JPS59135363A - Ultrasonic flaw detection of small diameter thin walled pipe - Google Patents
Ultrasonic flaw detection of small diameter thin walled pipeInfo
- Publication number
- JPS59135363A JPS59135363A JP58010289A JP1028983A JPS59135363A JP S59135363 A JPS59135363 A JP S59135363A JP 58010289 A JP58010289 A JP 58010289A JP 1028983 A JP1028983 A JP 1028983A JP S59135363 A JPS59135363 A JP S59135363A
- Authority
- JP
- Japan
- Prior art keywords
- flaw detection
- probe
- defect
- probes
- steel pipe
- 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.)
- Pending
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
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/24—Probes
- G01N29/2487—Directing probes, e.g. angle probes
-
- 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
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/26—Arrangements for orientation or scanning by relative movement of the head and the sensor
- G01N29/275—Arrangements for orientation or scanning by relative movement of the head and the sensor by moving both the sensor and the material
-
- 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
- G01N2291/023—Solids
- G01N2291/0237—Thin materials, e.g. paper, membranes, thin films
-
- 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
- G01N2291/042—Wave modes
- G01N2291/0423—Surface waves, e.g. Rayleigh waves, Love 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
- G01N2291/04—Wave modes and trajectories
- G01N2291/044—Internal reflections (echoes), e.g. on walls or defects
-
- 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
- G01N2291/056—Angular incidence, angular propagation
-
- 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
- G01N2291/26—Scanned objects
- G01N2291/263—Surfaces
- G01N2291/2634—Surfaces cylindrical from outside
-
- 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
- G01N2291/26—Scanned objects
- G01N2291/263—Surfaces
- G01N2291/2636—Surfaces cylindrical from inside
Landscapes
- Physics & Mathematics (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)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、小径薄肉管における内外面欠陥を弁別可能に
探傷する方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting defects on the inner and outer surfaces of small-diameter thin-walled tubes in a distinguishable manner.
ある。すなわち、前記探傷により内外面欠陥を検出した
場合には、その内外面欠陥を弁別し、該欠陥部分に異な
った色のマーキングを施こし、前記欠陥が手入ｎの出来
る程度の軽微なものであｎば欠陥手入ｎを行ない、また
欠陥手入ｎが出来ないものであｎば廃却することにより
成品の品質の安定を図っている。be. That is, when an inner and outer surface defect is detected by the above-mentioned flaw detection, the inner and outer surface defects are distinguished, and the defective part is marked with a different color to determine whether the defect is a minor one that can be cleaned. We aim to stabilize the quality of finished products by taking care of defects if they occur, and by discarding products that cannot be repaired for defects.
ところで、肉厚が、例えば３ｍｍ以上の鋼管の場合ｖｅ
は、探触子回転方式あるいは鋼戸回転方式による斜角探
傷を行なうと内外面欠陥の探傷波形は第１図（イ）（ロ
）に宗す如くになる。すなわち、肉厚が３燗以上の鋼管
（１）の場合は、探傷器ブラウン管の横軸Ｃ時間軸）上
における内面欠陥（４）（第１図（イ））と外面欠陥（
５）（第１図（ロ））の信号出力位置が異なり、よって
こｎらに個別のゲート回路を設定することにより、内外
面欠陥を別々に記録でき内外面欠陥の弁別は可能であっ
た。これは、第１図（イ）（ロ）に示す様に内面欠陥は
α５スキップ位置で最もエコーが高くなり、また、外面
欠陥はＬＯスキップ位置で超音波ビームが直接外面欠陥
に当った場合にエコーが高くなり、他のところではエコ
ーが低いことによるものである。By the way, in the case of a steel pipe with a wall thickness of 3 mm or more, for example,
When angle flaw detection is performed using a rotating probe method or a rotating steel door method, the waveforms for detecting internal and external defects become similar to those shown in FIGS. 1(a) and 1(b). In other words, in the case of a steel pipe (1) with a wall thickness of 3 mm or more, the inner surface defect (4) (Fig. 1 (a)) and the outer surface defect (
5) (Figure 1 (b)) The signal output positions are different, so by setting individual gate circuits for these, it was possible to record internal and external defects separately and to distinguish between internal and external defects. . This is because, as shown in Figure 1 (a) and (b), for internal defects, the echo is highest at the α5 skip position, and for external defects, when the ultrasonic beam directly hits the external defect at the LO skip position, This is due to high echoes and low echoes elsewhere.
しかし、鋼管が小径管で、かつその肉厚が１ｍ前後の薄
肉管の場合には、内外面欠陥の探傷波形は第２図（イ）
←）に示す様に連続的に現わ汎、前記し極めて困峙てあ
った。However, if the steel pipe is a small-diameter pipe with a wall thickness of around 1 m, the waveform for detecting internal and external defects will be as shown in Figure 2 (A).
As shown in ←), these problems appeared continuously, and as mentioned above, were extremely difficult.
従って、現状では第２図に示す様に１つのゲート回路を
表面エコーＣ以下「Ｓエコー」と云う）直後に設定して
内外面欠陥を一緒に取如出し、しかる後マーカを作動さ
せて鋼管（１）表面にマーキングを施こし、手入ｎ作業
者に情報として提供しているに留まっている。しかし、
前記した様な方法では内外面欠陥の弁別はできていなか
った為に、マーキング箇所で−Ｈ製造ラインを停止させ
るか、あるいは検査終了後一本づつ丹念に目視で内外面
欠陥の弁別を行ない外面にあって軽度らしき欠陥の場合
は手入ｎを行ない、また外表面の欠陥ではないと判断さ
ｎた場合には廃却するという方法を採っていた。このよ
うに、従来の方法では極めて作業性が悪く、また目視に
よる検査が介入する為に信頼性に欠けるという欠点があ
った。Therefore, at present, as shown in Figure 2, one gate circuit is set immediately after the surface echo C (hereinafter referred to as "S echo") to take out the inner and outer defects together, and then the marker is activated to detect the steel pipe. (1) Markings are only made on the surface and provided as information to maintenance workers. but,
Since it was not possible to distinguish between internal and external defects using the methods described above, we either stopped the -H production line at the marking point, or after the inspection was completed, we carefully visually identified defects on the internal and external surfaces one by one. In the case of a minor defect, the product was cleaned, and if it was determined that the defect was not on the outer surface, the product was discarded. As described above, the conventional method has the drawbacks of extremely poor workability and lack of reliability due to the intervention of visual inspection.
本発明は上記問題点に鑑みて成ざｎたものであり、小径
薄肉管における内外面欠陥を精度良く弁別可能に探傷す
る方法を提供せんとするものである。The present invention was developed in view of the above-mentioned problems, and it is an object of the present invention to provide a method for detecting defects on the inner and outer surfaces of small-diameter thin-walled tubes in a manner that allows accurate discrimination.
すなわち、本発明は管回転方式あるいは探触子回転方式
による小径薄肉管の内外面欠陥探傷方法であって、被検
査管の内外面欠陥を探傷する為の斜角探傷用探触子と、
同じ′く外面欠陥のみを探傷する為の表面波探傷用探触
子の配置を同方向同一平面内において所要の角度を存し
て設置するか、又は周方向同一角度内において所要の管
軸方向距離を隔てて設置するか、あるいは所要の角度と
距離を存して設置する等両探触子の位置あるいは両探触
子の成す角度に関連づけ１両探触子夫々で探傷を行ない
内外面欠陥を弁別探傷することを要旨とする超音波探傷
方法である。That is, the present invention is a method for detecting defects on the inner and outer surfaces of a small-diameter thin-walled tube using a tube rotation method or a probe rotation method, which comprises: an angle-angle flaw detection probe for detecting defects on the inner and outer surfaces of a tube to be inspected;
Similarly, surface wave flaw detection probes for detecting only external defects can be placed in the same direction and on the same plane at the required angle, or in the same circumferential direction and in the required tube axis direction. Flaws can be detected on internal and external surfaces by performing flaw detection with each probe in relation to the position of both probes or the angle formed by both probes, such as by installing them at a distance or at a required angle and distance. This is an ultrasonic flaw detection method whose main purpose is to perform discriminative flaw detection.
以下本発明方法を第３図以降の添付図面に基づいて説明
する。The method of the present invention will be explained below based on the accompanying drawings starting from FIG.
第３図は、本発明方法を実施するための探触子の配置関
係を示す一実施例であり、小径薄肉管（１）Ｃ以下単に
「鋼管（１）」と云う）の同一円周上に２個の探触子（
２０３）を所要の角度（萄だけ隔して配置した例を示し
ている。すなわち、一方の探触子（２）は鋼管（１）の
内外面欠陥を探傷するための斜角探傷用探触子であり、
他方の探触子（３）は鋼管（１）の外面欠陥のみを探傷
するための表面波探触子である。もちろん、前記両探触
子（２＋ （３）と鋼管（１）との間には超音波接触媒
体である水が媒介ｇｎでおり％また両探触子（２）（３
）は直進し℃くる鋼管（１）の外周を回転せしめらする
か、あるいは鋼管（１）が回転せしめらｎながら搬送さ
ｎでくるかの、いわゆる超音波ビーム軌跡がスパイラル
状になっているものである。FIG. 3 shows an example of the arrangement of probes for carrying out the method of the present invention, in which probes are placed on the same circumference of a small-diameter thin-walled pipe (1) (hereinafter simply referred to as "steel pipe (1)"). 2 probes (
203) are arranged at a required angle (separated by the ribs. In other words, one probe (2) is an angle probe for detecting flaws on the inner and outer surfaces of the steel pipe (1). is a child,
The other probe (3) is a surface wave probe for detecting only external defects of the steel pipe (1). Of course, between the two probes (2+ (3) and the steel pipe (1), water, which is an ultrasonic coupling medium, is used as a medium gn).
) travels straight and rotates the outer periphery of the steel pipe (1), or the steel pipe (1) rotates while being conveyed, so the so-called ultrasonic beam trajectory has a spiral shape. It is something.
前記斜角探傷用探触子（２）から入射さｎた縦波は、鋼
管（１）に入射し屈折角度４５°の横波で鋼管（１）の
周方向にジグザグ状にスキップしながら法搬する。この
場合には下記の０式が成立することが知らｎている。The longitudinal wave incident from the angle angle flaw detection probe (2) enters the steel pipe (1) and is propagated as a transverse wave with a refraction angle of 45° while skipping in a zigzag pattern in the circumferential direction of the steel pipe (1). do. In this case, it is known that the following equation 0 holds true.
０１／ｍ １＝ ａ□／ｌｈθ ・
・・■但し、１：入射角
θ：屈折角
０１：水中の音速（縦波）
１４９０ ｍ／５ｅｃ
Ｃ２：鋼中の音速（横波〕
３２００ ｍ／ｓｅｃ
よって、屈折角θを４５とすｎは前記０式より入射角１
ば１９となる。01/m 1= a□/lhθ ・
...■ However, 1: Incident angle θ: Refraction angle 01: Sound speed in water (longitudinal wave) 1490 m/5ec C2: Sound speed in steel (transverse wave) 3200 m/sec Therefore, if the refraction angle θ is 45, n is From the above formula 0, the angle of incidence is 1
It becomes 19.
また、表面波探触子（３）により表面波を発生させる場
合には屈折角θは約９０°となる為前記の式より入射角
１は２７である。ここで、前記表面波探触子（３）から
入射ざ扛る表面波は鋼管（１）の表面層のみを伝播する
波である為、鋼管（１）の肉厚が１ｍｎ程度であっても
周波数が４〜５ Ｍｕｚでは内表面に迄は到達しないも
のである。従って、第３図０）に示す様に鋼管（１）内
周面に存在する欠陥（４）は、斜角探傷用探触子（２）
では検出さ汎るが、表面波探触子（３）では検出されな
いことになる。また、第３図（ロ）に示す様に鋼管（１
）外周面に存在する欠陥（５）は、両探触子（２）（３
）で検出されることになる。Further, when a surface wave is generated by the surface wave probe (3), the refraction angle θ is approximately 90°, so the incident angle 1 is 27 from the above equation. Here, since the surface waves incident and rippled from the surface wave probe (3) are waves that propagate only through the surface layer of the steel pipe (1), even if the wall thickness of the steel pipe (1) is about 1 mm, When the frequency is 4 to 5 Muz, it does not reach the inner surface. Therefore, as shown in Fig. 3 (0), the defect (4) existing on the inner peripheral surface of the steel pipe (1) can be detected by the angle probe (2).
However, it is not detected by the surface wave probe (3). In addition, as shown in Figure 3 (b), steel pipes (1
) Defects (5) present on the outer circumferential surface of both probes (2) (3
) will be detected.
この両者の出力信号を時間的に同期させ比較する。つま
り、両者の出力信号が時間的に同一位置に出力すｎば外
面欠陥（５）と判断し、−また斜角探傷用探触子（２）
の信号のみであ几は内面欠陥（４）と判断する。そして
所定判別基準の信号レベル以上のもののみを警報器に出
力させるか、または内外面欠陥用の個々の表示マーカに
入力させることにより自動的に弁別が可能となる。These two output signals are temporally synchronized and compared. In other words, if both output signals are output at the same position in time, it is determined that there is an external surface defect (5), and the bevel probe (2) is detected.
Based on only this signal, the detector determines that there is an inner surface defect (4). Then, automatic discrimination becomes possible by outputting only those signals having a signal level equal to or higher than a predetermined discrimination standard to an alarm device or inputting them to individual display markers for internal and external defects.
なお、第４図に示すように両探触子（２）（３）を管軸
方向に距離Ｔだけ離して設置した場合には、搬送さルて
くる鋼管（１）にローラ（図示せず）を接触させ、この
ローラが回転したときにパルス信号を発生する例えばパ
ルスジェネレータ（図示せず）を設置して前記距離Ｔを
搬送するに要する時間′ｆｔ測定し、両者の時間ず几を
補正し信号処理上で同期させ几ば管軸方向のす′ｎは解
消ざ几る。In addition, when both the probes (2) and (3) are installed a distance T apart in the tube axis direction as shown in Fig. 4, a roller (not shown) is attached to the steel tube (1) being conveyed. ) and install a pulse generator (not shown) that generates a pulse signal when this roller rotates, measure the time 'ft required to convey the distance T, and correct the time difference between the two. However, if the signal processing is synchronized, the distortion in the tube axis direction will be eliminated.
また、第３図に示す様に周方向における両探触子（２）
（３）の位相差が角度Δだけある場合にも、前記第４
図における説明の場合と同様の処理を行なえば周方向の
ずれは解消でき正確な弁別探傷が行なえる。Also, as shown in Figure 3, both probes (2) in the circumferential direction
Even when the phase difference in (3) is the angle Δ, the fourth
By performing the same process as in the explanation in the figure, the deviation in the circumferential direction can be eliminated and accurate discrimination flaw detection can be performed.
以上述べた如く、本発明方法によｎば比較的容易な方法
で小径薄肉管における内外面欠陥の正確な弁別探傷が可
能となり、手入ｎ作業を効率良く行なうことが出来る等
極めて大なる効果を有する発明である。As described above, the method of the present invention enables accurate discrimination detection of internal and external surface defects in small-diameter thin-walled pipes in a relatively easy manner, and has extremely large effects such as being able to perform maintenance work efficiently. This invention has the following.
第１図は従来の探傷方法で厚肉管の内外面欠陥を探傷し
た場合の説明図と波形図であり、同図（イ）は内面欠陥
、同図（ロ）は外面欠陥、第２図は同様の方法で薄肉管
の内外面欠陥を探傷した場合の説明図と波形図であり、
同図（イ）は外面欠陥、同図（ロ）は内面欠陥、第３図
は本発明方法の説明図であり、同図（イ）は内面欠陥の
探傷時、同図（ロ）は外面欠陥の探傷時、第４図は探触
子の配置関係の例を示した説明図である。
（１）は鋼管、（２）は斜角探傷用探触子、（３）は表
面波探触子、（４）は内面欠陥、（５）は外面欠陥。
ＴＳ ケ”）Figure 1 is an explanatory diagram and a waveform diagram when defects on the inner and outer surfaces of a thick-walled pipe are detected using a conventional flaw detection method. are an explanatory diagram and a waveform diagram when defects on the inner and outer surfaces of a thin-walled pipe are detected using the same method.
The figure (A) shows the external defect, the figure (B) shows the inner surface defect, and Figure 3 is an explanatory diagram of the method of the present invention. FIG. 4 is an explanatory diagram showing an example of the arrangement of probes during defect detection. (1) is a steel pipe, (2) is an angle angle flaw detection probe, (3) is a surface wave probe, (4) is an internal defect, and (5) is an external defect. TS ke”)
Claims (1)
径薄肉管の内外面欠陥探傷方法であって、被検査管の内
外面欠陥を探傷する為の斜角探傷用探触子と、同じく外
面欠陥を探傷する為の表面波探傷用探触子を配置して両
探触子夫々で探傷を行ない、こｎら両探触子の位置ある
いは両探触子の成す角度に関連づけて内外面欠陥を弁別
探傷することを特徴とする小径薄肉管の超音波探傷方法
。(1) A method for detecting defects on the inner and outer surfaces of small-diameter thin-walled tubes using a tube rotation method or a probe rotation method, which uses an angle probe for detecting defects on the inner and outer surfaces of the tube to be inspected, and also detects defects on the outer surface. Surface wave flaw detection probes are placed to detect flaws, and flaw detection is performed with both probes individually.Flaws on the inner and outer surfaces are detected in relation to the position of both probes or the angle formed by both probes. An ultrasonic flaw detection method for small-diameter thin-walled pipes characterized by differential flaw detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58010289A JPS59135363A (en) | 1983-01-24 | 1983-01-24 | Ultrasonic flaw detection of small diameter thin walled pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58010289A JPS59135363A (en) | 1983-01-24 | 1983-01-24 | Ultrasonic flaw detection of small diameter thin walled pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59135363A true JPS59135363A (en) | 1984-08-03 |
Family
ID=11746141
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58010289A Pending JPS59135363A (en) | 1983-01-24 | 1983-01-24 | Ultrasonic flaw detection of small diameter thin walled pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59135363A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6273261U (en) * | 1985-10-29 | 1987-05-11 | ||
| EP0359993A2 (en) * | 1988-09-21 | 1990-03-28 | Robert Bosch Gmbh | Alarm installation to recognize defects in moving parts |
| JPH04265853A (en) * | 1990-10-24 | 1992-09-22 | Babcock & Wilcox Co:The | Method and apparatus for identifying flaw depth in checking of tubular product |
| CN114280144A (en) * | 2021-11-17 | 2022-04-05 | 东方电气集团东方锅炉股份有限公司 | Angle-rotatable ultrasonic probe and ultrasonic detection method for weld defects |
-
1983
- 1983-01-24 JP JP58010289A patent/JPS59135363A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6273261U (en) * | 1985-10-29 | 1987-05-11 | ||
| EP0359993A2 (en) * | 1988-09-21 | 1990-03-28 | Robert Bosch Gmbh | Alarm installation to recognize defects in moving parts |
| JPH04265853A (en) * | 1990-10-24 | 1992-09-22 | Babcock & Wilcox Co:The | Method and apparatus for identifying flaw depth in checking of tubular product |
| CN114280144A (en) * | 2021-11-17 | 2022-04-05 | 东方电气集团东方锅炉股份有限公司 | Angle-rotatable ultrasonic probe and ultrasonic detection method for weld defects |
| CN114280144B (en) * | 2021-11-17 | 2023-12-08 | 东方电气集团东方锅炉股份有限公司 | Rotatable angle ultrasonic probe and weld defect ultrasonic detection method |
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