CN110230976A - A kind of method of non-destructive testing rail rolling contact fatigue crack propagation vertical depth - Google Patents
A kind of method of non-destructive testing rail rolling contact fatigue crack propagation vertical depth Download PDFInfo
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- CN110230976A CN110230976A CN201910398548.9A CN201910398548A CN110230976A CN 110230976 A CN110230976 A CN 110230976A CN 201910398548 A CN201910398548 A CN 201910398548A CN 110230976 A CN110230976 A CN 110230976A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/26—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring depth
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
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Abstract
The invention discloses a kind of methods of non-destructive testing rail rolling contact fatigue crack propagation vertical depth.This method is able to solve in rail maintenance bruting process by virtue of experience or assumes the problem of judging crackle vertical depth, provides quantitative theory analysis for railway system's rail maintenance, extends rail service life, reduce railway operation maintenance cost.This method is based on existing ac magnetic field measuring technique, measuring probe needs to be scanned crackle in 45 ° of angles with crack surfaces length direction, and cross crack surfaces lengthwise centers point, obtain Bz signal, Bz trough peak ratio is calculated, the ratio and actual crack vertical angle relationship are studied, the vertical depth of crackle is calculated in the crackle pocket depth provided in conjunction with Bx signal.It solves to obtain the crackle of different surfaces and vertical angle using finite element model and Bz trough peak ratio relationship and establishes database, input crack surfaces length, Bz trough crest ratio, the vertical depth of exportable crackle.
Description
Technical field
The present invention relates to nondestructive inspections and field of track traffic, and in particular to a kind of electromagnetism nondestructive characterisation (NDC) rail is in rolling contact
The method of crack Propagation vertical depth.
Background technique
Rolling contact fatigue crackle is one of rail and the typical surface defect of wheel, constantly duplicate with wheel by rail
Transverse direction and longitudinal traction cause.Rolling contact fatigue crackle is usually to be in 10-30 ° of angle (vertical angle with horizontal direction
Degree) to rail internal extended (attached drawing 1), when crack propagation reaches fatigue limit, crackle can be with biggish vertical angle to steel
It is rapidly extended inside rail, causes the fracture of rail, the accident that easily causes that the train was derailed.For the angle of rail maintenance, need
It periodically polishes rail, elimination is ground before crackle reaches capacity depth.The precondition of steel rail grinding is to need
It is to be understood that vertical expansion depth of the crackle inside rail, could formulate to scientific quantitative analysis corresponding grinding depth and maintenance week
Phase.In the application of practical steel rail grinding, the vertical depth of crackle is often according to assuming to calculate known to vertical angle, either
It is compared with standard crack signal to judge.Since rolling contact fatigue crack shape there are random scrambling and is mostly
The arrangement of crackle cluster needs to carry out the algorithm of crackle dimensional measurement empirical amendment, and maintenance cost is high, and rail grinds depth not
Accurately.If degree of grinding is lighter, crackle be cannot be completely eliminated, and crackle is caused to continue that it is disconnected to cause rail to rail internal extended
It splits；If degree of grinding is larger, rail material loss is more, shortens the service life of rail, increases railway operation cost.
Ac magnetic field mensuration is the electromagnetic nondestructive testing based on alternating current skin effect, in the world,
This method is to be widely used in deep sea drilling platform, petroleum pipeline, and the electromagnetism of the metal component surfaces defects detection such as rail is lossless
One of detection technique.Compared to other non-destructive testing technologies, ac magnetic field mensuration has contactless, high temperature resistant, corrosion resistant
The features such as erosion, efficient quick, equipment is small and exquisite, economical and practical.Under normal circumstances ac magnetic field measuring probe along crackle table
Face length is scanned, so that the uniform AC field perpendicular to crack length direction is introduced in metal surface, crack defect
In the presence of being uniformly distributed for electric field can be upset, electric current is forced to flow to crackle both ends and crack surface, while probe is detected by this
Electric field causes the variation in magnetic field to judge the presence and size of crackle.Due to electric current along crack surface flow, cause across
The magnetic field strength of crackle reduces, so that trough occurs in ac magnetic field mensuration Bx signal；Pass through the changes of magnetic field (Bx in the direction x
Signal) expansion depth of crackle can be measured, both pocket depth, was shown in attached drawing 1, attached drawing 2.Electric current is clockwise and passes counterclockwise through
Crackle both ends cause magnetic field in the fluctuation in the direction z, one positive one negative Distribution of Magnetic Field are formed, so that ac magnetic field mensuration Bz
There is wave crest and trough in signal；The length surface of crackle, attached drawing 2 can be measured by the distance of Bz signal wave crest trough.
Existing ac magnetic field measurement method can only detect the length surface and pocket depth of crackle, and for iron
For the maintenance of road, it is vertical there is an urgent need to the measurement parameter known that rail, which needs periodically polishing to eliminate rolling contact fatigue crackle,
Expansion depth, attached drawing 1.The present invention is based on existing ac magnetic field measuring techniques to propose measurement crackle in conjunction with finite element modelling
The method of vertical angle provides quantitative to calculate the vertical depth of crackle in conjunction with the pocket depth of crackle for steel rail grinding
Analysis improves rail maintenance system, extends rail life cycle, improves railway safety in utilization.
Summary of the invention
It is an object of the invention to utilize ac magnetic field mensuration non-destructive testing rail rolling contact fatigue crack size,
Vertical depth of the crackle to rail internal extended is calculated by signal analysis method disclosed in this patent, is railway periodic maintenance
(steel rail grinding) provides quantitative analysis basis, ensures that railway uses safe, extension rail life cycle.It is surveyed using ac magnetic field
Amount probe obtains ac magnetic field mensuration Bz signal to be scanned in 45 ° of angle directions to crackle with crack surfaces length.
Due to the relationship of crackle vertical angle, Distribution of Magnetic Field can be caused to cause the trough of Bz signal, wave relative to the offset of crack position
Peak value is asymmetric, therefore proposes Bz signal trough crest ratio measurement parameter, studies the parameter and actual crack vertical angle relationship,
Attached drawing 2；The emulation finite element model of alternating electromagnetic field measurement rolling contact fatigue crackle is established, and is tested by actual measured results
Model of a syndrome correctness；Bz signal trough crest ratio-crackle vertical angle under different crack lengths is established using finite element model,
Establish database.According to actual crack measurement result, crackle vertical angle is determined by database, in conjunction with crackle pocket depth,
It calculates and determines that crack propagation vertical depth, method flow are shown in attached drawing 3.
The specific real time steps of the method for the present invention are as follows:
1. ac magnetic field measuring probe is scanned along crack surfaces length, Bx and Bz signal is obtained, determines crackle
Pocket depth and length surface.
2. ac magnetic field measuring probe is to be scanned crackle in 45 ° of angle directions with crack surfaces length, and mistake
Crack surfaces lengthwise centers point, obtains Bz signal, calculates to obtain Bz trough crest ratio.
3. alternating electromagnetic field measurement rolling contact fatigue crackle emulation finite element model is established according to actual measurement principle,
Solution obtains analog signal, and is verified with actual measured results, determines the correctness of model.
4. obtaining vertical angle (0-90 °) and Bz under crackle different surfaces length (3-40mm) using finite element model solution
Trough peak ratio relationship establishes database in case actual measured results analysis is used.
5. inputting the crack surfaces length that actual measurement obtains in database, Bz trough crest ratio exports the vertical of crackle
Depth.
6. combining the pocket depth of crackle, hanging down for crackle is calculated using trigonometric function in the crackle vertical angle of output
Straight depth
The utility model has the advantages that the present invention is directed to propose a kind of non-destructive testing rail rolling contact fatigue crack propagation vertical depth
Method, this method is based on existing ac magnetic field measuring technique, is simple and efficient, facilitates operation, by improved measurement method,
It proposes Bz signal trough peak ratio concept, accurately calculates the vertical expansion depth of crackle.The finite element model that this method is established
And database illustrative simplicity, it is easy to operate, it can be updated and be expanded according to actual crack situation, can repeated quickly once being set up
It uses.The crack propagation vertical depth being calculated by this method provides theoretical quantitative analysis for railway system's rail maintenance,
It determines the regular grinding depth aim parameter of rail, accomplishes to shoot the arrow at the target, replace existing empirical judgement, greatly extending rail makes
With the service life, railway operation maintenance cost is reduced, while preferably guaranteeing safety of railway traffic, people's property safety is played pre-
Anti- property protective effect.The method of the present invention is not limited to the detection of steel rolling contact fatigue crackle, while being suitable for metal material table
The characterization of the non-perpendicular running crack in face, such as stress corrosion cracking (SCC), gear root crack etc..
Detailed description of the invention
Fig. 1 is rolling contact fatigue crackle to rail internal extended schematic diagram.
Fig. 2 is electric current, Distribution of Magnetic Field and probe measurement path schematic diagram around crackle.
Fig. 3 is that rolling contact fatigue crackle vertical depth determines flow chart.
Fig. 4 is single crack finite element modelling and the Bz trough peak ratio comparison of actual measurement.
Specific embodiment
Embodiment 1
In laboratory conditions, the single crack with different vertical depth is made on rail using electrical discharge machining,
And alternating electromagnetic field measurement is carried out according to step 1 and 2 to crackle and obtains Bx, Bz signal calculates crackle pocket depth, length surface
And Bz trough peak ratio.Crackle pocket depth is inputted in the finite element data library that step 3 and step 4 are established, surface is long
Degree and Bz trough peak ratio, obtain crackle vertical angle, crackle vertical depth are calculated using trigonometric function.Finite element
Attached drawing 4 is shown in the comparison of the Bz trough peak ratio of simulation and actual measurement.
Embodiment 2
This application example and example 1 are the difference is that test object is the rolling contact fatigue crackle in practical rail
Cluster (is generally made of a plurality of crackle, spacing 1-20mm or so).Crackle cluster information database similarly is established using finite element model,
And judgement is measured to crackle longest vertical depth in crackle cluster, thoroughly to remove crackle.Ac magnetic field measuring probe
To be in the scanned Crack Center point in 45 ° of directions with crack surfaces length, Bz trough peak ratio is obtained, database is entered data into
Crackle vertical angle, and binding pocket depth is calculated, calculates crackle maximum perpendicular depth.Calculated result and actual result pair
Than as shown in the table:
The application the method for the present invention of table 1 calculates crackle vertical depth and actual comparison
Claims (1)
1. a kind of method of non-destructive testing rail rolling contact fatigue crack propagation vertical depth, which is characterized in that this method packet
Include following steps:
(1) ac magnetic field measuring probe is scanned along crack surfaces length, is obtained Bx and Bz signal, is determined the pocket of crackle
Depth and length surface；
(2) ac magnetic field measuring probe is to be scanned crackle in 45 ° of angle directions with crack surfaces length, and crosses crackle
Length surface central point obtains Bz signal, calculates to obtain Bz trough crest ratio；
(3) according to actual measurement principle, alternating electromagnetic field measurement rolling contact fatigue crackle emulation finite element model is established, is solved
Analog signal is obtained, and is verified with actual measured results, determines the correctness of model；
(4) vertical angle (0-90 °) and Bz wave under crackle different surfaces length (3-40mm) are obtained using finite element model solution
Paddy peak ratio relationship establishes database in case actual measured results analysis is used；
(5) the crack surfaces length that actual measurement obtains is inputted in database, Bz trough crest ratio exports the vertical depth of crackle
Degree；
(6) pocket depth of crackle is combined, the vertical depth of crackle is calculated using trigonometric function for the crackle vertical angle of output
Degree.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110926942A (en) * | 2019-11-19 | 2020-03-27 | 西安理工大学 | Numerical analysis method for rolling contact fatigue cracks of rails in ABAQUS |
| CN111855448A (en) * | 2020-07-31 | 2020-10-30 | 东风商用车有限公司 | Metal material rolling contact fatigue test crack detection method |
| CN112857197A (en) * | 2021-04-09 | 2021-05-28 | 中国石油大学(华东) | Rotating electromagnetic field non-ferromagnetic material crack size measurement method |
| CN113030187A (en) * | 2021-03-05 | 2021-06-25 | 桂林理工大学 | Method for representing three-dimensional size of steel rail rolling contact fatigue crack cluster in electromagnetic nondestructive mode |
| CN113390955A (en) * | 2021-07-08 | 2021-09-14 | 中国石油大学(华东) | Visual monitoring and evaluation method for cracks of alternating current magnetic field |
| CN113433060A (en) * | 2021-06-23 | 2021-09-24 | 马鞍山钢铁股份有限公司 | Method for evaluating rolling contact fatigue performance of railway locomotive wheel surface |
| CN114543656A (en) * | 2022-03-07 | 2022-05-27 | 桂林理工大学 | Method for reconstructing rail complex asymmetric surface crack propagation shape based on alternating current electromagnetic field |
| 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 (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1050091A (en) * | 1989-09-05 | 1991-03-20 | 西屋电气公司 | Magnetic particle inspection field strength indicator |
| JP2005121506A (en) * | 2003-10-17 | 2005-05-12 | Shinko Inspection & Service Co Ltd | Eddy current test equipment |
| CN101109728A (en) * | 2007-08-17 | 2008-01-23 | 中国人民解放军装甲兵工程学院 | Method for monitoring ferromagnetic material fatigue crack expansion by variated magnetic signal |
| CN102954999A (en) * | 2011-08-19 | 2013-03-06 | 中国石油天然气股份有限公司 | Triaxial magnetic leakage inner detection line signal determination method for girth joint crack defects of pipeline |
| CN103033557A (en) * | 2011-09-29 | 2013-04-10 | Abb技术有限公司 | Method and arrangement for crack detection in a metallic material |
| CN203572806U (en) * | 2013-09-30 | 2014-04-30 | 天津工程机械研究院 | On-line fatigue crack detection system |
| CN105486745A (en) * | 2015-12-10 | 2016-04-13 | 中国石油大学(华东) | Defect signal high-precision space imaging system and method based on alternating-current electromagnetic field |
| CN109060942A (en) * | 2018-08-31 | 2018-12-21 | 南京航空航天大学 | Steel rail defect depth detection method based on leakage magnetic detection device |
| CN109060944A (en) * | 2018-08-31 | 2018-12-21 | 南京航空航天大学 | Steel rail defect depth detection method based on leakage magnetic detection device and neural network |
| CN109737899A (en) * | 2019-01-25 | 2019-05-10 | 北京科技大学 | A kind of metal material crack-type defect depth measurement device and method |
-
2019
- 2019-05-14 CN CN201910398548.9A patent/CN110230976B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1050091A (en) * | 1989-09-05 | 1991-03-20 | 西屋电气公司 | Magnetic particle inspection field strength indicator |
| JP2005121506A (en) * | 2003-10-17 | 2005-05-12 | Shinko Inspection & Service Co Ltd | Eddy current test equipment |
| CN101109728A (en) * | 2007-08-17 | 2008-01-23 | 中国人民解放军装甲兵工程学院 | Method for monitoring ferromagnetic material fatigue crack expansion by variated magnetic signal |
| CN102954999A (en) * | 2011-08-19 | 2013-03-06 | 中国石油天然气股份有限公司 | Triaxial magnetic leakage inner detection line signal determination method for girth joint crack defects of pipeline |
| CN103033557A (en) * | 2011-09-29 | 2013-04-10 | Abb技术有限公司 | Method and arrangement for crack detection in a metallic material |
| CN203572806U (en) * | 2013-09-30 | 2014-04-30 | 天津工程机械研究院 | On-line fatigue crack detection system |
| CN105486745A (en) * | 2015-12-10 | 2016-04-13 | 中国石油大学(华东) | Defect signal high-precision space imaging system and method based on alternating-current electromagnetic field |
| CN109060942A (en) * | 2018-08-31 | 2018-12-21 | 南京航空航天大学 | Steel rail defect depth detection method based on leakage magnetic detection device |
| CN109060944A (en) * | 2018-08-31 | 2018-12-21 | 南京航空航天大学 | Steel rail defect depth detection method based on leakage magnetic detection device and neural network |
| CN109737899A (en) * | 2019-01-25 | 2019-05-10 | 北京科技大学 | A kind of metal material crack-type defect depth measurement device and method |
Non-Patent Citations (3)
| Title |
|---|
| J L SHEN 等: "Determining the propagation angle for non-vertical surface-breaking cracks and its effect on crack sizing using an ACFM sensor", 《MEASUREMENT SCIENCE AND TECHNOLOGY》 * |
| JIALONG SHEN: "Responses of Alternating Current Field Measurement (ACFM) to Rolling Contact Fatigue (RCF) Cracks in Railway Rails", 《A THESIS SUBMITTED FOR THE DEGREE OF PHD AT THE UNIVERSITY OF WARWICK》 * |
| 刘彤 等: "疲劳裂纹深度自动监测系统的研制与应用", 《机械强度》 * |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110926942A (en) * | 2019-11-19 | 2020-03-27 | 西安理工大学 | Numerical analysis method for rolling contact fatigue cracks of rails in ABAQUS |
| CN110926942B (en) * | 2019-11-19 | 2022-01-07 | 西安理工大学 | Numerical analysis method for rolling contact fatigue cracks of rails in ABAQUS |
| CN111855448A (en) * | 2020-07-31 | 2020-10-30 | 东风商用车有限公司 | Metal material rolling contact fatigue test crack detection method |
| CN113030187A (en) * | 2021-03-05 | 2021-06-25 | 桂林理工大学 | Method for representing three-dimensional size of steel rail rolling contact fatigue crack cluster in electromagnetic nondestructive mode |
| CN112857197A (en) * | 2021-04-09 | 2021-05-28 | 中国石油大学(华东) | Rotating electromagnetic field non-ferromagnetic material crack size measurement method |
| CN112857197B (en) * | 2021-04-09 | 2022-04-19 | 中国石油大学(华东) | Rotating electromagnetic field non-ferromagnetic material crack size measurement method |
| CN113433060A (en) * | 2021-06-23 | 2021-09-24 | 马鞍山钢铁股份有限公司 | Method for evaluating rolling contact fatigue performance of railway locomotive wheel surface |
| CN113390955A (en) * | 2021-07-08 | 2021-09-14 | 中国石油大学(华东) | Visual monitoring and evaluation method for cracks of alternating current magnetic field |
| CN113390955B (en) * | 2021-07-08 | 2022-04-19 | 中国石油大学(华东) | Visual monitoring and evaluation method for cracks of alternating current magnetic field |
| 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 |
| CN114543656A (en) * | 2022-03-07 | 2022-05-27 | 桂林理工大学 | Method for reconstructing rail complex asymmetric surface crack propagation shape based on alternating current electromagnetic field |
| CN114543656B (en) * | 2022-03-07 | 2024-02-06 | 桂林理工大学 | Rail asymmetric crack growth shape reconstruction method based on alternating current electromagnetic field |
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