CN102495129A - Adjustable magnetic pumping array detecting method for metal damage and adjustable magnetic actuated array detecting device for same - Google Patents
Adjustable magnetic pumping array detecting method for metal damage and adjustable magnetic actuated array detecting device for same Download PDFInfo
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- CN102495129A CN102495129A CN2011103743981A CN201110374398A CN102495129A CN 102495129 A CN102495129 A CN 102495129A CN 2011103743981 A CN2011103743981 A CN 2011103743981A CN 201110374398 A CN201110374398 A CN 201110374398A CN 102495129 A CN102495129 A CN 102495129A
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Abstract
The invention relates to a method and a device for rapidly, qualitatively and quantitatively testing and evaluating defects such as cracks, corrosion pits and the like of metal materials, which belong to the technical field of electromagnetic non-destructive testing for metal damage. The method uses an array receiving coil as a feedback element to test the magnetization state of the surface of a tested piece, and the exciting current of an exciting coil is adjusted according to testing results, so that the magnetization condition of a magnetic field of is improved, and flaw detection sensitivity of the tested piece in different directions is enhanced. By means of designing the orthogonal exciting magnetic field on the device, the amplitude and the direction of the exciting magnetic field can be changed. Compared with a traditional magnetic actuated mode, the method has the advantages that defect omission ratio can be reduced to a great degree, reliability of test results is improved, and the method has high practical application value for electromagnetic non-destructive testing of tested pieces in complicated shapes.
Description
Technical field
The present invention relates to fast qualitative, detection by quantitative assessment method and the device of defectives such as a kind of metal material crackle, etch pit, belong to the electromagnetic nondestructive testing field of damaged metal.
Background technology
The crackle of hardware and corrosion default etc. be extensively exist influence the commercial unit damaged metal form in tired and serviceable life; Carry out detection and assessment to such damaged metal; For the safe operation of the equipment of assurance, prolong the serviceable life of equipment, have significant values and meaning.
The magnetic field detection method is the alternating magnetic field that in metal material, applies certain frequency, can induce the uniform alternate electric current in the metal surface owing to kelvin effect, and the external space produces alternating magnetic field in the metal surface; If there are defectives such as crackle in the metal surface, because the variation of resistivity certainly will exert an influence to distribution of current; The electric current line can produce deflection near defective; Can distort in the magnetic field of surface of the work, through measuring the variation in this magnetic field, just can confirm the length and the degree of depth of defectives such as crackle.
The known method of utilizing alternating magnetic field to detect metal defect is utilized amplitude and the constant magnetic field excitation source of direction mostly; In some patents (like " based on the quadrature double-U-type intelligent visual detection array of ACFM " application number: CN 101706474A; Patent " ACFM intelligent visual defect detection system " application number: CN101701934A), propose and realized the generation device in the rotatable magnetic field of a kind of quadrature, have remarkable effect for the detection sensitivity that improves the stochastic distribution crackle on the actual testee; Yet the variation of mainly having studied magnetic direction in the above-mentioned patent is not mentioned for the sensitivity that detects the stochastic distribution crackle for the variation of field strength values for the effect that improves detection sensitivity.
Utilize alternating magnetic field to detect the sensitivity of defective, outside the Pass having, also relevant with the uniformity coefficient of the size of magnetic field intensity and Distribution of Magnetic Field with magnetic direction; Because the difference of alternating magnetic field intensity can be brought very mistake to testing result; And the shape of actual measured piece is irregular, if the variation of magnetic field intensity is not considered in magnetic field in the process of rotation excitation, is easy to because of magnetic field distribution inhomogeneously, and the magnetization effect that makes defective is influenced and influence detects effect.
Therefore on aforementioned working foundation, design the change excitation field that a kind of magnetic direction changes, the amplitude power can be regulated, and proposed to utilize this exciting field and array-type sensor to detect the lossless detection method of damaged metal.
Summary of the invention
The objective of the invention is to utilize the ultimate principle of magnetic field detection method, design a kind of Non-Destructive Testing and assessment method and device of damaged metal, can change fast, thereby technical feasibility is provided for detecting the test specimen damage quickly and easily to test specimen.
The present invention realizes through following technical scheme.
Excitation field adopted DOM in time even variation, amplitude can magnetize the variable magnetic field energisation mode that effect is regulated according to reality, to guarantee that the defective of actual conditions lower edge all directions stochastic distribution is had enough detection sensitivities; The excitation field that the variation of magnetic direction is spent through employing two-way phase phasic difference 90 synthesizes realizes that the adjusting of magnetic field amplitude realizes through the array magnetic test coil.The array magnetic test coil is used to detect the damaged metal on the test specimen, variation that simultaneously also can the induced magnetization field strength.When magnetic test coil is positioned at defect area, the general transition that exists by a relatively large margin of output signal amplitude; When magnetic test coil was in non-defect area, the amplitude difference of output signal had just reflected the difference of magnetizing field strength.According to the power of magnetic test coil signal amplitude, just can regulate the magnetization current of drive coil, thereby make the magnetizing field on the test specimen adjusted, make the magnetization effect as far as possible evenly, improve detection sensitivity to the diverse location defective.Concrete implementation method is following:
Be example with 3 * 3 array-type sensors shown in Fig. 1, as shown in Figure 2.At first in the reading of adjacent windings, get difference according to horizontal and vertical order:
Laterally, u
12=u
1-u
2u
23=u
2-u
3
u
45＝u
4-u
5；u
56＝u
5-u
6；
u
78＝u
7-u
8；u
89＝u
8-u
9；
Vertically, u
14=u
1-u
4u
47=u
4-u
7
u
25＝u
2-u
5；u
58＝u
5-u
8；
u
36＝u
3-u
6；u
69＝u
6-u
9
Set defective discrimination threshold M, the inhomogeneous discrimination threshold m in magnetic field
(1) if certain value thinks then that greater than M this result is caused by defective among the aforementioned calculation result, do not cause by magnetizing field is inhomogeneous; This moment, the function of array coil was to detect defective, and excitation field need not regulated, and directly the result is differentiated in output;
(2) if the aforementioned calculation result less than M, then does following processing:
Laterally:
Vertically:
If u
h＞m shows that then the cross magnetization uniformity coefficient needs adjustment, increases the transverse coil exciting current this moment, strengthens the cross magnetization field strength, improves cross magnetization field effect;
If u
z＞m shows that then the longitudinal magnetization uniformity coefficient needs adjustment, increases the longitudinal coil exciting current this moment, strengthens the longitudinal magnetization field strength, improves longitudinal magnetization field effect;
If u
h, u
zAll, show that then present magnetizing field is respond well, need not adjust less than m.
, as feedback element the magnetizing field strength on the test specimen as feedback signal, is in time regulated the magnetization effect of exciting field with the array detecting element, guaranteed that magnetic field is evenly approximate on all directions.Detection system adopts the array architecture mode, has substituted traditional scanning detection mode, thereby has increased substantially detection speed.
Basic skills of the present invention mainly be adopted amplitude and direction can self-regulating excitation magnetizing field and the array receiving coil realize the detection of damaged metal.Because the direction and the position distribution of damaged metal such as crackle have randomness under the actual condition; And the changeless magnetization exciting field of amplitude and direction only has magnetization preferably to the defective that distributes along certain direction; And the magnetization effect is also relevant with the position that damage occurs, and so just possibly produce omission to some damage that is in insensitive orientation.It is vertical each other to have designed a kind of direction in this patent, phase phasic difference 90 degree, and amplitude can be according to the two-dimentional alternating magnetic field of magnetizing field situation real-time regulated.This two-dimensional magnetic field has synthesized the ellipticity magnetizing field of an amplitude and direction-agile on test specimen, so just can strengthen the magnetic field distribution in the weak orientation of magnetization effect according to the test specimen features of shape, improves detection sensitivity; Because magnetizing field direction and intensity change in time, effectively reduce the magnetization blind area of defective simultaneously, reduced loss.
Said method realizes that by the pick-up unit that is designed this device is as shown in Figure 1, is made up of two-dimentional excitation field, array receiving element, test specimen and base plate.The two dimension excitation field is made up of signal excitation circuit, drive coil, yoke, pole shoe etc.; The signal excitation circuit is as shown in Figure 3, is made up of sine wave generating circuit, feedback element, programmable amplifier, phase shifter and power amplifier; The sine-wave oscillation signal is divided into two-way, and wherein one the tunnel through forming phase quadrature with another road behind the phase shifter, and the magnetizing field direction is changed in time; The adjusting of magnetization current amplitude is through the receiving element of array architecture on the test specimen; Magnetic field state is passed to computing machine through after the A/D sampling; Computing machine is differentiated uniformity of magnetic field through algorithm, changes exciting current according to the result through programmable amplifier, constitutes the adjustable mode of magnetic pumping current amplitude; Just can be according to the magnetic field distribution situation; The excitation field amplitude is regulated, thereby effectively strengthen excitation effect, make that the defective in each orientation all can be detected with higher sensitivity on the test specimen weak orientation, magnetic field.Test specimen is placed on the rigid frame of four pole shoes compositions during detection, and framework plays the effect of a location; Test specimen and the drive coil, the device base plate that are placed on the pole shoe have constituted a closed magnetic circuit, and drive coil can produce amplitude and direction all in the gradient magnetic field that changes through this magnetic circuit on test specimen, thereby realization is to the magnetization of each position defective on the test specimen.The quantity of array-type sensor requires to decide according to actual detected with the neighbor distance of each sensor; In order to guarantee not omission of flaw indication; The effective range that should guarantee the array detection coil has certain overlapping region; Thereby the defect information that produces is redundant and stack, can adopt blind source to separate scheduling algorithm and differentiate strategy to solve.
Beneficial effect
The present invention through adopt direction to change in time, amplitude is fed back according to magnetic field state and self-regulating variable magnetic excitation field as detecting driving source; Utilize the array solenoid as receiving element; Can realize effective detection, compare, can reduce the defective loss largely with traditional magnetic pumping mode to each orientation damaged metal on the test specimen; Improve the testing result reliability, have stronger actual application value for the electromagnetic nondestructive of the more complicated test specimen of shape.
Description of drawings
Below in conjunction with accompanying drawing and embodiment the present invention is further specified:
Fig. 1 damaged metal adjustable magnetic fields pick-up unit.
Fig. 2 sensor array position view.
Fig. 3 two-dimensional magnetic field signal excitation circuit.
Embodiment
For enforcement and the advantage that this patent is described better, this patent is done further explanation below in conjunction with concrete embodiment.
Test specimen selects for use mild carbon steel Q235 steel commonly used to process long 100mm, wide 40mm, thick 3mm.
Receiving coil in the present embodiment adopts line directly for the enameled wire coiling of 0.06mm forms, and internal coil diameter is 2mm, and external diameter is 4mm, and the coil effective length is 2mm, and coil turn is 500.The coil rack maximum outside diameter is 5mm, highly is 5mm.
Excitation unit in the present embodiment is distributed in laterally and vertical two vertical direction.Two identical field coils are respectively arranged on each direction.Coil employing line directly is 0.6 enameled wire coiling, and internal coil diameter is 32mm, and the coil effective length is 24mm, and coil turn is 250 circles.
Be aided with the sine generation circuit of UA741CP integrated chip and be that the power amplification circuit of core is that present embodiment provides field power supply with TDA2030 with RC, the power supply peak value is 6.8V.
Implementation process: at first according to the various piece in the step joint detection system, and the fixed array probe.The power supply of enabling signal receiving circuit and subsequent process circuit; Start the power supply of excitation unit, regulate the feedback resistance in the sine wave generating circuit, make the circuit starting of oscillation, and waveform requires well undistorted.Even for the magnetic field that guarantees the test specimen surface, adopt the array receiving coil as feedback element, to regulate the magnetic field intensity of test specimen surface at horizontal, vertical both direction.Through the acquisition software of control industrial computer, but the test specimen status information of array formula probe institute overlay area is gathered, is handled and judges.Testing result under single direction excitation field and the scalable excitation field is contrasted.Test shows, adopts the excitation field detection method of array element as feedback regulation, can effectively detect each position defective on the test specimen, has improved magnetic field homogeneity, has improved detection sensitivity.
The test specimen that present embodiment is merely a kind of material detects.The present invention can detect multiple ferrimagnet result, and the number, spacing of probe flexible arrangement as required.Everyly do not break away from the equivalence of accomplishing under the disclosed spirit of the present invention or revise, all be contained in the scope of the present invention's protection.
Claims (2)
1. scalable exciting field array detection method that is applicable to the damage of metal material electromagnetic nondestructive comprises can changing magnetization current amplitude and direction and the magnetic field excitation mode that changes, thereby realizes the high-sensitivity detecting method of different azimuth damaged metal; And utilize the array detecting element, thereby the method for realization magnetic field uniform magnetization effect etc. as magnetic field detection and feedback element; It is characterized in that:
(1) adopted detection defective measurement and the signal feedback element of array coil as the magnetizes effect; Utilize relatively in time the magnetization effect of test specimen being adjusted of testing result and driving voltage, to guarantee on test specimen, obtaining magnetizing field comparatively uniformly;
(2) proposed a kind of self-adaptation method of discrimination that magnetic field is regulated that carries out, through defective discrimination threshold and magnetic field uniformization threshold value are set, can effectively distinguish the information that detecting element extracts, thereby realize the differentiation of defective and the adjusting in magnetic field.
2. the adjustable magnetic fields array detection device with feedback and adaptation function according to claim 1 is characterized in that:
(1) arrayed elements has defects detection simultaneously and is used for information measurement and the feedback function that magnetic field is regulated;
(2) adopt a kind of symmetrical expression magnetization configuration, this structure is made up of magnetic pole base plate, four field coils and frame-type pole shoe, and the frame-type pole shoe has the fixedly effect of test specimen again, and the while can be changed test specimen quickly and easily;
(3) adopt the array test coil as feedback element, through sample circuit with relatively differentiate algorithm, control programmable amplifier multiple is regulated the magnetic field excitation electric current, the adjusting of realization magnetic excitation field.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102841136A (en) * | 2012-09-01 | 2012-12-26 | 爱德森（厦门）电子有限公司 | Variable-array eddy current scanning rules based on array element coils |
| CN104198576A (en) * | 2014-09-11 | 2014-12-10 | 北京理工大学 | Device for rapidly detecting inner crack of metal bent component |
| CN104880508A (en) * | 2015-04-13 | 2015-09-02 | 北京理工大学 | Orthogonal rotation exciting field eddy current transducer |
| CN108459072A (en) * | 2018-04-17 | 2018-08-28 | 东莞市慧眼数字技术有限公司 | A kind of damaged metal remote detection terminal based on electromagnetic conductive |
| CN111879849A (en) * | 2020-07-16 | 2020-11-03 | 南昌航空大学 | Symmetrical non-directional eddy current detection sensor and detection method |
| CN112147215A (en) * | 2020-09-23 | 2020-12-29 | 上海磁海无损检测设备制造有限公司 | Magnetization control method and system, control device and equipment for magnetic powder flaw detection |
| JP2021519426A (en) * | 2018-03-27 | 2021-08-10 | イリノイ トゥール ワークス インコーポレイティド | Magnetic inspection device using true Gaussian magnetic measurement |
| CN113390954A (en) * | 2021-07-08 | 2021-09-14 | 中国石油大学(华东) | Underwater structure crack propagation visual monitoring system based on alternating-current electromagnetic field |
| CN113640370A (en) * | 2021-08-09 | 2021-11-12 | 中国石油大学(北京) | Pipeline magnetic flux leakage detector capable of realizing variable-direction excitation |
| WO2023280023A1 (en) * | 2021-07-08 | 2023-01-12 | 中国石油大学(华东) | Underwater structure crack propagation visual monitoring system based on alternating-current electromagnetic field, and alternating-current electromagnetic field crack visual monitoring and evaluation method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5434506A (en) * | 1992-11-09 | 1995-07-18 | The Babcock & Wilcox Company | Eddy current inspection with stationary magnetic fields and scanning sensor arrays |
| CN1186549A (en) * | 1995-06-07 | 1998-07-01 | 巴依奥桑斯股份有限公司 | Magnetic location system with adapative feedback control |
| CA2357233A1 (en) * | 2000-09-12 | 2002-03-12 | Her Majesty The Queen In Right Of Canada, As Represented By The Minister Of Natural Resources Canada | Sensor head for acfm based crack detection |
| GB2411741A (en) * | 2004-03-03 | 2005-09-07 | Ims Nanofabrication Gmbh | Compensation of magnetic fields |
| CN101701934A (en) * | 2009-11-16 | 2010-05-05 | 中国石油大学(华东) | ACFM intelligent visual defect detection system |
| CN101706474A (en) * | 2009-11-16 | 2010-05-12 | 中国石油大学(华东) | Orthorhombic double-U-type intelligent visual detection array probe based on alternating current field measurement (ACFM) |
-
2011
- 2011-11-23 CN CN2011103743981A patent/CN102495129A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5434506A (en) * | 1992-11-09 | 1995-07-18 | The Babcock & Wilcox Company | Eddy current inspection with stationary magnetic fields and scanning sensor arrays |
| CN1186549A (en) * | 1995-06-07 | 1998-07-01 | 巴依奥桑斯股份有限公司 | Magnetic location system with adapative feedback control |
| CA2357233A1 (en) * | 2000-09-12 | 2002-03-12 | Her Majesty The Queen In Right Of Canada, As Represented By The Minister Of Natural Resources Canada | Sensor head for acfm based crack detection |
| GB2411741A (en) * | 2004-03-03 | 2005-09-07 | Ims Nanofabrication Gmbh | Compensation of magnetic fields |
| CN101701934A (en) * | 2009-11-16 | 2010-05-05 | 中国石油大学(华东) | ACFM intelligent visual defect detection system |
| CN101706474A (en) * | 2009-11-16 | 2010-05-12 | 中国石油大学(华东) | Orthorhombic double-U-type intelligent visual detection array probe based on alternating current field measurement (ACFM) |
Non-Patent Citations (5)
| Title |
|---|
| GUO-MING C 等: "Structural optimization of 2-D array probe for alternating current field measurement", 《NDT & E INTERNATIONAL》 * |
| ZHOU J ET AL.: "A non-uniform model for alternating current field measurement of fatigue cracks in metals", 《INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS》 * |
| 丁天怀: "电涡流传感器阵列测试技术", 《测试技术学报》 * |
| 康中尉 等: "交变磁场测量数学模型及类匀强场的建立", 《无损检测》 * |
| 李伟 等: "基于双U形激励的交流电磁场检测缺陷可视化技术", 《机械工程学报》 * |
Cited By (13)
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|---|---|---|---|---|
| CN102841136B (en) * | 2012-09-01 | 2015-07-29 | 爱德森（厦门）电子有限公司 | A kind of the change in formation row eddy-current instrument method for designing based on array element coil |
| CN102841136A (en) * | 2012-09-01 | 2012-12-26 | 爱德森（厦门）电子有限公司 | Variable-array eddy current scanning rules based on array element coils |
| CN104198576A (en) * | 2014-09-11 | 2014-12-10 | 北京理工大学 | Device for rapidly detecting inner crack of metal bent component |
| CN104880508A (en) * | 2015-04-13 | 2015-09-02 | 北京理工大学 | Orthogonal rotation exciting field eddy current transducer |
| JP7431170B2 (en) | 2018-03-27 | 2024-02-14 | イリノイ トゥール ワークス インコーポレイティド | Magnetic inspection equipment using true Gaussian magnetic measurements |
| JP2021519426A (en) * | 2018-03-27 | 2021-08-10 | イリノイ トゥール ワークス インコーポレイティド | Magnetic inspection device using true Gaussian magnetic measurement |
| CN108459072A (en) * | 2018-04-17 | 2018-08-28 | 东莞市慧眼数字技术有限公司 | A kind of damaged metal remote detection terminal based on electromagnetic conductive |
| CN108459072B (en) * | 2018-04-17 | 2024-05-28 | 东莞市慧眼数字技术有限公司 | Metal damage remote detection terminal based on electromagnetic conduction |
| CN111879849A (en) * | 2020-07-16 | 2020-11-03 | 南昌航空大学 | Symmetrical non-directional eddy current detection sensor and detection method |
| CN112147215A (en) * | 2020-09-23 | 2020-12-29 | 上海磁海无损检测设备制造有限公司 | Magnetization control method and system, control device and equipment for magnetic powder flaw detection |
| WO2023280023A1 (en) * | 2021-07-08 | 2023-01-12 | 中国石油大学(华东) | Underwater structure crack propagation visual monitoring system based on alternating-current electromagnetic field, and alternating-current electromagnetic field crack visual monitoring and evaluation method |
| CN113390954A (en) * | 2021-07-08 | 2021-09-14 | 中国石油大学(华东) | Underwater structure crack propagation visual monitoring system based on alternating-current electromagnetic field |
| CN113640370A (en) * | 2021-08-09 | 2021-11-12 | 中国石油大学(北京) | Pipeline magnetic flux leakage detector capable of realizing variable-direction excitation |
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Application publication date: 20120613 |