JPH0439621B2 - - Google Patents

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Publication number
JPH0439621B2
JPH0439621B2 JP59143315A JP14331584A JPH0439621B2 JP H0439621 B2 JPH0439621 B2 JP H0439621B2 JP 59143315 A JP59143315 A JP 59143315A JP 14331584 A JP14331584 A JP 14331584A JP H0439621 B2 JPH0439621 B2 JP H0439621B2
Authority
JP
Japan
Prior art keywords
detected
unevenness
probe
eddy current
tissue unevenness
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
Application number
JP59143315A
Other languages
Japanese (ja)
Other versions
JPS6123962A (en
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed filed Critical
Priority to JP14331584A priority Critical patent/JPS6123962A/en
Publication of JPS6123962A publication Critical patent/JPS6123962A/en
Publication of JPH0439621B2 publication Critical patent/JPH0439621B2/ja
Granted legal-status Critical Current

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Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/72Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
    • G01N27/82Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
    • G01N27/90Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents
    • G01N27/904Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents with two or more sensors

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth 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 Magnetic Means (AREA)

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は主として圧延用ロールの表面および表
層部(以下表面部という)に発生した組織むらを
定量的に検出する方法に関するものである。
DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention mainly relates to a method for quantitatively detecting texture unevenness occurring on the surface and surface layer portion (hereinafter referred to as surface portion) of a rolling roll.

〔従来の技術〕[Conventional technology]

従来、表面の組織むらを検出する方法として、
狭い範囲については顕微鏡により観察する方法が
行なわれ、広い範囲については塩酸、硝酸によつ
て表面を腐食し、その腐食模様によつて組織むら
を検出するマクロエツチング法が行なわれてき
た。また、表面をシヨツトブラストしたり、剣バ
イトで加工したりしたときの加工肌の光の反射む
らにより組織むらを検出する方法も実施されてき
た。
Conventionally, as a method for detecting surface tissue unevenness,
For small areas, observation using a microscope has been used, and for large areas, macro-etching has been used, in which the surface is corroded with hydrochloric acid or nitric acid, and tissue unevenness is detected from the corrosion pattern. Additionally, methods have been implemented in which tissue unevenness is detected by the unevenness of light reflection on processed skin when the surface is shot blasted or processed with a sword bite.

いずれの場合も、作業条件、観察条件によつて
検出精度に差が生じる。また、標準試料との比較
観察であるから個人的主観のはいつた定性的判断
であつた。このため、組織むらの分布と程度につ
いてな定量的に把握されていなかつた。
In either case, detection accuracy varies depending on work conditions and observation conditions. Furthermore, since the observation was comparative with a standard sample, it was a qualitative judgment based on personal subjectivity. For this reason, the distribution and degree of tissue unevenness have not been quantitatively understood.

このような従来の検出方法によると、例えば、
極めて軽微な組織むらが存在するが全く問題にな
らないものと判断した圧延用ロールが圧延に供さ
れた結果、軽微で問題にならないと判断された組
織むらが圧延成品に転写され成品等級が下がる結
果となり、多大な損失を招くこともあつた。
According to such conventional detection methods, for example,
A rolling roll with very slight structural unevenness that was determined to be no problem at all was subjected to rolling, and as a result, the structural unevenness that was judged to be slight and non-problematic was transferred to the rolled product, resulting in a lower grade of the product. This sometimes resulted in huge losses.

そこで、上記従来の組織むらの検出方法の問題
点を解消するため、電磁誘導を用いた渦流探傷法
によつて組織むらを定量的に検出することが可能
であれば、その分布、程度から圧延成品への影響
を判断することができて成品等級低下による損失
の防止が可能になるのである。
Therefore, in order to solve the above-mentioned problems with the conventional detection method of texture unevenness, if it is possible to quantitatively detect texture unevenness by eddy current flaw detection using electromagnetic induction, it is possible to By being able to judge the impact on the finished product, it becomes possible to prevent losses due to a decline in the grade of the finished product.

渦流探傷法は微少な表面疵の検出、異材質の判
別および例えば異材質の介在に相当するような極
端で大きな組織変化部の検出などでは可能であり
実用化されている。特に近年は、薄板圧延用ワー
クロールが圧延に供されて表面に発生した疵の検
出用として普及しつつある。
The eddy current flaw detection method is possible and has been put to practical use in detecting minute surface flaws, distinguishing between different materials, and detecting extremely large structural changes corresponding to the presence of different materials. Particularly in recent years, work rolls for rolling thin plates have become popular for use in detecting flaws generated on the surface during rolling.

〔発生が解決しようとする問題点〕[The problem that the outbreak is trying to solve]

しかし、上記従来の渦流探傷法では、例えば圧
延用ロールを遠心鋳造法により製造したときに、
同一材質であるにもかかわらず発生した僅かな鋳
造組織の変化、すなわち極く軽微な組織むらの検
出は不可能である。圧延用ロールに発生する組織
むらは、1φ位の小さなものから100φ以上の大き
なもの、さらには帯状に細長く延びたものなど多
種類があり、これらは従来の渦流探傷法では検出
不可能であつた。
However, in the above conventional eddy current flaw detection method, for example, when a rolling roll is manufactured by centrifugal casting,
It is impossible to detect slight changes in the casting structure, that is, extremely slight unevenness in the structure, even though they are made of the same material. There are many types of structural irregularities that occur on rolling rolls, from as small as 1φ to as large as 100φ or more, and even long and thin strips, which cannot be detected using conventional eddy current testing. .

すなわち、従来の渦流探傷に使用するプローブ
は、第6図に示すように圧延用ロールーの表面と
ほぼ垂直でコイル間隔lを保つて互いに平行なコ
イル10a,10bを有するものである。そし
て、上記組織むらを検出しようとするときは感度
を高める必要があるが、走査中に振動等によりプ
ローブ4aとロール7の表面とに傾きが発生する
と信号中にノイズが相当混入し、組織むらの検出
には到底使用できないのである。
That is, the probe used in the conventional eddy current flaw detection has coils 10a and 10b that are substantially perpendicular to the surface of a rolling roll and parallel to each other with a coil spacing l as shown in FIG. When trying to detect the above-mentioned tissue unevenness, it is necessary to increase the sensitivity, but if the surface of the probe 4a and the roll 7 are tilted due to vibration etc. during scanning, a considerable amount of noise will be mixed into the signal, and the tissue unevenness will be detected. It cannot be used for detection.

本発明は従来の渦流探傷法では検出できなかつ
た上記多種類の組織むらを、定量的にその分布と
程度を同時に検討することができる渦流による検
出方法を提供しようとするものである。
The present invention aims to provide an eddy current detection method that can simultaneously quantitatively examine the distribution and degree of the various types of tissue unevenness that could not be detected using conventional eddy current flaw detection methods.

〔問題点を解決するための手段〕[Means for solving problems]

本発明の渦流による組織むら検出方法は、非磁
性体のコイル芯に中央側から見て同方向に巻回し
た、一対のコイルの各々の巻回軸芯に対する直角
面が、被検出体に向かつて拡開するようにして、
狭い範囲に磁束を集束せしめたプローブを、被検
出体の表面に近接させて加電し、被検出体とプロ
ーブとを相対的に移動させ、被検出体の表面部に
発生する渦電流の変化をとらえることにより、被
検出体の表面部に発生している組織むらを検出す
ることを特徴とするものである。
In the method of detecting tissue unevenness using an eddy current according to the present invention, a pair of coils are wound in the same direction when viewed from the center around a non-magnetic coil core, and the planes perpendicular to the winding axis of each pair of coils face the object to be detected. As it once expanded,
A probe with magnetic flux focused in a narrow range is brought close to the surface of the object to be detected, and the probe is moved relative to the object to be detected, thereby changing the eddy current generated on the surface of the object. It is characterized by detecting tissue unevenness occurring on the surface of the object to be detected by capturing the information.

〔作用〕[Effect]

被検出体とプローブとを相対的に移動させてプ
ローブで被検出体の表面を走査したとき、被検出
体の表面部に組織むらが存在していると、透磁
率、導電率が他の正常な組織の部分に比べて変化
するため、渦電流のブリツジバランスに変動を生
じる。この変動は組織むらの程度によつて大きく
なつたり、小さくなつたりするので、この変動を
信号としてとらえて、例えば、警報を発生させた
りブラウン管に表示したり被検出体表面に場所を
印示したりし、さらにはX−Yプロツターにその
分布を記録すると共に、ペンレコダーにその程度
を記録することにより組織むらを検出するのであ
る。
When the object to be detected and the probe are moved relative to each other and the surface of the object to be detected is scanned by the probe, if there is tissue unevenness on the surface of the object to be detected, the magnetic permeability and conductivity will be different from normal. This causes fluctuations in the bridge balance of eddy currents. This variation becomes larger or smaller depending on the degree of tissue unevenness, so this variation can be captured as a signal, for example, to generate an alarm, display it on a cathode ray tube, or mark the location on the surface of the object to be detected. Furthermore, tissue unevenness is detected by recording its distribution on an X-Y plotter and recording its degree on a pen recorder.

本発明において使用するプローブは、第3図に
示すように被検出体(実施例では圧延用ロール)
7に向かつて距離tだけ拡開するように、第2図
a,bに示すベークライトなどのの非磁性体より
なるコイル芯8に逆V字型、すなわち一対のコイ
ルの各々の巻回軸芯に対する直角面が被検出体に
向かつて拡開し、一対の各々は中央側から見て同
方向に巻回されたコイル10を有している。従つ
て、磁力線9はコイル10が拡開した距離tの狭
い範囲に集中して矢方向に発生する。
The probe used in the present invention is an object to be detected (a rolling roll in the embodiment) as shown in FIG.
The coil core 8 made of a non-magnetic material such as Bakelite shown in FIGS. A perpendicular surface thereof widens toward the object to be detected, and each of the pair has a coil 10 wound in the same direction when viewed from the center side. Therefore, the magnetic lines of force 9 are concentrated in a narrow range of the distance t where the coil 10 is expanded and are generated in the direction of the arrow.

このように狭い範囲に磁束を集束させることに
よつて、プローブを走査させる際振動等によつて
プローブと被検出体とに傾きが発生しても、従来
のプローブに比してその影響が少なく、ノイズの
発生を極く低く抑えることができるのである。従
つて、微小な渦電流のブリツジバランスの変動を
確実にとらえて表示し、従来不可能であつた組織
むらの検出を可能にしたものである。
By focusing the magnetic flux in a narrow range in this way, even if the probe and the object to be detected are tilted due to vibration etc. when scanning the probe, the effect is less than with conventional probes. This makes it possible to suppress noise generation to an extremely low level. Therefore, fluctuations in the bridge balance of minute eddy currents are reliably captured and displayed, making it possible to detect tissue unevenness, which was previously impossible.

また、コイルの拡開距離tが異なる種類のプロ
ーブを2個以上用いた多チヤンネル方式にするこ
とにより、渦電流の変化をとらえやすくして、微
小組織むらから広範囲組織むらに至る各種類組織
むらの同時検出を可能になしうるものである。
In addition, by using a multi-channel system that uses two or more types of probes with different coil expansion distances t, changes in eddy currents can be easily detected, and various types of tissue unevenness, ranging from minute tissue unevenness to wide-scale tissue unevenness, can be detected. It is possible to simultaneously detect the following.

〔実施例〕〔Example〕

第1図は本発明の実施状況を示す説明図であ
る。
FIG. 1 is an explanatory diagram showing the implementation status of the present invention.

第1図において、4,4′は前記逆V字型コイ
ル10を有するプローブで、コイル10の拡開距
離は一方が2mm、他方が5mmと異なつた拡開距離
のものを2個並べ、コイル10の拡開した側を回
転自在に支承されたロール7に対向させ、その先
端をロール7の表面に近接して設置し、ロール7
を回転させながら長手方向に胴長Lの間を移動さ
せて、ロール表面全体の走査ができるようになつ
ている。
In FIG. 1, 4 and 4' are probes having the above-mentioned inverted V-shaped coil 10, and two coils 10 with different expansion distances, one of which is 2 mm and the other of which is 5 mm, are lined up. The enlarged side of the roll 10 faces the rotatably supported roll 7, and the tip thereof is placed close to the surface of the roll 7.
The entire surface of the roll can be scanned by moving it along the length L in the longitudinal direction while rotating the roll.

すなわち、本実施例においてはプローブを4,
4′の2個使用する2チヤンネル方式で、一方の
プローブ(コイルの拡開距離2mm)は微小組織む
ら検出用(CH1)であり、他方のプローブ(コ
イル拡開距離5mm)は広範囲組織むら検出用
(CH2)である。
That is, in this example, there are 4 probes,
4' is a two-channel method using two probes, one probe (coil expansion distance 2 mm) is for detecting minute tissue unevenness (CH1), and the other probe (coil expansion distance 5 mm) is for detecting wide range tissue unevenness. (CH2).

渦流探傷装置本体1から256kHzの高周波数の
励磁電流を一方のプローブ4に、64kHzの低周波
数の励磁電流を他方のプローブ4′に加電して、
回転するロール7の表面部に渦電流を発生させ、
プローブ4,4′をロール7の長手方向に移動さ
せてロール7の全外表面を走査する。
A high frequency excitation current of 256 kHz is applied from the eddy current flaw detection device body 1 to one probe 4, and a low frequency excitation current of 64 kHz is applied to the other probe 4'.
Generating an eddy current on the surface of the rotating roll 7,
The probes 4, 4' are moved in the longitudinal direction of the roll 7 to scan the entire outer surface of the roll 7.

このとき、ロール7の表面部に組織むら15が
存在すると、透磁率、導電率が変化して渦電流の
ブリツジバランスに変動を生じるので、この変動
を信号としてとらえ、組織むら15の分布をロー
ル表面展開図としてX−Yプロツター2により、
第4図に示すようにX−Yプロツター記録紙11
に記録し、その程度をペンレコダー3により第5
図に示すようにペンレコダー記録紙14に記録す
る。なお6は円周位置検出器である。
At this time, if the texture unevenness 15 exists on the surface of the roll 7, the magnetic permeability and electrical conductivity will change and the bridge balance of the eddy current will fluctuate, so this variation is taken as a signal and the distribution of the texture unevenness 15 is determined. As a developed roll surface diagram, use X-Y plotter 2.
As shown in FIG. 4, the X-Y plotter recording paper 11
Record the degree using the pen recorder 3 on the 5th page.
The information is recorded on the pen recorder recording paper 14 as shown in the figure. Note that 6 is a circumferential position detector.

なお、X−Yプロツター2は1円周を記録する
ために、第4図に示すようにNo.1ペン1、No.2ペ
ン13の2ペンを用い、No.1ペン12でX−Yプロツ
ター記録紙11に半周記録したら元の位置に戻
り、戻り間に次のNo.2ペン13で次の半周を記録す
る。No.2ペン13が戻る間にNo.1ペンで記録すると
いう連続記録方式となつている。そして、組織む
らがあると第4図に示すように線が波型に乱れて
記録される。また、第4図中Lはロール7の胴
長、Pはプローブ4,4′の送りのピツチである。
In addition, in order to record one circumference, the X-Y plotter 2 uses two pens, No. 1 pen 1 and No. 2 pen 13, as shown in Fig. 4. After recording half a revolution on the plotter recording paper 11, return to the original position and record the next half revolution with the next No. 2 pen 13 while returning. It is a continuous recording method in which the No. 1 pen records while the No. 2 pen 13 returns. If there is tissue unevenness, the lines will be recorded in a wavy manner as shown in FIG. Further, in FIG. 4, L is the body length of the roll 7, and P is the feeding pitch of the probes 4, 4'.

さらに、ペンレコダー3による記録は、CH1
プローブ、CH2プローブ別にペンレコダー記録
紙14に記録し、振巾の高さで組織むらの程度の
判断ができるようになつている。
Furthermore, recording by pen recorder 3 is CH1
The probe and CH2 probe are recorded separately on a pen recorder recording paper 14, and the degree of tissue unevenness can be judged based on the height of the swing width.

さらに、組織むらの存在を信号としてとらえた
場合は、プローブ4,4′の近傍に併設したマー
カー5からペンキを噴射してロール表面に組織む
らの位置を明示する。
Further, if the presence of tissue unevenness is detected as a signal, paint is sprayed from the marker 5 provided near the probes 4, 4' to clearly indicate the position of the tissue unevenness on the roll surface.

なお、渦流探傷に際しては、ロール表面部の組
織むらが最も検出しやすいような、例えばプロー
ブ(CH1、CH2)の励磁電流、周波数、探傷面
(ロール表面)の周速度、プローブと探傷面との
ギヤツプ等の条件を設定して行なう。
In addition, when performing eddy current flaw detection, the excitation current and frequency of the probes (CH1, CH2), the circumferential speed of the flaw detection surface (roll surface), and the relationship between the probe and the flaw detection surface are selected so that tissue unevenness on the roll surface can be most easily detected. This is done by setting conditions such as gaps.

以上のようにしてロール表面部の渦流探傷を行
なつた結果、コイル拡開距離2mmのプローブでは
スポツト状の小さな組織むらが精度よく検出で
き、コイル拡開距離5mmのプローブでは境界が不
明瞭な模様状の組織むらが精度よく検出できた。
そして、両方のプローブを用いた2チヤンネル方
式の上記実施例では多種類の組織むらを精度よく
定量的に検出することができたのである。
As a result of performing eddy current flaw detection on the roll surface as described above, the probe with a coil expansion distance of 2 mm can accurately detect small spot-like tissue irregularities, while the probe with a coil expansion distance of 5 mm can detect unclear boundaries. Pattern-like tissue unevenness could be detected with high accuracy.
In the above embodiment of the two-channel system using both probes, it was possible to quantitatively detect various types of tissue unevenness with high accuracy.

〔発明の効果〕〔Effect of the invention〕

上述のように本発明は、被検出体に向かつてい
わゆる逆V字型に拡開したコイルを有するプロー
ブを用い、狭い範囲に磁束を集束させて被検出体
の表面部に渦電流を発生させ、その変化をとらえ
て組織むらを検出するようにしたので、コイルの
拡開距離を適宜定めることにより、スポツト状の
小さな組織むらから模様状の大きな組織むらまで
精度よく検出することができ、またコイルの拡開
距離の異なるプローブを2個以上用いることによ
り、大きさや形状の異なる多種類の組織むらを精
度よく検出でき、さらに被検出体の表面を平面に
展開して表示することにより組織むらを定量的に
把握することができて、組織むらに起因する損失
を未然に防止することができる等工業上多大の効
果を有するものである。
As described above, the present invention uses a probe having a coil that expands in a so-called inverted V shape toward the object to be detected, and focuses magnetic flux in a narrow range to generate eddy currents on the surface of the object to be detected. Since tissue unevenness is detected by capturing these changes, by setting the expansion distance of the coil appropriately, it is possible to accurately detect from small spot-like tissue unevenness to large pattern-like tissue unevenness. By using two or more probes with different coil expansion distances, it is possible to accurately detect many types of tissue irregularities with different sizes and shapes. Furthermore, by displaying the surface of the object to be detected as a flat surface, tissue irregularities can be detected. It has a great industrial effect, such as being able to quantitatively understand the amount of damage caused by tissue unevenness and preventing losses caused by unevenness in the structure.

なお、前記は主として圧延用ロールについて本
発明を説明したが、本発明は圧延用ロールに限ら
ず、渦電流が発生するとともにプローブの走査が
可能な物品であれば何にでも適用できて効果を奏
するものである。
Although the present invention has been described above mainly with respect to rolling rolls, the present invention is not limited to rolling rolls, but can be applied to any article that generates eddy currents and can be scanned with a probe, and can be effectively applied. It is something to play.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明の一実施例を示す説明図、第2
図a,bはプローブのコイル芯の正面図および底
面図、第3図は逆V字型コイルを有するプローブ
の正面図、第4図はX−Yプロツター記録紙の平
面図、第5図はペンレコダー記録紙の平面図、第
6図は従来のプローブの説明図である。 1:渦流探傷装置本体、2:X−Yプロツタ
ー、3:ペンレコダー、4,4′:プローブ、
7:ロール、8:コイル芯、9:磁力線、10:
コイル、11:X−Yプロツター記録紙、14:
ペンレコダー記録紙。
FIG. 1 is an explanatory diagram showing one embodiment of the present invention, and FIG.
Figures a and b are front and bottom views of the coil core of the probe, Figure 3 is a front view of the probe with an inverted V-shaped coil, Figure 4 is a plan view of the X-Y plotter recording paper, Figure 5 is FIG. 6, which is a plan view of the pen recorder recording paper, is an explanatory diagram of a conventional probe. 1: Eddy current flaw detection device body, 2: X-Y plotter, 3: Pen recorder, 4, 4': Probe,
7: Roll, 8: Coil core, 9: Lines of magnetic force, 10:
Coil, 11: X-Y plotter recording paper, 14:
Pen recorder recording paper.

Claims (1)

【特許請求の範囲】 1 非磁性体のコイル芯に中央側から見て同方向
に巻回した、一対のコイルの各々の巻回軸芯に対
する直角面が、被検出体に向かつて拡開するよう
にして、狭い範囲に磁束を集束せしめたプローブ
を、被検出体の表面に近接させて加電し、被検出
体とプローブとを相対的に移動させ、被検出体の
表面部に発生する渦電流の変化をとらえることに
より、被検出体の表面部に発生している組織むら
を検出することを特徴とする渦流による組織むら
検出方法。 2 コイルの拡開距離が異なる種類のプローブを
2個以上用いることを特徴とする特許請求の範囲
第1項記載の渦流による組織むら検出方法。 3 プローブの走査と連動させることにより被検
出体の表面を平面に展開し、前記被検出体の表面
部に発生した組織むらの分布および程度を前記展
開した平面中に表示することを特徴とする特許請
求の範囲第1項または第2項記載の渦流による組
織むら検出方法。 4 被検出体が圧延用ロールであることを特徴と
する特許請求の範囲第1項ないし第3項のうちの
いずれかに記載の渦流による組織むら検出方法。
[Scope of Claims] 1. A pair of coils wound in the same direction when viewed from the center around a non-magnetic coil core. The planes perpendicular to the winding axis of each pair of coils widen toward the detected object. In this way, a probe with magnetic flux focused in a narrow range is brought close to the surface of the object to be detected and electrified, and the object to be detected and the probe are moved relative to each other, causing magnetic flux to be generated on the surface of the object to be detected. A method for detecting tissue unevenness using eddy currents, which is characterized by detecting tissue unevenness occurring on the surface of an object to be detected by capturing changes in eddy currents. 2. The method for detecting tissue unevenness using an eddy current according to claim 1, characterized in that two or more probes of different types of coil expansion distances are used. 3. The surface of the object to be detected is developed into a flat plane in conjunction with the scanning of the probe, and the distribution and degree of tissue unevenness occurring on the surface of the object to be detected are displayed on the developed plane. A method for detecting tissue unevenness using an eddy current according to claim 1 or 2. 4. A method for detecting tissue unevenness using an eddy current according to any one of claims 1 to 3, wherein the object to be detected is a rolling roll.
JP14331584A 1984-07-12 1984-07-12 Detecting method of structure irregularity by eddy current Granted JPS6123962A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14331584A JPS6123962A (en) 1984-07-12 1984-07-12 Detecting method of structure irregularity by eddy current

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14331584A JPS6123962A (en) 1984-07-12 1984-07-12 Detecting method of structure irregularity by eddy current

Publications (2)

Publication Number Publication Date
JPS6123962A JPS6123962A (en) 1986-02-01
JPH0439621B2 true JPH0439621B2 (en) 1992-06-30

Family

ID=15335916

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14331584A Granted JPS6123962A (en) 1984-07-12 1984-07-12 Detecting method of structure irregularity by eddy current

Country Status (1)

Country Link
JP (1) JPS6123962A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3551739B2 (en) * 1997-12-22 2004-08-11 住友金属工業株式会社 Crack inspection method for rolling rolls

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS528886A (en) * 1975-07-09 1977-01-24 Kubota Ltd Cast iron pipe structure judging unit
JPS5730971A (en) * 1980-07-31 1982-02-19 Ponii Sangyo Kk Metal detector

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS528886A (en) * 1975-07-09 1977-01-24 Kubota Ltd Cast iron pipe structure judging unit
JPS5730971A (en) * 1980-07-31 1982-02-19 Ponii Sangyo Kk Metal detector

Also Published As

Publication number Publication date
JPS6123962A (en) 1986-02-01

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