JPH08248004A - Fatigue measuring device - Google Patents
Fatigue measuring deviceInfo
- Publication number
- JPH08248004A JPH08248004A JP7990095A JP7990095A JPH08248004A JP H08248004 A JPH08248004 A JP H08248004A JP 7990095 A JP7990095 A JP 7990095A JP 7990095 A JP7990095 A JP 7990095A JP H08248004 A JPH08248004 A JP H08248004A
- Authority
- JP
- Japan
- Prior art keywords
- fatigue
- phase
- exciting
- stainless steel
- dut
- 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.)
- Granted
Links
- 238000001514 detection method Methods 0.000 claims abstract description 41
- 230000005291 magnetic effect Effects 0.000 claims abstract description 18
- 229910000963 austenitic stainless steel Inorganic materials 0.000 claims abstract description 14
- 230000005294 ferromagnetic effect Effects 0.000 claims abstract description 13
- 230000035699 permeability Effects 0.000 claims abstract description 10
- 238000012545 processing Methods 0.000 claims description 10
- 238000007689 inspection Methods 0.000 abstract description 13
- 101100444142 Neurospora crassa (strain ATCC 24698 / 74-OR23-1A / CBS 708.71 / DSM 1257 / FGSC 987) dut-1 gene Proteins 0.000 abstract description 11
- 229910001566 austenite Inorganic materials 0.000 abstract description 5
- 229910000734 martensite Inorganic materials 0.000 abstract description 5
- 230000009466 transformation Effects 0.000 abstract description 4
- 230000004907 flux Effects 0.000 abstract description 3
- 238000005336 cracking Methods 0.000 abstract 1
- 239000000284 extract Substances 0.000 abstract 1
- 238000000034 method Methods 0.000 description 9
- 239000002436 steel type Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000005284 excitation Effects 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 230000010363 phase shift Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000013256 coordination polymer Substances 0.000 description 1
- 238000009661 fatigue test Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
(57)【要約】
【目的】 オーステナイト系ステンレス鋼製の部品につ
いて、疲労により亀裂が発生する前に、その疲労度を測
定する。
【構成】 励磁回路部４から励磁コイル２２に交流の励
磁電流を供給すると、強磁性体棒２１の両端から交番磁
束が放出される。これによりオーステナイト系ステンレ
ス鋼製の被検査物１の表面に渦電流が生成され、検出コ
イル２３、２４の両端には渦電流により起電力が生成さ
れる。位相検波回路３２は、励磁電流の位相に基づいて
検出コイル２３、２４の出力の位相解析を行なうことに
より、被検査物１の透磁率に応じた電気信号を取り出
す。被検査物１に多数回の繰り返し応力が加わり、疲労
が進むと、被検査物１のオーステナイト相が加工変態に
よりマルテンサイト相に変化する。これにより被検査物
１の透磁率が変化し、検出コイル２３、２４の出力の位
相状態が変化する。疲労度算出部５は、この位相状態の
変化に基づいて被検査物１の疲労度を算出する。
(57) [Summary] [Purpose] To measure the degree of fatigue of austenitic stainless steel parts before cracking occurs due to fatigue. [Structure] When an alternating exciting current is supplied from the exciting circuit unit 4 to the exciting coil 22, alternating magnetic flux is emitted from both ends of the ferromagnetic rod 21. As a result, an eddy current is generated on the surface of the inspection object 1 made of austenitic stainless steel, and an electromotive force is generated by the eddy current at both ends of the detection coils 23 and 24. The phase detection circuit 32 extracts the electric signal corresponding to the magnetic permeability of the DUT 1 by performing a phase analysis of the outputs of the detection coils 23 and 24 based on the phase of the exciting current. When stress is repeatedly applied to the inspection object 1 many times and fatigue progresses, the austenite phase of the inspection object 1 changes to a martensite phase due to work transformation. As a result, the magnetic permeability of the DUT 1 changes, and the phase states of the outputs of the detection coils 23 and 24 change. The fatigue level calculator 5 calculates the fatigue level of the DUT 1 based on the change in the phase state.
Description
【０００１】[0001]
【産業上の利用分野】本発明は、オーステナイト系ステ
ンレス鋼製の部品が疲労により亀裂を生じる前にその疲
労度を測定する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 device for measuring the degree of fatigue of an austenitic stainless steel component before it is cracked by fatigue.
【０００２】[0002]
【従来の技術】従来、金属疲労を検出する方法として最
も一般的に行なわれているのは、金属内部に超音波を投
入し、その反射波を検出する方法（超音波検出法）であ
る。これは、検出部の近傍に亀裂が存在する場合、その
亀裂の表面により超音波が反射されるため亀裂の検出が
可能となるものであるが、このような検出原理のため、
亀裂が相当程度大きくないと検出ができないという欠点
がある。また、応力集中部等の亀裂の発生が予想される
箇所に一定の直流又は交流電流を流しておき、その両端
の電圧の変化により亀裂の発生を検出する方法（電位差
法）もある。この方法によると、超音波検出法よりは微
小な亀裂を検出することが可能である。さらに、励磁コ
イルにより交番磁界を印加しておき、フラックスゲート
磁束計で磁界の微小変化を検出することにより亀裂を検
出する方法（フラックスゲート磁束計法。特開平６−３
０８０９２号公報）も考案されている。2. Description of the Related Art Conventionally, the most commonly used method for detecting metal fatigue is a method (ultrasonic wave detection method) of injecting ultrasonic waves into the metal and detecting the reflected waves. This is, if there is a crack in the vicinity of the detection unit, because it is possible to detect the crack because the ultrasonic waves are reflected by the surface of the crack, because of such a detection principle,
It has the disadvantage that it cannot be detected unless the crack is large enough. There is also a method (potential difference method) in which a constant direct current or an alternating current is passed through a location where cracks are expected to occur, such as a stress concentration portion, and the occurrence of cracks is detected by a change in the voltage across the portions. According to this method, it is possible to detect a minute crack as compared with the ultrasonic detection method. Further, a method of detecting cracks by applying an alternating magnetic field by an exciting coil and detecting a minute change of the magnetic field with a fluxgate magnetometer (fluxgate magnetometer method.
No. 08092) has also been devised.
【０００３】[0003]
【発明が解決しようとする課題】以上説明した従来の疲
労検出装置はいずれも、亀裂が発生した後にそれを検出
するものであった。このため、疲労が予想され、しかも
疲労による破壊が極めて重大な問題となる部品では、亀
裂が検出可能な程度にまで大きくなっても部品の破壊が
発生しないように、非常に大きな安全率を見込む必要が
あった。また、金属疲労では一般に亀裂が発生するまで
は非常に長い時間又は繰り返し数が必要であるが、一旦
亀裂が発生すると、その後の亀裂の成長は非常に速いた
め、検査間隔を十分短くとる必要があった。さらに、破
壊よりもむしろ内部のガスや液体等の漏れが問題となる
場合には、亀裂の存在自体が許されない場合もあり得
る。なお、フラックスゲート磁束計法については、フラ
ックスゲート磁束計が外部磁界に対しても極めて敏感で
あるため、不要な雑音磁界によって検出精度が悪化する
という問題もある。All of the conventional fatigue detecting devices described above detect cracks after they occur. For this reason, for parts where fatigue is expected and failure due to fatigue is a very serious problem, a very large safety factor is expected so that the part does not break even if the crack becomes large enough to be detected. There was a need. Further, in metal fatigue, it generally requires a very long time or the number of repetitions until a crack occurs, but once a crack occurs, the growth of the crack thereafter is very fast, and therefore it is necessary to take a sufficiently short inspection interval. there were. Further, when the leakage of gas, liquid, or the like inside rather than destruction is a problem, the existence of the crack itself may not be allowed. Note that the fluxgate magnetometer method is also very sensitive to an external magnetic field, so that there is a problem that the detection accuracy is deteriorated by an unnecessary noise magnetic field.
【０００４】本発明はこのような課題を解決するために
成されたものであり、オーステナイト系ステンレス鋼製
の部品について、疲労により亀裂が発生する前に、その
疲労度を測定することができる装置を開発したものであ
る。The present invention has been made to solve the above problems, and is an apparatus for measuring the degree of fatigue of austenitic stainless steel parts before cracks occur due to fatigue. Was developed.
【０００５】[0005]
【課題を解決するための手段】上記課題を解決するため
に成された本発明に係る疲労度測定装置は、 a)１本の強磁性体棒、強磁性体棒の略中央に巻かれた１
つの励磁コイル、及び、その両側に巻かれた２つの検出
コイルから成る検出部と、 b)上記励磁コイルに交流励磁電流を供給する励磁回路部
と、 c)上記２つの検出コイルを差動変圧器構成に接続し、そ
の出力信号を励磁電流の位相に基づいて位相解析するこ
とにより、オーステナイト系ステンレス鋼製の被検査物
の透磁率に応じた電気信号を取り出す処理回路部と、 d)処理回路部から取り出される電気信号の変化に基づ
き、オーステナイト系ステンレス鋼製の被検査物の疲労
度を算出する疲労度算出部と、を備えることを特徴とす
るものである。The fatigue degree measuring device according to the present invention, which has been made to solve the above-mentioned problems, comprises: a) one ferromagnetic rod, and the ferromagnetic rod is wound substantially in the center thereof. 1
One exciting coil and a detecting section consisting of two detecting coils wound on both sides thereof, b) an exciting circuit section for supplying an alternating exciting current to the exciting coil, and c) a differential transformer for the two detecting coils. Connected to the instrument configuration and performing phase analysis of the output signal based on the phase of the exciting current to obtain an electrical signal corresponding to the magnetic permeability of the austenitic stainless steel inspected object, and d) processing And a fatigue degree calculation section for calculating the fatigue degree of an austenitic stainless steel inspected object based on a change in an electric signal taken out from the circuit section.
【０００６】[0006]
【作用】本発明の疲労度測定装置の構成及び作用を図１
及び図２により説明する。検出部２は図２に示すように
１本の強磁性体棒２１、その略中央に巻かれた１つの励
磁コイル２２、及び、その両側に巻かれた２つの検出コ
イル２３、２４から成る。励磁コイルは励磁回路部４に
接続され、励磁回路部４より交流励磁電流の供給を受け
る。２つの検出コイル２３、２４は、励磁コイル２２と
共に差動変圧器構成となるように処理回路部３に接続さ
れている。なお、処理回路部３は励磁回路部４から励磁
電流の位相を表わす信号を受け取る。The structure and operation of the fatigue measuring device of the present invention is shown in FIG.
2 and FIG. As shown in FIG. 2, the detection unit 2 is composed of one ferromagnetic rod 21, one exciting coil 22 wound substantially in the center thereof, and two detection coils 23, 24 wound on both sides thereof. The exciting coil is connected to the exciting circuit unit 4 and is supplied with an alternating exciting current from the exciting circuit unit 4. The two detection coils 23 and 24 are connected to the processing circuit unit 3 so as to form a differential transformer configuration together with the exciting coil 22. The processing circuit section 3 receives a signal representing the phase of the exciting current from the exciting circuit section 4.
【０００７】励磁回路部４から検出部２の励磁コイル２
２に交流の励磁電流を供給すると、検出部２の強磁性体
棒２１の両端からは交番磁束が放出される。この検出部
２の一端を疲労していないオーステナイト系ステンレス
鋼製の被検査物１の表面に接触させると、被検査物１の
表面には渦電流が生成され、検出コイル２３、２４の両
端には渦電流により起電力が生成される。処理回路部３
は、励磁電流の位相に基づいて検出コイル２３、２４の
出力の位相解析を行なうことにより、被検査物１の透磁
率に応じた電気信号を取り出す。From the exciting circuit section 4 to the exciting coil 2 of the detecting section 2
When an alternating exciting current is supplied to 2, alternating magnetic flux is emitted from both ends of the ferromagnetic rod 21 of the detecting section 2. When one end of the detection unit 2 is brought into contact with the surface of the non-fatigue austenitic stainless steel DUT 1, an eddy current is generated on the surface of the DUT 1, and both ends of the detection coils 23 and 24 are generated. Generates electromotive force by eddy current. Processing circuit section 3
Performs a phase analysis of the outputs of the detection coils 23 and 24 based on the phase of the exciting current to extract an electric signal corresponding to the magnetic permeability of the DUT 1.
【０００８】被検査物１に多数回の繰り返し応力が加わ
り、疲労が進むと、被検査物１のオーステナイト相が加
工変態によりマルテンサイト相に変化する。これにより
被検査物１の透磁率が変化し、検出コイル２３、２４の
出力の位相状態が変化する。処理回路部３はこの位相状
態の変化を検出し、疲労度算出部５はこの変化に基づい
て被検査物１の疲労度を算出する。なお、本発明に係る
疲労度測定装置はこのような原理を利用するものである
ため、被検査物１の材質としてはマルテンサイト相への
加工変態が生じやすい準オーステナイト相を有するステ
ンレス鋼が望ましい。When stress is repeatedly applied to the object 1 to be inspected many times and fatigue progresses, the austenite phase of the object 1 is transformed into a martensite phase by work transformation. As a result, the magnetic permeability of the DUT 1 changes, and the phase states of the outputs of the detection coils 23 and 24 change. The processing circuit unit 3 detects the change in the phase state, and the fatigue degree calculation unit 5 calculates the fatigue degree of the inspection object 1 based on the change. Since the fatigue degree measuring device according to the present invention utilizes such a principle, the material of the inspection object 1 is preferably a stainless steel having a quasi-austenite phase that easily causes work transformation into a martensite phase. .
【０００９】[0009]
【発明の効果】本発明に係る疲労度測定装置では、オー
ステナイト系ステンレス鋼製の被検査物の相変化による
透磁率の変化を検出し、それに基づいて疲労度を測定す
るため、被検査物に亀裂が入る前に疲労が蓄積している
ことを検出することができる。すなわち、破壊が発生す
る前にその可能性を検出することができるため、亀裂の
存在を前提とした無駄に大きい安全率を設定する必要が
ない。また、疲労蓄積が検出された場合でも、実際に微
小な亀裂が発生する迄には長い時間がかかるため、検査
間隔を比較的長くとることができる。さらに、本発明に
係る疲労度測定装置は、亀裂自体が問題となるような部
品に対しても有効に対処することができる。In the fatigue degree measuring apparatus according to the present invention, the change in magnetic permeability due to the phase change of the object to be inspected made of austenitic stainless steel is detected, and the fatigue degree is measured based on the change in the magnetic permeability. It is possible to detect the accumulation of fatigue before it cracks. That is, since the possibility of destruction can be detected before it occurs, it is not necessary to set a uselessly large safety factor on the assumption of the presence of cracks. In addition, even if fatigue accumulation is detected, it takes a long time to actually generate a minute crack, so that the inspection interval can be relatively long. Furthermore, the fatigue degree measuring device according to the present invention can effectively deal with a component in which the crack itself poses a problem.
【００１０】[0010]
【実施例】本発明の一実施例を図３に示す。本実施例の
疲労度測定装置の基本的構成は図１及び２に示したもの
と同じであるため、同じ要素には同じ記号を使用する。
本実施例では、検出部２の強磁性体棒２１としては、直
径１ｍｍ、長さ１５ｍｍの軟鉄棒を使用する。処理回路
部３は、検出部２の２つの検出コイル２３、２４からの
電圧信号を加算し、増幅する入力回路３１、位相検波回
路３２及びローパスフィルタ３３から構成される。励磁
回路部４は正弦波電流発生回路４１と移相回路４２から
構成される。また、疲労度算出部５は、処理回路部３の
アナログ出力信号をデジタル値に変換するＡ／Ｄ変換器
５１、被検査物１の透磁率に応じた信号によって被検査
物１の疲労度を算出するためのＣＰＵ５２、及び、予め
鋼種毎の試験片等を用いて計測した、透磁率変化に応じ
た出力値と疲労度との関係のデータを格納しておくメモ
リ５３から構成される。FIG. 3 shows an embodiment of the present invention. Since the basic structure of the fatigue measuring device of this embodiment is the same as that shown in FIGS. 1 and 2, the same symbols are used for the same elements.
In this embodiment, as the ferromagnetic rod 21 of the detection unit 2, a soft iron rod having a diameter of 1 mm and a length of 15 mm is used. The processing circuit unit 3 includes an input circuit 31, a phase detection circuit 32, and a low-pass filter 33 that add and amplify voltage signals from the two detection coils 23 and 24 of the detection unit 2. The excitation circuit unit 4 is composed of a sine wave current generation circuit 41 and a phase shift circuit 42. Further, the fatigue degree calculation unit 5 calculates the fatigue degree of the inspection object 1 by an A / D converter 51 that converts the analog output signal of the processing circuit unit 3 into a digital value and a signal corresponding to the magnetic permeability of the inspection object 1. It is composed of a CPU 52 for calculation, and a memory 53 for storing the data of the relationship between the output value and the fatigue degree, which is measured in advance using a test piece for each steel type and the like, according to the change in permeability.
【００１１】本実施例の疲労度測定装置の作用は次の通
りである。まず、検出部２を被検査物１から遠く離した
状態で、正弦波電流発生回路４１から励磁コイル２２に
交流電流を流し、２つの検出コイル２３、２４に誘起さ
れる電圧の絶対値が同じになるように入力回路３１をバ
ランスさせて入力回路３１の出力電圧がゼロとなるよう
にする。その後、検出部２の強磁性体棒２１の一端を疲
労していないオーステナイト系ステンレス鋼製の被検査
物１の表面に接触させる。被検査物１は導電体であるた
め、励磁コイル２２によって発生する交流磁界に誘起さ
れて、接触部を中心とした渦電流が生成される。この渦
電流の影響により上記バランスが崩れ、２つの検出コイ
ル２３、２４の入力回路３１の出力電圧はゼロではなく
なる。入力回路３１の出力電圧は位相検波回路３２に送
られ、そこで移相回路４２からの基準ベクトル電圧信号
を基に位相解析される。このとき、位相検波回路３２の
出力がゼロとなるように位相検波回路３２のパラメータ
調整を行なっておく。The operation of the fatigue degree measuring apparatus of this embodiment is as follows. First, in a state in which the detection unit 2 is far away from the inspection object 1, an alternating current is caused to flow from the sine wave current generation circuit 41 to the exciting coil 22, and the absolute values of the voltages induced in the two detection coils 23 and 24 are the same. The input circuit 31 is balanced so that the output voltage of the input circuit 31 becomes zero. Then, one end of the ferromagnetic rod 21 of the detection unit 2 is brought into contact with the surface of the non-fatigue austenitic stainless steel DUT 1. Since the DUT 1 is a conductor, it is induced by the AC magnetic field generated by the exciting coil 22 to generate an eddy current centered on the contact portion. Due to the influence of this eddy current, the balance is lost and the output voltage of the input circuit 31 of the two detection coils 23 and 24 is not zero. The output voltage of the input circuit 31 is sent to the phase detection circuit 32, where the phase is analyzed based on the reference vector voltage signal from the phase shift circuit 42. At this time, the parameters of the phase detection circuit 32 are adjusted so that the output of the phase detection circuit 32 becomes zero.
【００１２】次に、上記被検査物１に多数回の繰り返し
負荷を加えて疲労させた後、強磁性体棒２１の上記一端
を被検査物１の上記と同じ箇所に接触させる。この場
合、被検査物１のオーステナイト相の一部は繰り返し負
荷により加工変態を生じ、マルテンサイトとなる。オー
ステナイト相は非磁性であるのに対しマルテンサイト相
は強磁性であるため、強磁性体棒２１の先端から放出さ
れる交番磁束により誘起される被検査物１の渦電流に変
化が生じ、検出コイル２３、２４の出力電圧の位相に僅
かの変化を生ずる。位相検波回路３２はこの位相変化を
検出し、出力する。位相検波回路３２の出力（アナロ
グ）はローパスフィルタ３３を通して疲労度算出部５の
Ａ／Ｄ変換器５１に送られ、デジタル値に変換される。
ＣＰＵ５２は、メモリ５３に格納されているデータを参
照することにより、位相検波回路３２の出力データに基
づいて被検査物１の疲労度を決定する。決定された疲労
度は、予め定められたフォーマットで表示装置６に表示
される。Next, after subjecting the object to be inspected 1 to repeated loading a number of times for fatigue, the one end of the ferromagnetic rod 21 is brought into contact with the same portion of the object to be inspected 1 as described above. In this case, part of the austenite phase of the inspection object 1 undergoes work transformation due to repeated loading and becomes martensite. Since the austenite phase is non-magnetic and the martensite phase is ferromagnetic, a change occurs in the eddy current of the DUT 1 induced by the alternating magnetic flux emitted from the tip of the ferromagnetic rod 21, and the detection is performed. It causes a slight change in the phase of the output voltage of the coils 23, 24. The phase detection circuit 32 detects this phase change and outputs it. The output (analog) of the phase detection circuit 32 is sent to the A / D converter 51 of the fatigue degree calculation unit 5 through the low pass filter 33 and converted into a digital value.
The CPU 52 refers to the data stored in the memory 53 to determine the fatigue level of the DUT 1 based on the output data of the phase detection circuit 32. The determined fatigue level is displayed on the display device 6 in a predetermined format.
【００１３】メモリ５３に格納しておく参照データの決
定方法の一例を次に説明する。まず、被検査物１と同じ
材質で図４に示すような試験片８を作成する。この試験
片８は、縦４８×横５０ｍｍの平板の中央に、負荷線か
らの深さが２４．５ｍｍの切り込み８１を入れたもの
で、切り込み８１の先端にはドリルで半径４ｍｍのアー
ルを付けておく。負荷用の孔８３、８４にピンを差し込
み、油圧式疲労試験機により切り込み８１が開く方向に
所定の振幅の荷重を繰り返し負荷する。所定回数毎に疲
労試験機を停止し、切り込み８１先端のアール部分８２
の先の方の疲労度を上記実施例の疲労測定装置で測定す
る。こうして、負荷の繰り返し回数とＡ／Ｄ変換器５１
のデジタル出力値のデータを多数採取し、グラフにプロ
ットすると、図５及び図６に示すようなグラフが得られ
る。図５はＳＵＳ３０４について得られた結果であり、
図６はＳＵＳ３１６について得られた結果である。いず
れの鋼種においても、負荷の繰り返し回数が増えるに従
ってＡ／Ｄ変換器５１のデジタル出力（すなわち、位相
検波回路３２の出力）の値は増加してゆく。また、その
増加の速度も繰り返し回数の増加に従って大きくなり、
或る時点で亀裂が発生する。なお、亀裂発生後は渦電流
の形状が大きく変化するため、位相検波回路３２の出力
も大きく変化する。従って、図５及び図６では亀裂発生
後のデータは記入していない。このようなデータをメモ
リ５３に格納しておくことにより、ローパスフィルタ３
３及びＡ／Ｄ変換器５１を経由した後の位相検波回路３
２の出力に基づいて疲労度を算出することができる。な
お、疲労度としてはそれまでの負荷回数（繰り返し回
数）を採用してもよいし、亀裂発生までの負荷回数、或
いは亀裂発生時の繰り返し回数を１とした指数等で表わ
してもよい。なお、図５、図６に示すように、鋼種によ
り繰り返し回数と位相検波回路３２の出力の関係は異な
るため、各種鋼種及び各種条件についてこのようなデー
タを作成しておき、メモリ５３に格納しておくことが望
ましい。そして、本疲労度測定装置を使用する際は、ど
の鋼種、どの条件で測定を行なうかを入力することによ
り、使用する参照データを決定し、それに基づいてＣＰ
Ｕ５２が疲労度を算出して表示装置６に表示を行なう。An example of the method of determining the reference data stored in the memory 53 will be described below. First, a test piece 8 as shown in FIG. 4 is made of the same material as the inspection object 1. This test piece 8 has a notch 81 having a depth of 24.5 mm from the load line in the center of a flat plate having a length of 48 mm and a width of 50 mm, and a radius of 4 mm is attached to the tip of the notch 81 with a drill. Keep it. A pin is inserted into the load holes 83 and 84, and a load having a predetermined amplitude is repeatedly applied in a direction in which the notch 81 opens by a hydraulic fatigue tester. The fatigue tester is stopped every predetermined number of times, and the radiused portion 82 at the tip of the notch 81 is cut.
The fatigue degree of the tip is measured by the fatigue measuring device of the above-mentioned embodiment. Thus, the number of times the load is repeated and the A / D converter 51
When a large amount of data of the digital output value of is collected and plotted on a graph, the graphs shown in FIGS. 5 and 6 are obtained. Figure 5 shows the results obtained for SUS304,
FIG. 6 is the result obtained for SUS316. In any steel type, the value of the digital output of the A / D converter 51 (that is, the output of the phase detection circuit 32) increases as the number of times the load is repeated increases. Also, the speed of increase increases as the number of repetitions increases,
At some point a crack develops. Since the shape of the eddy current changes greatly after the crack is generated, the output of the phase detection circuit 32 also changes greatly. Therefore, in FIGS. 5 and 6, the data after the occurrence of cracks is not entered. By storing such data in the memory 53, the low-pass filter 3
3 and the phase detection circuit 3 after passing through the A / D converter 51
The fatigue level can be calculated based on the output of 2. It should be noted that the fatigue count may be the load count (repetition count) up to that point, or may be represented by an index or the like in which the load count until the crack occurrence or the repeat count at the crack occurrence is 1. As shown in FIGS. 5 and 6, since the relationship between the number of repetitions and the output of the phase detection circuit 32 differs depending on the steel type, such data is created for various steel types and various conditions and stored in the memory 53. It is desirable to keep. When using this fatigue degree measuring apparatus, the reference data to be used is determined by inputting which steel type and under what conditions the measurement is to be performed, and based on that, the CP data is used.
U52 calculates the degree of fatigue and displays it on the display device 6.
【００１４】被検査物がオーステナイト系ステンレス鋼
製でない場合は、オーステナイト系ステンレス鋼製の薄
板をその被検査物に固定し、被検査物と同じ負荷の繰り
返しを受けるようにしておけば、本発明に係る疲労度測
定装置により、オーステナイト系ステンレス鋼製でない
被検査物についても、疲労度を測定することが可能とな
る。When the object to be inspected is not made of austenitic stainless steel, a thin plate made of austenitic stainless steel is fixed to the object to be inspected and subjected to the same load as the object to be inspected. With the fatigue degree measuring device according to the present invention, it is possible to measure the fatigue degree of an inspection object that is not made of austenitic stainless steel.
【図１】 本発明の構成を示すブロック図。FIG. 1 is a block diagram showing a configuration of the present invention.
【図２】 本発明の疲労度測定装置の検出部の概略構成
図。FIG. 2 is a schematic configuration diagram of a detection unit of the fatigue degree measuring device of the present invention.
【図３】 本発明の一実施例である疲労度測定装置の構
成を示すブロック図。FIG. 3 is a block diagram showing the configuration of a fatigue degree measuring device that is an embodiment of the present invention.
【図４】 参照データを作成するための疲労試験片の一
例の平面図。FIG. 4 is a plan view of an example of a fatigue test piece for creating reference data.
【図５】 ＳＵＳ３０４の参照データの一例のグラフ。FIG. 5 is a graph of an example of reference data of SUS304.
【図６】 ＳＵＳ３１６の参照データの一例のグラフ。FIG. 6 is a graph of an example of reference data of SUS316.
１…被検査物 ２…検出部 ２１…強磁性体棒 ２２…励磁コイル ２３、２４…検出コイル ３…処理回路部 ３１…入力回路 ３２…位相検波回路 ３３…ローパスフィルタ ４…励磁回路部 ４１…正弦波電流発生回路 ４２…移相回路 ５…疲労度算出部 ５１…Ａ／Ｄ変換器 ５２…ＣＰＵ ５３…メモリ ６…表示装置 ８…試験片 DESCRIPTION OF SYMBOLS 1 ... Inspected object 2 ... Detection part 21 ... Ferromagnetic rod 22 ... Excitation coil 23, 24 ... Detection coil 3 ... Processing circuit part 31 ... Input circuit 32 ... Phase detection circuit 33 ... Low pass filter 4 ... Excitation circuit part 41 ... Sine wave current generation circuit 42 ... Phase shift circuit 5 ... Fatigue degree calculation unit 51 ... A / D converter 52 ... CPU 53 ... Memory 6 ... Display device 8 ... Test piece
───────────────────────────────────────────────────── フロントページの続き (72)発明者 鷲見 和正 愛知県愛知郡長久手町大字長湫字横道41番 地の１ 株式会社豊田中央研究所内 (72)発明者 小松 嘉久 愛知県東海市荒尾町ワノ割１番地 愛知製 鋼株式会社内 (72)発明者 寒河江 孝志 愛知県東海市荒尾町ワノ割１番地 愛知製 鋼株式会社内 (72)発明者 福井 康二 愛知県東海市荒尾町ワノ割１番地 愛知製 鋼株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazumasa Washi Ai 41 Nagakute-cho, Aichi-gun, Aichi Prefecture, Nagatogi 1 1st side street, Toyota Central Research Institute Co., Ltd. (72) Inventor Yoshihisa Komatsu Wanowari, Arao-cho, Tokai-shi, Aichi No. 1 Aichi Steel Co., Ltd. (72) Inventor Takashi Sagae No. 1 Wano Wari, Arao-cho, Tokai City, Aichi Prefecture Aichi Steel Co., Ltd. (72) Koji Fukui No. 1 Wano Wari, Arao-cho, Tokai City, Aichi Within Steel Co., Ltd.
Claims (1)
央に巻かれた１つの励磁コイル、及び、その両側に巻か
れた２つの検出コイルから成る検出部と、 b)上記励磁コイルに交流励磁電流を供給する励磁回路部
と、 c)上記２つの検出コイルを差動変圧器構成に接続し、そ
の出力信号を励磁電流の位相に基づいて位相解析するこ
とにより、オーステナイト系ステンレス鋼製の被検査物
の透磁率に応じた電気信号を取り出す処理回路部と、 d)処理回路部から取り出される電気信号の変化に基づ
き、オーステナイト系ステンレス鋼製の被検査物の疲労
度を算出する疲労度算出部と、 を備えることを特徴とする疲労度測定装置。1. A detection unit comprising: a) one ferromagnetic rod, one exciting coil wound substantially in the center of the ferromagnetic rod, and two detection coils wound on both sides thereof. B. ) By connecting an exciting circuit section for supplying an alternating exciting current to the exciting coil, and c) connecting the two detecting coils to a differential transformer configuration, and analyzing the output signal based on the phase of the exciting current, Fatigue of the austenitic stainless steel inspected object based on the change of the electric signal taken out from the processing circuit section which takes out the electric signal according to the magnetic permeability of the austenitic stainless steel inspected object, and d) the processing circuit section. A fatigue degree measuring device comprising: a fatigue degree calculating unit for calculating the degree of fatigue.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP07990095A JP3910222B2 (en) | 1995-03-10 | 1995-03-10 | Fatigue measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP07990095A JP3910222B2 (en) | 1995-03-10 | 1995-03-10 | Fatigue measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08248004A true JPH08248004A (en) | 1996-09-27 |
| JP3910222B2 JP3910222B2 (en) | 2007-04-25 |
Family
ID=13703164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP07990095A Expired - Fee Related JP3910222B2 (en) | 1995-03-10 | 1995-03-10 | Fatigue measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3910222B2 (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004198246A (en) * | 2002-12-18 | 2004-07-15 | Nsk Ltd | Method for diagnosing load state of bearing |
| JP2004325246A (en) * | 2003-04-24 | 2004-11-18 | Toshiba Corp | Defect inspection apparatus |
| JP2009052997A (en) * | 2007-08-27 | 2009-03-12 | Maeda:Kk | Metal fatigue discrimination device and metal fatigue discrimination method |
| DE112010000023T5 (en) | 2009-12-17 | 2013-03-14 | Nsk Ltd. | A method for predicting a remaining life of a bearing, a device for diagnosing a remaining life of a bearing and bearing diagnostic system |
| US9234877B2 (en) | 2013-03-13 | 2016-01-12 | Endomagnetics Ltd. | Magnetic detector |
| US9239314B2 (en) | 2013-03-13 | 2016-01-19 | Endomagnetics Ltd. | Magnetic detector |
| US9427186B2 (en) | 2009-12-04 | 2016-08-30 | Endomagnetics Ltd. | Magnetic probe apparatus |
| US9808539B2 (en) | 2013-03-11 | 2017-11-07 | Endomagnetics Ltd. | Hypoosmotic solutions for lymph node detection |
| US10595957B2 (en) | 2015-06-04 | 2020-03-24 | Endomagnetics Ltd | Marker materials and forms for magnetic marker localization (MML) |
| US10634741B2 (en) | 2009-12-04 | 2020-04-28 | Endomagnetics Ltd. | Magnetic probe apparatus |
-
1995
- 1995-03-10 JP JP07990095A patent/JP3910222B2/en not_active Expired - Fee Related
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004198246A (en) * | 2002-12-18 | 2004-07-15 | Nsk Ltd | Method for diagnosing load state of bearing |
| JP2004325246A (en) * | 2003-04-24 | 2004-11-18 | Toshiba Corp | Defect inspection apparatus |
| JP2009052997A (en) * | 2007-08-27 | 2009-03-12 | Maeda:Kk | Metal fatigue discrimination device and metal fatigue discrimination method |
| US9427186B2 (en) | 2009-12-04 | 2016-08-30 | Endomagnetics Ltd. | Magnetic probe apparatus |
| US12092708B2 (en) | 2009-12-04 | 2024-09-17 | Endomagnetics Ltd. | Magnetic probe apparatus |
| US11592501B2 (en) | 2009-12-04 | 2023-02-28 | Endomagnetics Ltd. | Magnetic probe apparatus |
| US10634741B2 (en) | 2009-12-04 | 2020-04-28 | Endomagnetics Ltd. | Magnetic probe apparatus |
| DE112010000023B4 (en) | 2009-12-17 | 2021-09-30 | Nsk Ltd. | A method for predicting a remaining life of a bearing, an apparatus for diagnosing a remaining life of a bearing and a bearing diagnostic system |
| US8593138B2 (en) | 2009-12-17 | 2013-11-26 | Nsk Ltd. | Bearing residual life prediction method, bearing residual life diagnostic apparatus and bearing diagnostic system |
| DE112010000023T5 (en) | 2009-12-17 | 2013-03-14 | Nsk Ltd. | A method for predicting a remaining life of a bearing, a device for diagnosing a remaining life of a bearing and bearing diagnostic system |
| US9808539B2 (en) | 2013-03-11 | 2017-11-07 | Endomagnetics Ltd. | Hypoosmotic solutions for lymph node detection |
| US9523748B2 (en) | 2013-03-13 | 2016-12-20 | Endomagnetics Ltd | Magnetic detector |
| US9239314B2 (en) | 2013-03-13 | 2016-01-19 | Endomagnetics Ltd. | Magnetic detector |
| US9234877B2 (en) | 2013-03-13 | 2016-01-12 | Endomagnetics Ltd. | Magnetic detector |
| US10595957B2 (en) | 2015-06-04 | 2020-03-24 | Endomagnetics Ltd | Marker materials and forms for magnetic marker localization (MML) |
| US11504207B2 (en) | 2015-06-04 | 2022-11-22 | Endomagnetics Ltd | Marker materials and forms for magnetic marker localization (MML) |
| US12161513B2 (en) | 2015-06-04 | 2024-12-10 | Endomagnetics Ltd | Marker materials and forms for magnetic marker localization (MML) |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3910222B2 (en) | 2007-04-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6239593B1 (en) | Method and system for detecting and characterizing mechanical damage in pipelines using nonlinear harmonics techniques | |
| EP2707705B1 (en) | Surface property inspection device and surface property inspection method | |
| EP2124043B1 (en) | Eddy current inspection method and eddy current inspection device for carrying out the eddy current inspection method | |
| KR100218653B1 (en) | Electromagnetic Induction Tester | |
| CN101281168B (en) | Method for changing energize mode to realize different mode electromagnetic detection | |
| JPH08248004A (en) | Fatigue measuring device | |
| Aguila-Muñoz et al. | A magnetic perturbation GMR-based probe for the nondestructive evaluation of surface cracks in ferromagnetic steels | |
| JP2766929B2 (en) | Non-destructive inspection equipment | |
| WO2008072508A1 (en) | Nondestructive test instrument and nondestructive test method | |
| Wei et al. | A transducer made up of fluxgate sensors for testing wire rope defects | |
| Theiner et al. | Determination of residual stresses using micromagnetic parameters | |
| US5047717A (en) | Method and apparatus for measuring internal mechanical stress of a ferromagnetic body by determining the third harmonic of the induction | |
| CN112945427A (en) | Method for measuring two-dimensional stress at welding seam by utilizing Barkhausen effect and detection instrument | |
| KR101999945B1 (en) | Apparatus For Measuring Stess of ferromagnetic substance | |
| JPH0545184B2 (en) | ||
| JP3572452B2 (en) | Eddy current probe | |
| JP2000314728A (en) | Pulsed eddy current flaw detecting device | |
| Zhang et al. | Quantitative Study on Cross Section Damage of Steel Wire Rope Based on Magnetic Signal Characteristics Under Weak Magnetic Excitation | |
| EP1877767A2 (en) | Near fieldtm and combination near fieldtm - remote field electromagnetic testing (et) probes for inspecting ferromagnetic pipes and tubes such as those used in heat exchangers | |
| JPS59112257A (en) | Method and device for nondestructive inspection of ferromagnetic material | |
| JP4603216B2 (en) | Fatigue damage degree diagnosis method and fatigue damage degree diagnosis system for steel materials constituting steel structure | |
| JP2008002859A (en) | Nondestructive inspection method and apparatus for austenitic stainless steel | |
| JPH01269049A (en) | Method of inspecting deterioration of metallic material | |
| Bernieri et al. | Improving non-destructive testing probe performance by digital processing techniques | |
| JP7454165B2 (en) | Magnetic material measurement probe and magnetic material measurement device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20040302 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040428 |
|
| A911 | Transfer of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20040511 |
|
| A912 | Removal of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A912 Effective date: 20040618 |
|
| A521 | Written amendment |
Effective date: 20060922 Free format text: JAPANESE INTERMEDIATE CODE: A821 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20070124 |
|
| R150 | Certificate of patent (=grant) or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| LAPS | Cancellation because of no payment of annual fees |