の内部に収められている部分については、外部から点検
を行うことができない。(Prior art) Due to the structure of the valve device, most of the valve stem is composed of a valve box, a valve lid,
It is housed in the valve gland and the drive unit, and the parts housed therein cannot be inspected from outside.
割れ等の異常が発生する可能性の高い弁棒の部位は、
その大半が上記のように外部から点検できない部分に含
まれている。The part of the valve stem where cracks and other abnormalities are likely to occur
Most of them are included in parts that cannot be inspected from outside as described above.
このため、従来の一般的な弁棒の点検は、ボルトを外
した後、弁蓋と弁箱とを分離し、弁箱内部にある弁棒に
対して表面より探傷検査を行うことによって行われてお
り、弁装置を分解する必要があった。For this reason, a conventional general inspection of a valve stem is performed by removing a bolt, separating a valve lid and a valve box, and performing a flaw inspection on the valve stem inside the valve box from the surface. And the valve device had to be disassembled.
（発明が解決しようとする課題） このように、従来弁棒の異常診断装置においては、弁
棒の点検を行うため、弁装置の分解を行う必要がある
が、この分解には、水抜き、多数あるボルト・ナットの
取外し、弁蓋の吊出し等の準備作業、検査用液の塗布及
び拭き取り等の検査作業、並びに弁装置の組立て及びそ
の後の水張り等の復旧作業に多大の手間暇がかかる。し
かも、これらの作業は、全て弁装置の近傍で行われるこ
とから、例えば原子力発電プラントの場合には、作業員
が被曝を受けるおそれがあるという課題があった。(Problems to be Solved by the Invention) As described above, in the conventional valve stem abnormality diagnosis device, it is necessary to disassemble the valve device in order to inspect the valve stem. Preparatory work such as removal of many bolts and nuts, lifting of the valve lid, inspection work such as application and wiping of test liquid, and assembling of the valve device and subsequent restoration work such as filling with water take a lot of time and labor. . Moreover, since all of these operations are performed in the vicinity of the valve device, there is a problem that, for example, in the case of a nuclear power plant, workers may be exposed.
本発明は上述した事情を考慮してなされたもので、弁
装置の分解作業を必要とすることなく、かつ超音波を利
用して弁棒に発生した割れ等の異常を点検できるように
した弁棒の異常診断装置を提供することを目的とする。The present invention has been made in consideration of the above-described circumstances, and does not require disassembly work of a valve device, and is capable of inspecting for abnormalities such as cracks generated in a valve stem using ultrasonic waves. An object of the present invention is to provide a rod abnormality diagnosis device.
（課題を解決するための手段） 本発明に係る弁棒の異常診断装置は、上述した課題を
解決するために、弁棒の先端に弁体を連結し、この弁体
を弁箱と弁蓋の間に昇降自在に配置し、上記弁体の昇降
によって前記弁箱と弁蓋の内部に位置する弁棒バックシ
ート部に発生する割れ等の異常を診断する弁棒の異常診
断装置において、弁棒に超音波を内部走査させる超音波
探触子を設置し、この超音波探触子からの超音波が前記
弁棒のバックシート部で反射して到達するまでの超音波
の到達時間を検出して弁棒の異常の有無を診断するもの
である。(Means for Solving the Problems) In order to solve the above-described problems, a valve stem abnormality diagnosis device according to the present invention connects a valve body to a tip of a valve stem, and connects the valve body to a valve box and a valve cover. A valve stem abnormality diagnostic device for diagnosing an abnormality such as a crack generated in a valve stem back seat portion located inside the valve box and the valve lid by the elevation of the valve body, An ultrasonic probe for internally scanning an ultrasonic wave on a rod is installed, and the arrival time of the ultrasonic wave from when the ultrasonic wave from the ultrasonic probe is reflected by the back sheet portion of the valve stem and reaches is detected. Then, the presence or absence of abnormality of the valve stem is diagnosed.
（作用） 弁棒の異常診断装置は上記のように構成したので弁棒
には全開位置で所定の引張荷重が負荷され、これによっ
て弁棒が若干伸びるとともに弁棒に軸力が発生し、この
ような状態では、弁棒の伸びと軸力による超音波の速度
変化により、反射後の超音波の到達時間が若干長くなる
が、弁棒に割れが発生しているか、または過大な負荷が
作用している場合には、弁棒は更に伸びるとともに、よ
り大きな軸力が発生して、超音波の到達時間が更に長く
なることになるので、この超音波の到達時間の変化を読
取ることにより、弁棒の異常の有無を診断することがで
きる。(Operation) Since the abnormality diagnosis device for the valve stem is configured as described above, a predetermined tensile load is applied to the valve stem at the fully opened position, whereby the valve stem is slightly extended and an axial force is generated on the valve stem. In such a state, the arrival time of the ultrasonic waves after reflection is slightly longer due to the change in the ultrasonic speed due to the elongation of the valve stem and the axial force, but the valve stem is cracked or an excessive load acts. In this case, the valve stem is further extended, and a larger axial force is generated, so that the arrival time of the ultrasonic wave becomes longer. By reading the change in the arrival time of the ultrasonic wave, It is possible to diagnose whether or not the valve stem is abnormal.
（実施例） 以下、本発明の実施例を図面を参照して説明する。(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.
第１図乃至第３図は、垂直探傷によって弁棒の異常を
診断する弁棒の異常診断装置の第１実施例を示すもの
で、例えば全閉位置をトルクシーティングにて制御する
弁装置の弁棒にあっては、弁棒バックシート部に割れが
発生する可能性が高い。FIGS. 1 to 3 show a first embodiment of a valve stem abnormality diagnosis device for diagnosing a valve stem abnormality by vertical flaw detection. For example, a valve of a valve device for controlling a fully closed position by torque sheeting is shown. In the case of a rod, there is a high possibility that a crack will occur in the valve stem backsheet portion.
この種の弁装置には、例えば第１図に示すように、弁
箱１と弁蓋２とが備えられ、両者1,2はボルト・ナット
３により結合されている。弁棒４は、駆動装置５からの
駆動力を弁体６に伝達するもので、弁棒４の下端に弁体
６が連結されている。弁体６は弁箱１と弁蓋２との間に
昇降自在に配置される。第３図に示すように、この弁箱
１と弁蓋２の内部に位置するバックシート部７に割れ８
が発生する可能性が高い。For example, as shown in FIG. 1, this type of valve device includes a valve box 1 and a valve cover 2, and both are connected by bolts and nuts 3. The valve stem 4 transmits the driving force from the driving device 5 to the valve body 6, and the valve body 6 is connected to the lower end of the valve stem 4. The valve element 6 is disposed between the valve box 1 and the valve cover 2 so as to be able to move up and down. As shown in FIG. 3, a crack 8 is formed in the back seat portion 7 located inside the valve box 1 and the valve cover 2.
Is more likely to occur.
そこで、このバックシート部７に割れ８が発生してい
るか否か等の弁棒４の異常有無の判断を以下のようにし
て行っている。Therefore, the determination as to whether or not the valve stem 4 is abnormal, such as whether or not the crack 8 has occurred in the back seat portion 7, is performed as follows.
第２図に詳細に示すように、弁棒４の頂部に超音波探
触子９を配置し、この超音波探触子９から出される超音
波を弁体６側に向かって垂直に弁棒４の内部を走査さ
せ、弁棒４の底面によって反射される超音波（底面エコ
ー）の到達時間を読取り、この到達時間が所定の時間よ
り長い場合には異常と判断するようなされている。As shown in detail in FIG. 2, an ultrasonic probe 9 is disposed on the top of the valve stem 4, and ultrasonic waves emitted from the ultrasonic probe 9 are vertically transmitted toward the valve 6. The inside of the valve 4 is scanned, the arrival time of the ultrasonic wave (bottom echo) reflected by the bottom surface of the valve stem 4 is read, and if the arrival time is longer than a predetermined time, it is determined that there is an abnormality.
この原理を第４図により説明する。 This principle will be described with reference to FIG.
通常の無負荷時（弁の中間開度位置）にあっては、第
４図（Ａ）に示すように、弁棒４に伸びや軸力が発生し
ていないフリーの状態にあるため、超音波探触子９から
出された超音波が弁棒４の底面で反射して超音波探触子
９に到達する超音波（底面エコー）の到達時間（エコー
到達時間）が最短となる。At the time of normal no-load (the intermediate opening position of the valve), as shown in FIG. 4 (A), the valve rod 4 is in a free state in which no expansion or axial force is generated. The arrival time (echo arrival time) of the ultrasonic wave (bottom echo) reaching the ultrasonic probe 9 after the ultrasonic wave emitted from the ultrasonic probe 9 is reflected on the bottom surface of the valve stem 4 is minimized.
これに比べ、第４図（Ｂ）に示すように、全開位置で
トルクシートした場合、弁棒４に伸びδ1が生じて軸力
が発生し、この伸びδ1と軸力の発生による超音波の速
度変化により、底面エコーのエコー到達時間が無負荷時
のフリー状態より時間Δｔだけ長くなる。In contrast, as shown in FIG. 4 (B), in the case where you torque sheets fully opened position, by axial force is generated by elongation [delta] 1 is generated in the valve rod 4, the elongation [delta] 1 and the axial force generating ultrasonic Due to the change in the speed of the sound wave, the arrival time of the bottom surface echo becomes longer by the time Δt than the free state when there is no load.
さらに、第４図（Ｃ）に示すように、弁棒４に割れ８
が発生しているか、または過大な負荷（軸力）が作用し
ている場合、弁棒４には、更に大きな伸びδ2（δ2＞δ
1）が生じるとともに、より大きな軸力が発生し、この
伸びδ2と軸力による超音波の速度変化により、底面エ
コーのエコー到達時間が上記フリーの状態より時間ΔＴ
だけ長くなり、この時間ΔＴは、上記割れや過大な負荷
が発生していない状態における時間Δｔよりも更に長く
なる（ΔＴ＞Δｔ）。なお、弁棒４に割れ８が発生して
いる場合、この割れ８からの反射波の検出により、割れ
の位置を検出することも可能である。Further, as shown in FIG.
Is generated, or when an excessive load (axial force) is acting, the valve stem 4 has a larger elongation δ 2 (δ 2 > δ).
1 ) occurs, and a larger axial force is generated. Due to the elongation δ 2 and a change in the speed of the ultrasonic wave due to the axial force, the echo arrival time of the bottom surface echo becomes longer than the free state by ΔT.
This time ΔT is further longer than the time Δt in the state where the crack and the excessive load are not generated (ΔT> Δt). When the crack 8 has occurred in the valve stem 4, the position of the crack can be detected by detecting the reflected wave from the crack 8.
そこで、この底面エコーのエコー到達時間の変化を読
取り、このエコー到達時間が所定の時間より長い場合に
弁棒４に割れ８等の異常があると判断する。これによ
り、弁棒４の割れ８や過大な負荷等の異常の有無を検知
することができる。Therefore, the change in the echo arrival time of the bottom surface echo is read, and if the echo arrival time is longer than a predetermined time, it is determined that the valve stem 4 has an abnormality such as a crack 8. This makes it possible to detect the presence or absence of an abnormality such as a crack 8 in the valve stem 4 or an excessive load.
第５図及び第６図は、斜角探傷によって弁棒の異常を
診断するようにした他の実施例を示すもので、弁装置の
全体の構成は第１実施例に示したものと異ならないので
同一符号を付して説明を省略する。FIGS. 5 and 6 show another embodiment in which an abnormality of a valve stem is diagnosed by oblique flaw detection, and the overall configuration of the valve device is not different from that shown in the first embodiment. Therefore, the same reference numerals are given and the description is omitted.
上記実施例と異なる点は、超音波探触子９を弁棒４の
側面（ヨーク部）に置き、この超音波探触子９から出さ
れ弁棒４の内周面で反射しつつ弁棒４の内部を走査され
る超音波の該超音波探触子９への到達時間（エコー到達
時間）を読取って、弁棒４の異常の有無を判断するよう
にしたものである。The difference from the above-described embodiment is that the ultrasonic probe 9 is placed on the side surface (yoke portion) of the valve stem 4 and is taken out of the ultrasonic probe 9 and reflected on the inner peripheral surface of the valve stem 4 while reflecting the valve stem. The arrival time (echo arrival time) of the ultrasonic wave scanned inside the ultrasonic probe 4 to the ultrasonic probe 9 is read to determine whether the valve stem 4 is abnormal.
〔発明の効果〕 本発明は請求項１に記載したような構成を備えたの
で、弁装置を分解することなく、弁装置の弁箱と弁蓋内
部に位置する弁棒バックシート部の割れ等の異常の有無
の点検を超音波を利用して非接触で能率よく正確に行う
ことができ、これによって弁棒バックシート部の異常の
点検にかかる作業およびび作業時間を低減することがで
きる。この弁棒の異常診断装置を原子力プラントに設置
されている弁装置の弁棒の点検に使用することにより、
弁装置の分解作業が不要となるので、点検時の作業者の
被曝を低減することができるといった効果がある。[Effects of the Invention] Since the present invention has the configuration as described in claim 1, the valve stem backsheet portion located inside the valve box and the valve lid of the valve device can be cracked without disassembling the valve device. Inspection of the presence or absence of abnormalities can be efficiently and accurately performed by using ultrasonic waves without contact, so that the work and time required for inspecting the abnormalities of the valve stem back seat portion can be reduced. By using this valve stem abnormality diagnosis device to inspect the valve stem of a valve device installed in a nuclear power plant,
Since the disassembly work of the valve device is not required, there is an effect that the exposure of the worker at the time of inspection can be reduced.
第１図は本発明に係る弁棒の異常診断装置の一実施例を
示す概略構成図、第２図は第１図のＡ部拡大図、第３図
は同じく第１図のＢ部拡大図、第４図（Ａ）〜（Ｃ）は
超音波による軸力測定における底面エコーの到達状態の
違いをそれぞれ示す図、第５図及び第６図は本発明の弁
棒の異常診断装置の他の実施例を示すもので、第５図は
第１図相当図、第６図は第３図相当図である。 １…弁箱、２…弁蓋、４…弁棒、６…弁体、７…バック
シート部、８…割れ、９…超音波探触子。FIG. 1 is a schematic configuration diagram showing an embodiment of a valve stem abnormality diagnosis apparatus according to the present invention, FIG. 2 is an enlarged view of a portion A of FIG. 1, and FIG. 3 is an enlarged view of a portion B of FIG. 4 (A) to 4 (C) are diagrams showing the difference in the state of arrival of the bottom echo in the measurement of axial force by ultrasonic waves, respectively. FIGS. 5 and 6 are other diagrams of the valve stem abnormality diagnosis apparatus of the present invention. FIG. 5 is a diagram corresponding to FIG. 1, and FIG. 6 is a diagram corresponding to FIG. DESCRIPTION OF SYMBOLS 1 ... valve box, 2 ... valve lid, 4 ... valve stem, 6 ... valve body, 7 ... back seat part, 8 ... crack, 9 ... ultrasonic probe.
Claims (1)
箱と弁蓋の間に昇降自在に配置し、上記弁体の昇降によ
って前記弁箱と弁蓋の内部に位置する弁棒バックシート
部に発生する割れ等の異常を診断する弁棒の異常診断装
置において、弁棒に超音波を内部走査させる超音波探触
子を設置し、この超音波探触子からの超音波が前記弁棒
のバックシート部で反射して到達するまでの超音波の到
達時間を検出して弁棒の異常の有無を診断することを特
徴とする弁棒の異常診断装置。1. A valve body is connected to the tip of a valve stem, and the valve body is disposed between a valve box and a valve cover so as to be able to move up and down. In a valve stem abnormality diagnostic device for diagnosing abnormalities such as cracks occurring in a valve stem back sheet portion, an ultrasonic probe for internally scanning ultrasonic waves is installed on the valve stem, and an ultrasonic probe from the ultrasonic probe is provided. An abnormality diagnosis device for a valve stem, characterized in that it detects the time of arrival of the ultrasonic wave until the ultrasonic wave is reflected by the back sheet portion of the valve stem and arrives, thereby diagnosing the abnormality of the valve stem.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2206748A JP2868861B2 (en) | 1990-08-06 | 1990-08-06 | Valve stem abnormality diagnosis device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2206748A JP2868861B2 (en) | 1990-08-06 | 1990-08-06 | Valve stem abnormality diagnosis device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0493652A JPH0493652A (en) | 1992-03-26 |
| JP2868861B2 true JP2868861B2 (en) | 1999-03-10 |
Family
ID=16528448
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2206748A Expired - Lifetime JP2868861B2 (en) | 1990-08-06 | 1990-08-06 | Valve stem abnormality diagnosis device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2868861B2 (en) |
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|---|---|---|---|---|
| JP5232061B2 (en) * | 2009-03-31 | 2013-07-10 | 株式会社東芝 | Valve stem diagnosis device and method for valve device |
| JP5624515B2 (en) * | 2011-06-01 | 2014-11-12 | 株式会社東芝 | Valve diagnosis device and valve diagnosis method |
| CN108445080A (en) * | 2011-07-21 | 2018-08-24 | 费希尔控制国际公司 | Control valve monitoring system |
| JP6100115B2 (en) * | 2013-07-08 | 2017-03-22 | 株式会社東芝 | Valve stem load measuring device, valve stem load measuring method and valve stem load measuring program |
-
1990
- 1990-08-06 JP JP2206748A patent/JP2868861B2/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20140045540A (en) * | 2011-07-21 | 2014-04-16 | 피셔콘트롤스인터내쇼날엘엘씨 | Control valve monitoring system |
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| US9494560B2 (en) | 2011-07-21 | 2016-11-15 | Fisher Controls International Llc | Control valve monitoring system |
| US10197185B2 (en) | 2011-07-21 | 2019-02-05 | Fisher Controls International Llc | Control valve monitoring system |
| KR101952476B1 (en) * | 2011-07-21 | 2019-02-26 | 피셔콘트롤스인터내쇼날엘엘씨 | Control valve monitoring system |
| US10550959B2 (en) | 2011-07-21 | 2020-02-04 | Fisher Controls International Llc | Control valve monitoring system |
| US20210247268A1 (en) * | 2018-06-20 | 2021-08-12 | Yokogawa Electric Corporation | Valve diagnosis apparatus, valve apparatus, and valve diagnosis method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0493652A (en) | 1992-03-26 |
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