CN110308210B - Sensitivity calibration sample tube for detecting tube bundle defects of nonferromagnetic heat exchanger by far-field eddy current and acoustic pulse - Google Patents
Sensitivity calibration sample tube for detecting tube bundle defects of nonferromagnetic heat exchanger by far-field eddy current and acoustic pulse Download PDFInfo
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- CN110308210B CN110308210B CN201910687098.5A CN201910687098A CN110308210B CN 110308210 B CN110308210 B CN 110308210B CN 201910687098 A CN201910687098 A CN 201910687098A CN 110308210 B CN110308210 B CN 110308210B
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- 230000007547 defect Effects 0.000 title claims abstract description 45
- 230000035945 sensitivity Effects 0.000 title claims abstract description 18
- 238000001514 detection method Methods 0.000 claims abstract description 44
- 230000005294 ferromagnetic effect Effects 0.000 claims abstract description 10
- 238000005070 sampling Methods 0.000 claims 1
- 239000000523 sample Substances 0.000 abstract description 14
- 238000004519 manufacturing process Methods 0.000 abstract description 6
- 238000005259 measurement Methods 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 9
- 238000000034 method Methods 0.000 description 6
- 239000004020 conductor Substances 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000005291 magnetic effect Effects 0.000 description 3
- 238000009659 non-destructive testing Methods 0.000 description 3
- 239000003208 petroleum Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005672 electromagnetic field Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000000414 obstructive effect Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/82—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws
- G01N27/90—Investigating 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
- G01N27/9006—Details, e.g. in the structure or functioning of sensors
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- 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
- G01N29/30—Arrangements for calibrating or comparing, e.g. with standard objects
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- 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
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/028—Material parameters
- G01N2291/0289—Internal structure, e.g. defects, grain size, texture
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Abstract
The invention relates to a sensitivity calibration sample tube for detecting tube bundle defects of a non-ferromagnetic heat exchanger by using far-field eddy current and acoustic pulse, belonging to the field of pipeline nondestructive detection. Three artificial defect through holes I, III and V are arranged along the axial direction of the cylindrical pipe body, wherein the artificial defect through holes II are positioned between the first through hole and the third through hole and are separated by 120 degrees clockwise along the circumferential direction, and the artificial defect through holes IV are positioned between the third through hole and the fifth through hole and are separated by 120 degrees anticlockwise along the circumferential direction. The advantage is novel structure, according to the common defect type of non-ferromagnetic heat exchanger tube bank manufacturing, during operation, the manual manufacture is different defects on same sensitivity adjustment pipe, can realize simultaneously on a sample pipe that debugging is carried out to far field vortex probe and acoustic pulse detection, has improved detection efficiency by a wide margin, has solved the problem such as need change pipe in traditional detection method, has improved work efficiency, convenient and fast is fit for the quick measurement of multiple pipelines.
Description
Technical Field
The invention belongs to the field of nondestructive detection of pipelines, and particularly relates to a sensitivity calibration sample tube for detecting defects of a tube bundle of a non-ferromagnetic heat exchanger by using far-field eddy current and acoustic pulse.
Background
Heat exchanger bundles find wide application in petroleum, chemical, electrical and other industries. Frequent leakage of heat exchanger tube bundles in petroleum, chemical industry, electric power and other industries results in production stoppage, so that economic loss of enterprises is caused, and life safety of on-site workers is even threatened. Because various defects can be generated in the manufacturing, mounting, service and other processes of the heat exchanger tube bundles, potential safety hazards are brought to a pipeline transportation system, pipelines are frequently leaked, unplanned production stoppage is caused, and huge economic loss of enterprises is caused, and even life safety of on-site workers is threatened. Therefore, nondestructive testing technology or equipment can be rapidly and effectively carried out on the service pipeline, and the nondestructive testing technology or equipment is attracting attention.
At present, the conventional nondestructive testing method for the tube bundle channels of the non-ferromagnetic heat exchanger is a common eddy current testing technology and an acoustic pulse testing technology; wherein:
(1) And (3) acoustic pulse detection:
when the acoustic pulse detection is needed, the right side of the probe is inserted into a detected pipe, an acoustic pulse detection waveform diagram is pressed by an acoustic pulse detection button on the probe, a high-frequency loudspeaker sends out a series of excitation pulse waves in the process of propagating along a pipeline, when the acoustic pulse waves encounter a blockage or a defect, a reflection echo is generated, an audio sensor acquires the echo signals, the echo signals are sent to an analysis system after frequency selection filtering treatment and display waveforms, penetrating defects such as holes and cracks penetrating through the pipe wall, and the phase of the echo signals is positive after negative: obstructive defects, including pits, plugs, pipe deformations, etc., the echo signal phase is positive and negative.
(2) Far field eddy current detection:
the eddy current detection is a nondestructive detection method based on the electromagnetic induction principle, and is suitable for conductive materials. When a conductor is placed in an alternating magnetic field, an induced current is present in the conductor, i.e. eddy currents are generated. The detection method for judging the property and state of the conductor by utilizing the phenomenon is called eddy current detection, wherein the eddy current is caused to change due to the change of various factors (such as conductivity, magnetic permeability, shape, size, defects and the like) of the conductor.
Detection principle: the principle of far-field eddy current technology works is to detect changes in the alternating magnetic field emitted by the sensor. The electromagnetic field is sent out by the sensor to act on the metal pipeline and is enhanced at the place with metal loss, the electromagnetic field is received by the receiving sensor, converted by the analog-to-digital converter and processed by the digital processor. The detection data is stored in the detector.
Through the analysis, the common vortex detection efficiency is high; high detection speed and 100% detection; has high sensitivity to corrosion type defects. However, the conventional vortex has lower sensitivity to detect the blocking type defect and the perforation type defect in the pipe. In addition, the conventional vortex technology is directly applied to detection of a heat exchanger tube bundle, and for example, the conventional vortex technology cannot distinguish between defects of the outer wall and internal defects of the tube, and cannot detect blind areas existing near the blocked tube and the tube sheet. The acoustic pulse detection technology has higher sensitivity for detecting the blocking type defect and the perforation type defect in the pipe, has the advantages of long detection distance, large detection coverage, high detection speed, no influence of pipe materials and the like, can make up the defect of far-field vortex, is insensitive to internal corrosion, cannot detect the external corrosion of the pipe,
according to the related standard, the common vortex detection and the acoustic pulse detection are different in detection defect type and sensitivity, so that if two technologies are combined, the defects meeting the requirements of the common vortex detection and the acoustic pulse detection are required to be designed on one sensitivity calibration sample tube.
Disclosure of Invention
The invention provides a sensitivity calibration sample tube for detecting defects of a tube bundle of a non-ferromagnetic heat exchanger by using far-field eddy current and acoustic pulse at the same time, so as to solve the problem that the defects required by the far-field eddy current detection and the acoustic pulse detection are not met on one sensitivity calibration sample tube at present.
The technical scheme adopted by the invention is as follows: three artificial defect through holes I, three and five are arranged along the axial direction of the cylindrical pipe body, the length of the pipe body is 1000mm, the distance between the first through hole and the left end of the pipe body is less than or equal to 100mm, and the distance between the fifth through hole and the right end of the pipe body is less than or equal to 100mm; the artificial defect through hole II is positioned between the through hole I and the through hole III, and is separated by 120 degrees clockwise along the circumferential direction, the artificial defect through hole IV is positioned between the through hole III and the through hole V, and is separated by 120 degrees anticlockwise along the circumferential direction, and the apertures of the through hole I, the through hole II, the through hole III, the through hole IV and the through hole V are all the same;
the third through hole is positioned at the midpoint of the first through hole and the fifth through hole;
the axial distance between the second through hole and the third through hole is 50mm;
the axial distance between the through holes IV and III is 50mm;
when the outer diameter d of the pipe body is less than or equal to 10mm, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 0.4mm; when d is more than 10 and less than or equal to 20, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 0.6mm; when d is more than 20 and less than or equal to 30, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 0.8mm; when d is more than 30 and less than or equal to 40, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 1.0mm; and when d is more than 40 and less than or equal to 50, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 1.2mm.
The invention has the advantages that the structure is novel, different defects are manually manufactured on the same sensitivity adjusting sample tube according to common defect types during the manufacturing and operation of the non-ferromagnetic heat exchanger tube bundle, the debugging of the far-field eddy current probe and the sound pulse detection can be simultaneously realized on one sample tube, the detection efficiency is greatly improved, the problems that the sample tube needs to be replaced in the traditional detection method are solved, the working efficiency is improved, the method is convenient and quick, the method is suitable for multi-pipeline rapid measurement, and the method can be widely applied to the rapid detection of the non-ferromagnetic heat exchanger tube bundle in the fields of petroleum, chemical industry, electric power, steel factories and the like.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a cross-sectional view A-A of FIG. 1;
FIG. 3 is a sectional view B-B of FIG. 1;
fig. 4 is a C-C cross-sectional view of fig. 1.
Detailed Description
Three artificial defect through holes I2, through holes III 4 and through holes V6 are formed along the axial direction of the cylindrical pipe body 1, the length of the pipe body 1 is 1000mm, the distance between the through holes I2 and the left end of the pipe body is less than or equal to 100mm, and the distance between the through holes V6 and the right end of the pipe body is less than or equal to 100mm; the artificial defect through hole II is positioned between the through hole I2 and the through hole III 4 and is separated by 120 degrees clockwise along the circumferential direction, the artificial defect through hole IV 5 is positioned between the through hole III 4 and the through hole V6 and is separated by 120 degrees anticlockwise along the circumferential direction, and the apertures of the through hole I2, the through hole II 3, the through hole III 4, the through hole IV 5 and the through hole V6 are all the same;
the third through hole 4 is positioned at the midpoint of the connection line between the first through hole 2 and the fifth through hole 6;
the axial distance between the second through hole 3 and the third through hole 4 is 50mm;
the axial distance between the through hole IV 5 and the through hole III 4 is 50mm;
when the outer diameter d of the pipe body 1 is less than or equal to 10mm, the apertures of the first through hole 2, the second through hole 3, the third through hole 4, the fourth through hole 5 and the fifth through hole 6 are 0.4mm; when d is more than 10 and less than or equal to 20, the apertures of the first through hole 2, the second through hole 3, the third through hole 4, the fourth through hole 5 and the fifth through hole 6 are 0.6mm; when d is more than 20 and less than or equal to 30, the apertures of the first through hole 2, the second through hole 3, the third through hole 4, the fourth through hole 5 and the fifth through hole 6 are 0.8mm; when d is more than 30 and less than or equal to 40, the apertures of the first through hole 2, the second through hole 3, the third through hole 4, the fourth through hole 5 and the fifth through hole 6 are 1.0mm; and when d is more than 40 and less than or equal to 50, the apertures of the first through hole 2, the second through hole 3, the third through hole 4, the fourth through hole 5 and the fifth through hole 6 are 1.2mm.
Working principle:
detecting the artificial defect through hole III 4 by using an acoustic pulse detection instrument, adjusting equipment parameters to enable the acoustic pulse detection equipment to detect the defect of the through hole III 4, and saving related parameters, wherein the sensitivity is higher;
detecting defects of the first through hole 2, the second through hole 3, the third through hole 4, the fourth through hole 5 and the fifth through hole 6 which are artificial defects by using a far-field eddy current detection instrument, adjusting equipment parameters to enable acoustic pulse detection equipment to detect corresponding defects, enabling sensitivity to be high, and storing related parameters;
and then in the field detection, the on-site pipe to be detected is detected by using the related parameters of the two devices, and the invention can simultaneously provide related samples required by executing the standard detection for the two detection methods and completely meet the standard.
Claims (3)
1. A sensitivity calibration sampling tube for detecting defects of a tube bundle of a non-ferromagnetic heat exchanger by using far-field eddy current and acoustic pulse simultaneously is characterized in that: three artificial defect through holes I, three and five are arranged along the axial direction of the cylindrical pipe body, the length of the pipe body is 1000mm, the distance between the first through hole and the left end of the pipe body is less than or equal to 100mm, and the distance between the fifth through hole and the right end of the pipe body is less than or equal to 100mm; the artificial defect through hole II is positioned between the through hole I and the through hole III, and is separated by 120 degrees clockwise along the circumferential direction, the artificial defect through hole IV is positioned between the through hole III and the through hole V, and is separated by 120 degrees anticlockwise along the circumferential direction, and the apertures of the through hole I, the through hole II, the through hole III, the through hole IV and the through hole V are all the same;
the third through hole is positioned at the midpoint of the first through hole and the fifth through hole;
when the outer diameter d of the pipe body is less than or equal to 10mm, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 0.4mm; when d is more than 10 and less than or equal to 20, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 0.6mm; when d is more than 20 and less than or equal to 30, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 0.8mm; when d is more than 30 and less than or equal to 40, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 1.0mm; and when d is more than 40 and less than or equal to 50, the apertures of the first through hole, the second through hole, the third through hole, the fourth through hole and the fifth through hole are 1.2mm.
2. The sensitivity calibration coupon for simultaneous detection of defects of a tube bundle of a non-ferromagnetic heat exchanger by far-field eddy currents and acoustic pulses according to claim 1, wherein: the axial distance between the second through hole and the third through hole is 50mm.
3. The sensitivity calibration coupon for simultaneous detection of defects of a tube bundle of a non-ferromagnetic heat exchanger by far-field eddy currents and acoustic pulses according to claim 1, wherein: the axial distance between the through holes IV and III is 50mm.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910687098.5A CN110308210B (en) | 2019-07-26 | 2019-07-26 | Sensitivity calibration sample tube for detecting tube bundle defects of nonferromagnetic heat exchanger by far-field eddy current and acoustic pulse |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910687098.5A CN110308210B (en) | 2019-07-26 | 2019-07-26 | Sensitivity calibration sample tube for detecting tube bundle defects of nonferromagnetic heat exchanger by far-field eddy current and acoustic pulse |
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| Publication Number | Publication Date |
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| CN110308210A CN110308210A (en) | 2019-10-08 |
| CN110308210B true CN110308210B (en) | 2024-04-09 |
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| CN108152367A (en) * | 2018-01-11 | 2018-06-12 | 中国大唐集团科学技术研究院有限公司华中分公司 | A kind of low frequency array is vortexed positioning and quantitative analysis method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2270420B1 (en) * | 2009-06-30 | 2014-11-12 | Services Pétroliers Schlumberger | Method and apparatus for removal of the double indication of defects in remote eddy current inspection of pipes |
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- 2019-07-26 CN CN201910687098.5A patent/CN110308210B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000227420A (en) * | 1999-02-04 | 2000-08-15 | Nkk Corp | Multi-probe type eddy current examination and eddy current test equipment |
| CN101458229A (en) * | 2008-12-31 | 2009-06-17 | 东北轻合金有限责任公司 | Phi 20mm-phi 38mm aluminum alloy thin walled pipe eddy current inspection method |
| CN204008560U (en) * | 2014-07-22 | 2014-12-10 | 华中科技大学 | Defect inspection sensor and device based on electromagnetic acoustic longitudinal wave guide |
| CN105181791A (en) * | 2015-09-30 | 2015-12-23 | 西安交通大学 | Pulsed eddy current and electromagnetic ultrasonic composite based nondestructive body defect testing method |
| CN107941905A (en) * | 2018-01-11 | 2018-04-20 | 中国大唐集团科学技术研究院有限公司华中分公司 | A kind of low frequency array eddy current testing device and steel pipe inner wall corrosion default detection method |
| CN108152367A (en) * | 2018-01-11 | 2018-06-12 | 中国大唐集团科学技术研究院有限公司华中分公司 | A kind of low frequency array is vortexed positioning and quantitative analysis method |
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