CN105973938B - Impulse eddy current thermal imaging high-speed detection device for rail nondestructive inspection - Google Patents
Impulse eddy current thermal imaging high-speed detection device for rail nondestructive inspection Download PDFInfo
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- CN105973938B CN105973938B CN201610513431.7A CN201610513431A CN105973938B CN 105973938 B CN105973938 B CN 105973938B CN 201610513431 A CN201610513431 A CN 201610513431A CN 105973938 B CN105973938 B CN 105973938B
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- rail
- eddy current
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- magnet frame
- thermal imaging
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N25/00—Investigating or analyzing materials by the use of thermal means
- G01N25/72—Investigating presence of flaws
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61K—AUXILIARY EQUIPMENT SPECIALLY ADAPTED FOR RAILWAYS, NOT OTHERWISE PROVIDED FOR
- B61K9/00—Railway vehicle profile gauges; Detecting or indicating overheating of components; Apparatus on locomotives or cars to indicate bad track sections; General design of track recording vehicles
- B61K9/08—Measuring installations for surveying permanent way
- B61K9/10—Measuring installations for surveying permanent way for detecting cracks in rails or welds thereof
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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
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- Engineering & Computer Science (AREA)
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- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
Abstract
The invention discloses the impulse eddy current thermal imaging high-speed detection devices for rail nondestructive inspection, it is characterised by comprising: the magnet frame under being mounted on compartment, several permanent magnets being mounted in magnet frame, it is mounted on the thermal infrared imager of magnet frame end, and data acquisition/memory and computer, the pole orientation of adjacent permanent is opposite, the permanent magnet and magnet frame being mounted in magnet frame, rail forms the magnetization cycle of multiple closures, the signal output end of thermal infrared imager is connect with data acquisition/memory signals input terminal, the connection of the signal input part of data acquisition/memory signals output end and computer.The present invention cuts the magnetic induction line that is perpendicularly to the direction of movement according to rail, and the temperature distribution information formed in Rail Surface is, it can be achieved that detection to rail cracks defect.The present invention can greatly improve the detection efficiency of rail, and manufacturing cost is low, have extremely important meaning to the detection of rail.
Description
Technical field
The present invention relates to rail technical field of nondestructive testing, and in particular to a kind of based on the lossless for rail of dynamic raw vortex
The high-speed lossless of all directions defect horizontal to rail/vertical can be achieved at the same time in the impulse eddy current thermal imaging high-speed detection device of flaw detection
Detection.
Background technique
The operational safety problem of fast development with high-speed railway in China, train increasingly attracts people's attention,
Basis of the rail as railway transportation, the quality of state are directly related to safety of railway traffic.Therefore, domestic and international railway department
It begins to carry out various non-destructive testings to rail very early, to guarantee the safe operation of train.Currently, rail non-destructive testing technology master
There are ultrasonic wave, machine vision, alternation vortex, alternating electromagnetism field detecting, Magnetic Flux Leakage Inspecting technology etc..
Currently, the speed of service for the bullet train that China comes into operation is 200-350km/h.And current non-destructive testing skill
Art is unable to reach such detection speed mostly.The used eddy-current technique of German federal investigation of materials testing research carries out rail inspection
It surveys, Eurailscout company further developed UDT02 shaped steel rail inspection car, and highest detection speed is vortexed up to 80km/h
Detection can not detect underbead crack, and be unable to satisfy detection rate request.TSC company develops railroad track alternating electromagnetic field
(ACFM) detection system, when sample frequency reaches 50kHZ, manual system can realize the detection speed per hour of 2.7km/h, and detection speed is still
It is old very low, and as EDDY CURRENT, internal injury can not be detected.Societe Nationale des Chemins de fer Francais (SNCF) (SNFC) passes through high-speed camera
Machine detects rail uniformity defect, and speed is up to 320km/h, but high-speed camera can only detect the surface shape of rail
State is not available for internal flaw detection.And Magnetic Flux Leakage Inspecting technology can only detect the transverse defect of rail, i.e., lack perpendicular to rail is axial
It falls into, and fails to longitudinal defect.
The impulse eddy current of the prior art studies discovery: when being passed through alternating current in induction coil, being placed near coil
Conductor in can generate vortex of inducting, when existing defects in the test specimen of conductive material, vortex will be forced to lead to portion around defect
Subregion vortex density increases or reduces.According to Joule's law, conductor, which generates heat, uneven distribution will occurs, be set using infrared
Surface of test piece temperature distribution image under note can analyze the characteristic for obtaining test specimen.Ben Weekes etc. uses induced thermal imaging
Metal surface micro-crack is detected, finds the current impulse eddy current thermal imaging of technology sensitivity with higher
Rail context of detection application also comparative maturity but be both used in testee it is static in the case where.But due to this pulse whirlpool
The stream heating method induction heating time is 200ms-500ms, cannot achieve the real-time detection to rail cracks, and detection speed is low.
In conclusion existing rail non-destructive testing technology or high detection speed cannot be reached, or cannot be real
It is detected while existing all directions crackle, the development practice of high-speed railway, it would be highly desirable to which it is real that scientific worker researchs and develops a kind of energy
Technology now synchronous with train operation, that rail all directions crackle is carried out non-destructive testing, to guarantee high-speed cruising train
Driving safety.
Summary of the invention
Status and deficiency, the purpose of the present invention for existing rail nondestructive inspection detection technique are intended to provide one kind and are used for
The impulse eddy current thermal imaging high-speed detection device of rail nondestructive inspection, to solve inspection existing for existing rail non-destructive testing technology
The problem of degree of testing the speed is slower, not can be implemented simultaneously/vertical all directions defect complete detection horizontal to rail.
Provided by the present invention for the impulse eddy current thermal imaging high-speed detection device of rail nondestructive inspection, composition includes:
The magnet frame being mounted under compartment, several permanent magnets being mounted in magnet frame, is mounted on the red of magnet frame end
Outer thermal imaging system and data acquisition/memory and computer, the pole orientation of adjacent permanent is on the contrary, be mounted on magnet frame
On permanent magnet and magnet frame, rail form the magnetization cycles of multiple closures, the signal output end and data of thermal infrared imager
The signal input part of acquisition/memory signals input terminal connection, data acquisition/memory signals output end and computer connects,
The quantity of the permanent magnet is when train advances at utmost speed, and the magnetic induction line that rail cutting is perpendicularly to the direction of movement is inside rail
The heat of generation, it is sufficient to which defect existing for rail is recognized by the Rail Surface thermo parameters method information that thermal infrared imager records.
In the above-mentioned technical solutions, the quantity of the permanent magnet is related with the heat generated inside rail, permanent magnet
Number should generally be no less than 600.Permanent magnet is preferentially arranged using at single array, and thermal infrared imager is arranged in immediately forever
At the position of long magnet array ends.The permanent magnet preferentially uses residual magnetic flux density for the permanent magnet of 1.0~1.4T.
In the above-mentioned technical solutions, the mounting distance between permanent magnet be not more than 20mm, permanent magnet with a thickness of 45
~55mm.
In the above-mentioned technical solutions, the distance between permanent magnet and Rail Surface to be detected for being mounted in magnet frame one
As be not more than 3.0mm, preferably in the range of 1.0~2.0mm.
In the above-mentioned technical solutions, thermal infrared imager detector head is generally no greater than 50mm at a distance from rail.
In the above-mentioned technical solutions, the magnet frame, array of permanent magnets width should be not less than rail width；It is best
It is equal with the width of rail.
In the above-mentioned technical solutions, magnet frame is multistage combined magnet frame, is separately mounted to compartment along rail direction
Lower section, thermal infrared imager are arranged in final stage magnet frame at the immediately position of array of permanent magnets end.
In the above-mentioned technical solutions, the magnet frame is made preferably with high permeability material, such as A3 steel, silicon steel sheet or iron
Ferrite etc..
It, can be by adjusting the installation between permanent magnet in impulse eddy current thermal imaging high-speed detection device provided by the invention
Distance, the travel speed of train, the quantity of permanent magnet, increase or reduce the heating time of eddy current；And then change in rail
The heat that portion generates, convenient for the accurate clearly image of thermal infrared imager record.
It is based on inventor provided by the present invention for the impulse eddy current thermal imaging high-speed detection device of rail nondestructive inspection
What understanding below was completed with inspiration: in the magnetization cycle formed with magnet frame, permanent magnet and rail, train advances at utmost speed
When, rail cuts the magnetic induction line being perpendicularly to the direction of movement, and is based on Faraday's electromagnetic induction law, generates induced electromotive force, in turn
Dynamic raw eddy current is generated, when there are when transverse defect, will hinder the dynamic raw vortex to lead to portion at this in longitudinal propagation in rail
Subregion eddy current increases or reduces, and according to Joule's law, uneven distribution will occur in the heat generated inside rail, utilizes peace
Mounted in the thermo parameters method of the thermal infrared imager record Rail Surface of magnet frame end, so that it may realize the inspection to rail transversal crack
It surveys；When there are when longitudinal crack, will hinder the dynamic raw vortex to lead to partial region eddy current at this in lateral propagation in rail
It increases or reduces, according to Joule's law, uneven distribution will occur in the heat generated inside rail, last using magnet frame is mounted on
The thermo parameters method of the thermal infrared imager record Rail Surface at end, thermo parameters method data information are mentioned by data acquisition/memory
Supply computer is analyzed and processed, and finally obtains the defect information of rail, realizes the detection to Rail Surface crackle.
Provided by the present invention for the impulse eddy current thermal imaging high-speed detection device of rail nondestructive inspection, with following ten
Divide prominent advantage:
1. high speed real-time detection may be implemented.Device is mounted on train bottom, rail cutting magnetic induction line when train advances,
Eddy current is generated, carrying out heating for multiple times to rail will lead to Rail Surface Temperature Distribution not when there are Rail Surface existing defects
?.At this time using the Temperature Distribution of the thermal infrared imager record Rail Surface of fast response time, then pass through computer analysis
Realize the real-time detection to rail.
2. rail cross/longitudinal all directions angle crack detection can be realized.Rail cutting magnetic induction line generates when train driving
Eddy current hinders horizontal/longitudinal propagation of eddy current, affects the distribution situation of vortex, lead when Rail Surface has crackle
It causes the density of eddy current to increase or reduce, the spatial abnormal feature of Joule heat is caused around crackle, is arranged in the infrared heat of end
As instrument can detect rail cracks.
3. being extremely applicable to the high-speed lossless detection of rail.The induced current and train operation that rail cutting magnetic induction line generates
Speed it is directly proportional, the speed of train operation is faster, and the induced current of generation is stronger, move that raw eddy current is stronger, flaw detection it is sensitive
It spends stronger.Therefore, the high-speed lossless that the method is suitable for rail detects.
Detailed description of the invention
Fig. 1 is the impulse eddy current thermal imaging high-speed detection device structural schematic diagram for rail nondestructive inspection.
Fig. 2 is the rail impulse eddy current thermal imaging high speed detection schematic illustration based on dynamic raw vortex.
Fig. 3 is the rail transversal crack detection schematic diagram based on dynamic raw vortex.
Fig. 4 is the rail longitudinal crack detection schematic diagram based on dynamic raw vortex
Fig. 5 is rail transversal crack and longitudinal crack high speed detection schematic illustration based on dynamic raw vortex
Each shown by reference numeral in above-mentioned attached drawing indicates that object is respectively as follows: 1- permanent magnet；2- magnet frame；3- infrared thermal imagery
Instrument；4- rail；5- is closed magnetization cycle；6- discontinuity point；7- transverse defect；8- longitudinal defect；The dynamic raw vortex of 9-.
Specific embodiment
A specific embodiment of the invention is provided with reference to the accompanying drawing, and of the invention is used for by specific embodiment
The impulse eddy current thermal imaging high-speed detection device of rail nondestructive inspection is further described.It is important to note that this hair
Bright specific embodiment is not limited to form described in embodiment.
The direction term being previously mentioned in the specific embodiment below, such as: up, down, left, right, before and after etc., only
It is the direction with reference to attached drawing.Therefore, the direction term used, which is intended merely to facilitate, illustrates the present invention, is not used to limit this hair
It is bright.
The rail pulse thermal imaging high-speed detection device based on dynamic raw vortex of the present embodiment, structure is as shown in Figure 1, structure
At including: the magnet frame 2 being mounted below compartment, the permanent magnet 1 being mounted in magnet frame is mounted on red in magnet frame
Outer thermal imaging system 3.The pole orientation of the permanent magnet being mounted in magnet frame, adjacent permanent is opposite.2, two magnetic of magnet frame
The permanent magnet 1 and rail 4 of pole opposite direction arrangement form closure magnetization cycle.Magnet frame is constituted by three sections, is arranged in phase
Below three adjacent section compartments, intermediate one section of magnet frame is equipped with 400 permanent magnets, and two sections of front and back magnet frame is installed respectively
There are 250 permanent magnets, thermal infrared imager 3 is arranged in one section of magnet frame next the immediately position of array of permanent magnets end
Place.The width of magnet frame and permanent magnet is equal with the width of rail, permanent magnet at a distance from Rail Surface 1.0~
Between 2.0mm, thermal infrared imager probe is at a distance from Rail Surface between 40~50mm.The signal output end of thermal infrared imager
It is connect with data acquisition/memory signals input terminal, data acquisition/memory signals output end and computer signal input part
Connection.It is mounted on permanent magnet and thermal infrared imager probe in magnet frame as detection device main part, with train
Movement, for linear motion in 4 upper surface of rail, thermal infrared imager 3 records the temperature variations of Rail Surface, by what is be collected into
Information passes to computer disposal, finally obtains the defect information of Rail Surface.
Rail is detected using apparatus of the present invention, the principle that the transverse defect 7 in rail is detected is as shown in Figure 2.Magnetic
The magnetization cycle of brandreth 2, rail 4 and the composition closure of permanent magnet 1, when magnet frame 2 is advanced with train with speed V, rail 4
The vertical component of continuous cutting magnetic induction line, is based on Faraday's electromagnetic induction law, generates induced electromotive force, and then generate such as Fig. 5
Shown in move raw eddy current 9.When in rail there are when transverse defect 7, as shown in figure 3, the crackle hinders eddy current in rail
Longitudinal propagation, causes the eddy current density on crackle periphery to significantly increase, according to Joule's law, the joule heat distribution on crackle periphery
Abnormal, the temperature for eventually leading to crackle periphery is apparently higher than area free from defect.Based on impulse eddy current thermal imaging principle, it is located at magnet
The presence of transversal crack 7 can be detected in the thermal infrared imager 3 of frame end.
Likewise, as shown in figure 4, when, there are when longitudinal crack 8, which hinders eddy current in rail transverse direction in rail
Propagation, cause the eddy current density on crackle periphery to significantly increase, according to Joule's law, the joule heat distribution on crackle periphery is different
Often, the temperature for eventually leading to crackle periphery is apparently higher than area free from defect.Based on impulse eddy current thermal imaging principle, it is located at magnet frame
The presence of transversal crack 8 can be detected in the thermal infrared imager 3 of end.
So can fast and accurately be realized using detection device of the present invention to all directions chink line horizontal in rail/vertical
High speed detection.
Claims (8)
1. a kind of impulse eddy current thermal imaging high-speed detection device for rail nondestructive inspection, characterized by comprising: be mounted on
Magnet frame (2) under compartment, several permanent magnets (1) being mounted in magnet frame, is mounted on the red of magnet frame end
Outer thermal imaging system (3) and data acquisition memory and computer, the pole orientation of adjacent permanent is on the contrary, be mounted on magnet
Permanent magnet on frame and magnet frame, rail (4) form the magnetization cycle of multiple closures, the signal output end of thermal infrared imager with
The signal input part of the connection of data acquisition memory signal input part, data acquisition memory signal output end and computer connects
It connects, the quantity of the permanent magnet is no less than 600, arranges at single array, and thermal infrared imager is arranged in immediately permanent magnet
At the position of array ends, when train advances at utmost speed, rail cuts the magnetic induction line being perpendicularly to the direction of movement, and produces inside rail
The Rail Surface thermo parameters method information that raw heat is sufficient to make thermal infrared imager to record can recognize defect existing for rail.
2. the impulse eddy current thermal imaging high-speed detection device according to claim 1 for rail nondestructive inspection, feature
Be: the residual magnetic flux density of the permanent magnet is 1.0~1.4T.
3. the impulse eddy current thermal imaging high-speed detection device according to claim 2 for rail nondestructive inspection, feature
Be: mounting distance between permanent magnet no more than 20mm, permanent magnet with a thickness of 45~55mm.
4. according to claim 1 to described in one of 3 be used for rail nondestructive inspection impulse eddy current thermal imaging high-speed detection device,
It is characterized by: the permanent magnet of array is not more than 3.0mm at a distance from rail.
5. according to claim 1 to described in one of 3 be used for rail nondestructive inspection impulse eddy current thermal imaging high-speed detection device,
It is characterized by: thermal infrared imager detector head is not more than 50mm at a distance from rail.
6. according to claim 1 to described in one of 3 be used for rail nondestructive inspection impulse eddy current thermal imaging high-speed detection device,
It is characterized by: the width of magnet frame, array of permanent magnets is not less than the width of rail.
7. the impulse eddy current thermal imaging high-speed detection device according to claim 6 for rail nondestructive inspection, feature
Be: magnet frame, the width of array of permanent magnets are equal with the width of rail.
8. according to claim 1 to described in one of 3 be used for rail nondestructive inspection impulse eddy current thermal imaging high-speed detection device,
It is characterized by: magnet frame is multistage combined magnet frame, it is separately mounted to below compartment along rail direction, thermal infrared imager
It is arranged in final stage magnet frame at the immediately position of array of permanent magnets end.
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| CN107941855A (en) * | 2017-11-22 | 2018-04-20 | 四川大学 | A kind of pipe end thermal imaging detection device based on permanent magnet rotary heating |
| CN109060825B (en) * | 2018-08-14 | 2020-03-27 | 四川大学 | Nondestructive testing method based on pulsed airflow excitation infrared imaging and implementation device thereof |
| CN110108787B (en) * | 2019-05-07 | 2021-01-05 | 电子科技大学 | Rotatory metal component electromagnetism nondestructive test device based on motional vortex |
| CN111678948B (en) * | 2020-06-02 | 2022-07-19 | 四川大学 | High-speed nondestructive detection method for surface defects of steel rail and implementation device thereof |
| CN112461893B (en) * | 2020-11-05 | 2022-11-22 | 宁波晶成机械制造有限公司 | Nondestructive testing device and method based on thermal imaging principle |
| CN113804727B (en) * | 2021-08-30 | 2022-06-14 | 电子科技大学 | Eddy current thermal imaging defect reconstruction method based on electrical impedance imaging |
| CN117601923B (en) * | 2023-11-28 | 2024-04-30 | 唐山中弘智能科技有限公司 | Automatic inspection system for rail flaw detection |
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| JPH08226914A (en) * | 1995-02-21 | 1996-09-03 | Mitsubishi Heavy Ind Ltd | Eddy-current flaw detector |
| CN104764770A (en) * | 2015-03-30 | 2015-07-08 | 南京航空航天大学 | Pulsed eddy current infrared thermal imaging detection system and method for steel rail cracks |
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