JP3189136B2 - Method and apparatus for measuring material deterioration - Google Patents
Method and apparatus for measuring material deteriorationInfo
- Publication number
- JP3189136B2 JP3189136B2 JP02716393A JP2716393A JP3189136B2 JP 3189136 B2 JP3189136 B2 JP 3189136B2 JP 02716393 A JP02716393 A JP 02716393A JP 2716393 A JP2716393 A JP 2716393A JP 3189136 B2 JP3189136 B2 JP 3189136B2
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- detection
- crack
- conductor
- deterioration
- 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
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- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は材料の劣化計測方法及び
装置、特に金属、セラミックス等の導電性材料の材質変
化及びき裂の有無及び程度を検知する方法及び装置に関
するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring deterioration of a material, and more particularly to a method and an apparatus for detecting a change in the material of a conductive material such as metal or ceramics and the presence or absence and the degree of a crack.
【0002】[0002]
【従来の技術】例えば、火力プラントのボイラーヘッダ
ー、タービンロータ及びタービンケーシング等において
は疲労によるき裂が発生した場合、重大な事故につなが
ることになる。このような金属等の表面あるいはその内
部にき裂がある場合、その金属材料のき裂を挟んだ2点
間に交流または直流の電流を流し、き裂を挟む部分の電
圧を測定することでき裂の有無や、き裂の深さを知るよ
うにしたものは既知である。2. Description of the Related Art For example, if a crack occurs due to fatigue in a boiler header, a turbine rotor, a turbine casing, or the like of a thermal power plant, a serious accident may occur. When there is a crack on the surface of such a metal or the like, an AC or DC current can flow between the two points sandwiching the crack in the metal material, and the voltage across the crack can be measured. It is known to know the presence or absence of a crack and the depth of a crack.
【0003】図4は従来の材料の劣化計測方法の説明図
であって、1は導電性材料、2はこれに生じたき裂、3
は例えば数ボルトの交流または直流電源、4は、例えば
5〜10mm互いに離間する位置で上記材料1に接触せ
しめた2組の検知電極を示す。この方法では、材料1
の、例えば数cm〜数10cm離間した2点間に電圧印
加電極(図示せず)を介して上記電源3の電圧を印加し
て、例えば数〜数10アンペアの電流を上記材料1に流
し、上記検知電極4,4間の電圧を電圧計5によって検
出し一方の組の検知電極4によって検出した電圧の値
が、他の組の検知電極4によって検出した電圧の値より
例えば数〜数十マイクロボルト大きいとき、上記一方の
組の検知電極4間にき裂2が存在するものと判定し、ま
た両者の電圧の比からき裂2の深さを判定している。FIG. 4 is an explanatory view of a conventional method for measuring the deterioration of a material, wherein 1 is a conductive material, 2 is a crack generated therein,
Indicates an AC or DC power supply of several volts, for example, and 4 indicates two sets of detection electrodes which are brought into contact with the material 1 at positions separated from each other by, for example, 5 to 10 mm. In this method, material 1
For example, a voltage of the power supply 3 is applied between two points separated by, for example, several cm to several tens of cm via a voltage application electrode (not shown), and a current of, for example, several to several tens of amperes is caused to flow through the material 1. The voltage between the detection electrodes 4 and 4 is detected by a voltmeter 5 and the value of the voltage detected by one set of the detection electrodes 4 is, for example, several to several tens of times smaller than the value of the voltage detected by the other set of the detection electrodes 4. When the voltage is larger by microvolts, it is determined that the crack 2 exists between the one set of the detection electrodes 4, and the depth of the crack 2 is determined from the ratio of the two voltages.
【0004】図5は従来の他の劣化計測方法の説明図で
あって、この方法においては、電流を直接材料1に流す
代わりに直径が例えば1cmのコイル6に交流電流を流
し、このコイル6によって発生した磁界により材料1内
に磁気誘導渦電流を発生せしめ、き裂があった場合にコ
イル6に生ずる電圧の変化と、電流と電圧の位相が変化
することからき裂の有無を検知している。FIG. 5 is an explanatory view of another conventional deterioration measuring method. In this method, instead of flowing an electric current directly to the material 1, an alternating current is applied to a coil 6 having a diameter of 1 cm, for example. A magnetically induced eddy current is generated in the material 1 by the magnetic field generated by the magnetic field, and the presence or absence of a crack is detected based on the change in the voltage generated in the coil 6 and the phase of the current and the voltage when the crack occurs. I have.
【0005】[0005]
【発明が解決しようとする課題】然しながら上記図3に
示す方法では、電圧印加電極によって材料1の2点間に
電圧を印加したとき、き裂2を通してのみならずその周
辺にも一様に電流が流れることになるためき裂2の両端
に生ずる電圧が少なくなり、この電圧を大きくするため
には必要以上に大きい電圧を材料1に印加しなければな
らず、また、そのため大きな電流が流れて材料1に熱を
発生する等種々の不都合があった。However, in the method shown in FIG. 3, when a voltage is applied between two points of the material 1 by the voltage applying electrode, the current is uniformly applied not only through the crack 2 but also around the crack 2. Flows, the voltage generated at both ends of the crack 2 decreases, and in order to increase this voltage, an unnecessarily large voltage must be applied to the material 1, and therefore, a large current flows. The material 1 has various disadvantages such as generating heat.
【0006】また、検知すべき区域の変更には、その都
度材料1に対する電圧印加電極の脱着が必要となり、能
率が悪い欠点があった。Further, every time the area to be detected is changed, it is necessary to attach and detach the voltage application electrode to / from the material 1, which has a disadvantage that efficiency is poor.
【0007】また、図5に示す方法では、材料に対する
電圧印加用電極や検知電極4が不要であるという利点は
あるが、1回の測定で検知できる範囲が小さく、き裂2
が材料1の表面に現れていない場合にはき裂の発生して
いる個所の検知に時間がかかると共に、材料1の内部に
延びているき裂の状態を測定することは不可能であっ
た。The method shown in FIG. 5 has the advantage that the voltage application electrode and the detection electrode 4 for the material are not required, but the range that can be detected by one measurement is small, and the crack 2
When the crack did not appear on the surface of the material 1, it took a long time to detect the place where the crack had occurred, and it was impossible to measure the state of the crack extending inside the material 1. .
【0008】本発明は上記の欠点を除くようにしたもの
である。The present invention has been made to eliminate the above disadvantages.
【0009】[0009]
【課題を解決するための手段】本発明の材料の劣化計測
方法は、検知導体を被測定導電性材料に沿って線状に配
置し、この検知導体に交流電流を流し、上記検知導体に
沿った上記材料の複数点間の電圧を検出し、この検出し
た電圧から上記材料の劣化を判断することを特徴とす
る。According to the method for measuring deterioration of a material according to the present invention, a detection conductor is linearly arranged along a conductive material to be measured, an alternating current is passed through the detection conductor, and the detection conductor extends along the detection conductor. Detecting a voltage between a plurality of points of the material, and judging deterioration of the material from the detected voltage.
【0010】上記電流は、可変周波数交流電源から供給
し、その周波数を任意に変えて上記電圧を検出するよう
にする。The current is supplied from a variable frequency AC power supply, and the frequency is arbitrarily changed to detect the voltage.
【0011】本発明の材料の劣化計測装置は、ボデー
と、このボデーの底面に配置せしめた検知導体と、上記
検知導体に沿ったライン上で上記底面に露出せしめた2
個以上の互いに離間した検知電極と、この検知電極間の
電圧を検出する手段とより成り、上記検知導体が被測定
導電性材料上に沿って配置され、これに交流電流が流さ
れることを特徴とする。According to the apparatus for measuring deterioration of a material of the present invention, a body, a detection conductor arranged on the bottom surface of the body, and a detection conductor exposed on the bottom surface along a line along the detection conductor are provided.
A plurality of sensing electrodes spaced apart from each other, and means for detecting a voltage between the sensing electrodes, wherein the sensing conductor is arranged along the conductive material to be measured, and an alternating current is passed through the sensing conductor. And
【0012】上記検出電極は、上記ボデーの底面外に突
出自在である。[0012] The detection electrode can protrude outside the bottom surface of the body.
【0013】上記ボデーの底面は、フレキシブルで任意
の曲面に変形可能である。The bottom surface of the body is flexible and can be deformed into an arbitrary curved surface.
【0014】[0014]
【実施例】以下図面によっ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.
【0015】本発明の材料の劣化計測方法においては、
図1に示すように長さが例えば10〜20cmのエナメ
ル線等の絶縁検知導体7をき裂を検知すべき導電性材料
1の表面に沿って直線状に配置し、この検知導体7に電
源3から例えば数アンペア程度の交流電流を流し、この
結果材料1内に上記検知導体7に沿って磁気誘導電流が
発生されるようにし、上記検知導体7に沿った上記材料
1上の2点間の電圧を上記材料1に接触している検知電
極4,4によって検出せしめ、次に、上記検知導体7及
び検知電極4,4を任意の方向に移動したとき、上記検
知電極4,4間の電圧が増加すれば、これによってこの
検知電極4,4間にき裂2が存在することを検知する。In the method for measuring deterioration of a material according to the present invention,
As shown in FIG. 1, an insulation detecting conductor 7 such as an enameled wire having a length of, for example, 10 to 20 cm is linearly arranged along the surface of the conductive material 1 where a crack is to be detected. 3, an alternating current of, for example, about several amperes is caused to flow, so that a magnetically induced current is generated in the material 1 along the detection conductor 7, and between two points on the material 1 along the detection conductor 7. Is detected by the detection electrodes 4 and 4 that are in contact with the material 1. Then, when the detection conductor 7 and the detection electrodes 4 and 4 are moved in an arbitrary direction, the voltage between the detection electrodes 4 and 4 is detected. If the voltage increases, it detects that the crack 2 exists between the detection electrodes 4 and 4.
【0016】また、このき裂2の部分における電圧を、
上記電線3の周波数を例えば0.3K〜100KHzに
変化せしめて測定し、この測定結果により上記き裂2の
材料1内における深さ方向の形態を判定する。The voltage at the crack 2 is
The frequency of the electric wire 3 is changed, for example, from 0.3 K to 100 KHz for measurement, and the form of the crack 2 in the material 1 in the depth direction is determined based on the measurement result.
【0017】本発明の材料の劣化計測方法は上記のとお
りであるから、検知導体7及び検知電極4,4を材料1
上で移動するのみで容易に検知区域の変更を行うことが
でき、また、材料1には上記検知導体7に沿った部分に
のみ磁気誘導電流が集中的に流れるため、き裂2が発生
している部分では十分に大きな電圧を得ることができ、
感度が大きくなる。Since the method for measuring the deterioration of the material of the present invention is as described above, the detection conductor 7 and the detection electrodes 4 and 4 are made of the material 1
The detection area can be easily changed simply by moving on the upper side. Further, since the magnetically induced current flows intensively only in the portion along the detection conductor 7 in the material 1, a crack 2 is generated. Where you can get a sufficiently large voltage,
Sensitivity increases.
【0018】また、電源の周波数を変えて、例えば周波
数を大きくすればスキン効果によって誘導電流を材料の
表面に沿ってのみ流して表面のみのき裂を検知すること
ができ、逆に周波数を下げて測定を行えば材料の中心部
のき裂に関する情報を検知するようにでき、結果として
き裂の有無のみならず、そのき裂が材料内でどのように
延びているかをも検知できるようになる。If the frequency of the power supply is changed, for example, if the frequency is increased, the induced current can be caused to flow only along the surface of the material by the skin effect to detect cracks only on the surface. Measurement can detect information about cracks in the center of the material, and consequently not only the presence or absence of a crack, but also how the crack extends in the material. Become.
【0019】なお、以上は材料1のき裂2を検知する場
合を説明したが、き裂2の有無にかかわらず上記2個の
検知電極4,4間の電圧は材料1の材質によって異なる
ことから、あらかじめ既知の材質の材料につきその電圧
を測定しておけば、これを参照して未知の材料の材質あ
るいは既知の材料の経年的変化をも検知することができ
る。In the above description, the case where the crack 2 of the material 1 is detected has been described. However, the voltage between the two detection electrodes 4 and 4 differs depending on the material of the material 1 regardless of the presence or absence of the crack 2. Therefore, if the voltage of a known material is measured in advance, it is possible to detect a material of an unknown material or a secular change of the known material with reference to the voltage.
【0020】図2は本発明の材料の劣化計測装置を示
し、本発明においては例えばアルミニウムにミューメタ
ルを被覆せしめた、例えば筒状体のボデー8にその底面
9から垂直方向上方に延びる2個の垂直孔10を設け、
この各垂直孔10内に圧縮スプリング11と検知電極4
をこの順序で挿入し、この検知電極4,4の先端を上記
ボデーの底面9外に突出せしめ、この検知電極4,4の
先端をき裂を検知すべき材料1の面に押圧したとき、こ
の面によって押され、圧縮スプリング11に抗して上記
垂直孔10内に押し込まれ、その先端がボデー8の底面
9に一致され得るようにする。FIG. 2 shows a device for measuring the deterioration of a material according to the present invention. The vertical hole 10 of
The compression spring 11 and the detection electrode 4
Are inserted in this order, and the tips of the detection electrodes 4 and 4 are made to protrude out of the bottom surface 9 of the body. When the tips of the detection electrodes 4 and 4 are pressed against the surface of the material 1 where the crack is to be detected, It is pushed by this surface and pushed into the vertical hole 10 against the compression spring 11 so that its tip can coincide with the bottom surface 9 of the body 8.
【0021】また、上記ボデー8の底面9には上記2個
の検知電極4,4を結ぶライン上で上記検知導体7を絶
縁状態で埋め込み、その両端に可変周波数電源3を接続
し、上記2個の検知電極4,4間には電圧計5を接続せ
しめる。なお、上記検知導体7は上記検知電極4,4と
交叉する部分では検知電極4の外周に沿って迂回せしめ
る。On the bottom surface 9 of the body 8, the detection conductor 7 is buried in an insulated state on a line connecting the two detection electrodes 4 and 4, and the variable frequency power supply 3 is connected to both ends thereof. A voltmeter 5 is connected between the detection electrodes 4 and 4. Note that the detection conductor 7 is detoured along the outer periphery of the detection electrode 4 at a portion where the detection conductor 7 intersects with the detection electrodes 4 and 4.
【0022】また、電波妨害等を防ぐため必要に応じて
上記ボデー8の外周面に金属の網等のシールドをかぶせ
るのが好ましい。Further, it is preferable to cover the outer peripheral surface of the body 8 with a shield such as a metal net, if necessary, in order to prevent radio wave interference or the like.
【0023】本発明の材料の劣化計測装置においてはボ
デー8の底面9部分をゴム等のフレキシブルな材料とし
ておけば、上記検知導体7を測定すべき材料の面が曲面
であってもこれに沿って配置することができるようにな
り、正確な検知が可能となる。In the device for measuring deterioration of a material according to the present invention, if the bottom surface 9 of the body 8 is made of a flexible material such as rubber, even if the surface of the material on which the detection conductor 7 is to be measured is a curved surface, And accurate detection is possible.
【0024】また、本発明の材料の劣化計測方法及び装
置は、強磁性体であるフェライトからアルミニウム、オ
ーステナイト鋼、チタニウム等非磁性の金属や、合金、
電導度の低いセラミックス等の材料等に幅広く適用する
ことができる。Further, the method and apparatus for measuring deterioration of a material according to the present invention can be applied to a ferromagnetic material such as ferrite, non-magnetic metal such as aluminum, austenitic steel, and titanium;
It can be widely applied to materials such as ceramics having low conductivity.
【0025】更に、上記検知導体7として導体箔を用
い、この箔に孔をあけ、この孔を介して上記検知電極
4,4を材料1に接触せしめても良い。Further, a conductor foil may be used as the detection conductor 7, a hole may be formed in the foil, and the detection electrodes 4 and 4 may contact the material 1 through the hole.
【0026】なお、本発明の他の実施例においては図3
に示すように検知電極4,4を2組、上記検知導体7に
沿って配置する。In another embodiment of the present invention, FIG.
2, two sets of detection electrodes 4 and 4 are arranged along the detection conductor 7.
【0027】このようにすれば従来と同様2組の検知電
極4,4の検知電圧の比によってき裂の深さを直ちに計
測することができる。In this way, the depth of the crack can be immediately measured by the ratio of the detection voltages of the two sets of detection electrodes 4 and 4 as in the prior art.
【0028】[0028]
【発明の効果】上記のように本発明によれば、従来の場
合に比べ略数10倍の感度で材料のき裂の有無や、材質
の劣化及び経年変化等を極めて容易に検知できるように
なる大きな利益がある。As described above, according to the present invention, the presence / absence of a crack in a material, the deterioration of the material and the secular change, etc. can be detected very easily with sensitivity several tens of times as compared with the conventional case. There are great benefits.
【図1】本発明の材料の劣化計測方法の説明図である。FIG. 1 is an explanatory view of a method for measuring deterioration of a material according to the present invention.
【図2】本発明の材料の劣化計測装置の説明図である。FIG. 2 is an explanatory diagram of a material deterioration measuring device of the present invention.
【図3】本発明の他の実施例における劣化計測装置の説
明図である。FIG. 3 is an explanatory diagram of a deterioration measuring device according to another embodiment of the present invention.
【図4】従来の材料の劣化計測方法の説明図である。FIG. 4 is an explanatory view of a conventional method for measuring deterioration of a material.
【図5】従来の材料の劣化計測方法の説明図である。FIG. 5 is an explanatory view of a conventional method for measuring deterioration of a material.
1 導電性材料 2 き裂 3 交流または直流電源 4 検知電極 5 電圧計 6 コイル 7 検知導体 8 ボデー 9 底面 10 垂直孔 11 圧縮スプリング DESCRIPTION OF SYMBOLS 1 Conductive material 2 Crack 3 AC or DC power supply 4 Detecting electrode 5 Voltmeter 6 Coil 7 Detecting conductor 8 Body 9 Bottom 10 Vertical hole 11 Compression spring
Claims (6)
状に配置し、 この検知導体に交流電流を流し、 上記検知導体に沿った上記材料の複数点間の電圧を検出
し、 この検出した電圧から上記材料の劣化を判断することを
特徴とする材料の劣化計測方法。1. A detection conductor is linearly arranged along a conductive material to be measured, an alternating current is passed through the detection conductor, and a voltage between a plurality of points of the material along the detection conductor is detected. A method for measuring deterioration of a material, comprising determining deterioration of the material from the detected voltage.
し、その周波数を任意に変えて上記電圧を検出する請求
項1記載の材料の劣化計測方法。2. The method according to claim 1, wherein the current is supplied from a variable frequency AC power supply, and the frequency is arbitrarily changed to detect the voltage.
めた検知導体と、上記検知導体に沿ったライン上で上記
底面に露出せしめた2個以上の互いに離間した検知電極
と、この検知電極間の電圧を検出する手段とより成り、
上記検知導体が被測定導電性材料上に沿って配置され、
これに交流電流が流されることを特徴とする材料の劣化
計測装置。3. A body, a sensing conductor disposed on the bottom surface of the body, two or more spaced sensing electrodes exposed on the bottom surface along a line along the sensing conductor, and a gap between the sensing electrodes. Means for detecting the voltage of
The sensing conductor is arranged along the conductive material to be measured,
An apparatus for measuring deterioration of a material, characterized in that an alternating current is applied to the material.
出自在である請求項3記載の材料の劣化計測装置。4. The apparatus for measuring deterioration of a material according to claim 3, wherein said detection electrode is protrudable outside the bottom surface of said body.
の曲面に変形可能である請求項3または4記載の材料の
劣化計測装置。5. The apparatus according to claim 3, wherein the bottom surface of the body is flexible and deformable into an arbitrary curved surface.
する請求項3,4または5記載の材料の劣化計測装置。6. The apparatus according to claim 3, wherein said current is supplied from a variable frequency AC power supply.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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JP02716393A JP3189136B2 (en) | 1993-01-25 | 1993-01-25 | Method and apparatus for measuring material deterioration |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP02716393A JP3189136B2 (en) | 1993-01-25 | 1993-01-25 | Method and apparatus for measuring material deterioration |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH06222021A JPH06222021A (en) | 1994-08-12 |
JP3189136B2 true JP3189136B2 (en) | 2001-07-16 |
Family
ID=12213395
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JP02716393A Expired - Lifetime JP3189136B2 (en) | 1993-01-25 | 1993-01-25 | Method and apparatus for measuring material deterioration |
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JP (1) | JP3189136B2 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2857988B2 (en) * | 1995-06-07 | 1999-02-17 | 哲雄 庄子 | Non-destructive inspection method and apparatus for conductive spiral specimen |
JP2010281657A (en) * | 2009-06-04 | 2010-12-16 | Ntn Corp | Hardening quality inspection device and hardening quality inspection method |
JP5555506B2 (en) * | 2010-02-19 | 2014-07-23 | 矢崎総業株式会社 | Bonding determination device, electromagnetic pressure welding device, and bonding determination method |
CN114088771A (en) * | 2021-11-09 | 2022-02-25 | 衡阳镭目科技有限责任公司 | Method and device for detecting quality of tab |
-
1993
- 1993-01-25 JP JP02716393A patent/JP3189136B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
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JPH06222021A (en) | 1994-08-12 |
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