CN109813800A - It is sensed based on optical fiber magnetic and combines collection magnetic surface scanning cannula defect inspection method and device - Google Patents
It is sensed based on optical fiber magnetic and combines collection magnetic surface scanning cannula defect inspection method and device Download PDFInfo
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- CN109813800A CN109813800A CN201910132664.6A CN201910132664A CN109813800A CN 109813800 A CN109813800 A CN 109813800A CN 201910132664 A CN201910132664 A CN 201910132664A CN 109813800 A CN109813800 A CN 109813800A
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Abstract
The invention belongs to lossless defects detection fields, it is that collection magnetic surface scanning cannula defect inspection method and device are combined based on optical fiber magnetic sensing, including sensing light source module, array photoelectric conversion module, two block permanent magnets, optical fiber magnetic susceptibility head array, circumferential fixing by gross bearings module and signal processing module etc., on the one hand magnetic surface is collected with same polarity formation staggered relatively by two block permanent magnets, scans oil gas casing；On the other hand then optical fiber magnetic susceptibility head is arranged, accurately the change of magnetic field strength in perception collection magnetic surface circumferential direction orientation in certain array, realizes that the high-space resolution of oil/gas well casing imperfection is accurately positioned detection.
Description
Technical field
The invention belongs to lossless defects detection field, be related to a kind of oil/gas well casing imperfection detection device, in particular to one
Kind Fiber Optic Weak Magnetic Field sensing combines the oil/gas well casing imperfection detection method of collection magnetic surface scanning.
Background technique
Oil and natural gas is that main energy sources used at present one of are deposited, and in its recovery process, the casing of underground is played
Transmission and protective effect.Cause accident to occur due to corrosion, wear and accidental injury etc. again and again, not only causes huge
Economic loss, and seriously pollute environment, endanger the health of the mankind.
The detection method of existing ferromagnetism down-hole casing mainly has leakage method.Magnetic Flux Leakage Inspecting be to be automated as purpose and
A kind of automatic Nondestructive to grow up, it is similar with Magnetic testing, the common sensor of Magnetic Flux Leakage Inspecting have induction coil,
Magnetodiode (SMD), tape, fluxgate, magnetic probe, Hall element etc., there is also such as these sensors in actual use
Lower problem:
1. the sensitivity of these sensors is lower, faint magnetic leakage signal is detected to realize, generally requires to be close to casing
Wall, for sensor because moving serious wear, sensor service life is very short.
2. longitudinal space resolution is determined by detecting module volume, movement velocity and data sample rate, under array detection,
High sampling rate difficult to realize, that is, be difficult to obtain longitudinal high-space resolution defects detection.
3. the principle of induction coil is electromagnetic induction principle, i.e., the conductor of closed circuit is when the magnetic field intercepts magnetic line of force moves
Electric current can be generated, to convert electric signal for magnetic signal, electric spark phenomenon can be generated, safe coefficient is low；
4. magnetodiode reduces measurement accuracy because of its temperature coefficient and the non-linear of output to a certain extent；
5. it is high that tape detects subtraction unit complexity degree；
6. fluxgate sensor can only detect Slowly Varying magnetic field and static magnetic field, application range is narrow；
Prevent it from being used widely 7. magnetic probe measurement range is narrow, magnetic conductivity is non-linear；
8. Hall element device is more crisp, rapid wear, sensitivity is not high enough.
Summary of the invention
In order to solve the above technical problems, one technical scheme adopted by the invention is that: a kind of Fiber Optic Weak Magnetic Field sensing combination collection
The oil/gas well casing imperfection detection device of magnetic surface scanning, including sensing light source module, photoelectric conversion module, two block permanent magnets, light
Fine magnetic susceptibility head array, circumferential fixing by gross bearings module and signal processing module etc..In particular to a kind of Fiber Optic Weak Magnetic Field sensing knot
The oil/gas well casing imperfection detection method of intersection magnetic surface scanning, on the one hand by two block permanent magnets with same polarity formation staggered relatively
Collect magnetic surface, scans oil gas casing；On the other hand then optical fiber magnetic susceptibility head is arranged in certain array, accurately perception collection magnetic
Change of magnetic field strength in the circumferential direction orientation of face realizes that the high-space resolution of oil/gas well casing imperfection is accurately positioned detection.
The sensing light source module inputs certain power and wavelength to the optical fiber magnetic susceptibility head array through fiber coupler
Lightwave signal；
Two block permanent magnet, it is staggered relatively with same polarity, collection magnetic surface is formed by the adjustment of two magnet strengths and distance,
Oil gas casing is scanned along depth direction with certain speed, when encountering casing imperfection, collects magnetic field strength on magnetic surface and changes；
The optical fiber magnetic susceptibility head array is arranged between two blocks of magnet, is located on collection magnetic surface；The circumferential direction fixing by gross bearings module, can be with
Perceive the circumferential dimensional orientation of some optical fiber magnetic susceptibility head；The optical signal is converted electric signal by the photoelectric conversion module；
The electric signal that the signal processing module exports photoelectric conversion module is handled, and obtains casing imperfection feature and positioning.
Further, the fiber coupler and the optical fiber magnetic susceptibility head array, sensing light source and photoelectric conversion part
It is connected by signal transmission fiber.
Further, the permanent magnet, optical fiber magnetic susceptibility head array, circumferential fixing by gross bearings module coaxial packaging are in one,
Under the effect of certain device, moved in oil gas casing along depth direction.
Further, the F-P cavity and giant magnetostrictive material structure that the optical fiber magnetic susceptibility head is made of broadband chirp grating
At all -fiber magnetic susceptibility unit, external magnetic field intensity size is obtained by phase of light wave demodulation process, the small, magnetic field with volume
The high feature of detectivity.
Further, the optical signal for exporting the optical fiber magnetic susceptibility head is converted telecommunications by the photoelectric conversion module
Number, it is sent to the signal processing module and carries out processing acquisition defect characteristic and location information；The circumferential direction fixing by gross bearings module
Obtain the circumferential azimuth information of some optical fiber magnetic susceptibility head.
The working principle that Fiber Optic Weak Magnetic Field sensing of the present invention combines the oil/gas well casing imperfection of collection magnetic surface scanning to detect is: when two
When block magnet is staggered relatively with same polarity, the magnetic line of force issued will be compressed to form plane, pass through two magnet strengths and interval
Distance adjustment forms thin collection magnetic surface.Collect magnetic surface and scan oil gas casing, when encountering casing imperfection, collects magnetic surface because of defect magnetic force
Line diverging causes magnetic field strength to change, and recycles the magnetic reaction fields intensity for the optical fiber magnetic susceptibility head output being located on collection magnetic surface
The lightwave signal of variation is output to photoelectric conversion module, is converted into electric signal output signal processing module, and signal processing module is logical
It crosses and electric signal is analyzed, and combine circumferential fixing by gross bearings module, realize defect characteristic and location information output.
It is in contrast to the prior art, the beneficial effects of the present invention are:
(1), by the way that two blocks of magnet are staggered relatively with same polarity, the magnetic line of force of sending is compressed to form thin collection magnetic recording level face,
Using collection magnetic recording level Surface scan oil gas casing, longitudinal space resolution ratio is only decided by collect the thickness of magnetic surface, compared with prior art
Longitudinal space resolution ratio can be effectively improved.
(2) using collection magnetic surface scanning, and the high sensitivity detection of fiber optic weak magnetic field sensor is combined, magnetic-field-sensitive member
Part does not need to be close to casing wall, and the volume of entire measuring device can be done small, on the one hand increases and decreases entire measuring device in casing
Percent of pass, be suitable for the test of a variety of cased well hole diameters without replacing bed sensor array, on the other hand can then increase
Subtract the service life of sensor, reduces working service cost.
(3) safe and reliable lightwave signal is converted by physical transformations mode for leakage field information by magneto-optic converting member,
Wave optical signal is transmitted using signal transmission fiber, anti-electromagnetic interference capability is strong, will not generate electric spark phenomenon, safely may be used
It leans on.
Detailed description of the invention
Fig. 1 is the structural schematic diagram that the present invention implements the pipeline defect and magnetic leakage detection device.
Fig. 2 is that optical fiber magnetic susceptibility head array of the present invention arranges schematic diagram.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that the described embodiments are merely a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
It is sensed based on optical fiber magnetic and combines collection magnetic surface scanning cannula defect detecting device, including sensing light source module, photoelectricity turn
Change the mold block, two block permanent magnets, optical fiber magnetic susceptibility head array and circumferential fixing by gross bearings module；Wherein permanent magnet, optical fiber magnetic susceptibility
Head array and circumferential fixing by gross bearings module carry out coaxial packaging and fix, and move up and down in oil gas casing, carry out to casing
Depth direction scanning, two block permanent magnets are staggered relatively with same polarity, form collection magnetic surface by the adjustment of two magnet strengths and distance,
Collect magnetic surface and scan oil gas casing, when encountering casing imperfection, collects magnetic field strength on magnetic surface and change.
Specifically, the optical fiber magnetic susceptibility head array includes multiple fiber optic weak magnetic field sensing heads, in certain circumferential direction
Space arrangement realizes that 360 degree of casing circumferential collection magnetic surface change of magnetic field strength carry out omnidirectional detection, guarantees oil/gas well casing imperfection
Complete cycle to high spatial resolution detection.
The faint variation for collecting magnetic surface magnetic field strength caused by because of casing imperfection is carried out using fiber optic weak magnetic field sensing head
Detection, fiber optic weak magnetic field sensing head is on the collection magnetic surface between two magnet.
The F-P cavity and giant magnetostrictive material that all -fiber magnetic susceptibility unit is made of broadband chirp grating are made, and lead to
It crosses phase of light wave demodulation process and obtains external magnetic field intensity size.
For the pipeline of different bores, control optical fiber magnetic susceptibility head quantity can be led to, meet different oil gas casing calibers
Defect detection, and guarantee circumferential spatial resolution.
The circumferential direction fixing by gross bearings module includes gyroscope and pressure high-temp resistant encapsulating structure.
The optical fiber magnetic susceptibility head array is two one group of sensing head and is formed in connection in periphery arrangement.
The optical fiber magnetic susceptibility head array is fixed on two neodymium-iron-borons by a fixation member insensitive to magnetic field
Between iron, in the intermediate punching of this component, optical fiber magnetic susceptibility head is fixed in hole
By taking Fig. 1 as an example, sensing the lightwave signal that light source 5 issues as shown in figure 1 is the optical signal with spectrum width and power, and its
The optical signal of output is stability optical signal；Collect 2 permanent magnet of magnetic surface forming member to place using same polarity, it is strong by adjusting magnetic field
Degree and spacing distance form thin collection magnetic surface；It senses light source 5 and connects optical cable 8 and fiber coupling module 4 to optical fiber magnetosensitive through signal
Feel linear transducer array 3 and input lightwave signal, optical fiber magneto-sensitive probe array 3 is arranged on the collection magnetic surface between two magnet；Collect magnetic surface scanning
It is middle because change of magnetic field strength caused by defect causes the lightwave signal returned in optical fiber magneto-sensitive probe array 3 to change, optical fiber magnetic
The lightwave signal for carrying changes of magnetic field is connected optical cable 8 through signal to sensing probe array 3 and fiber coupling module 4 is transferred to battle array
Column photoelectric conversion part 6, array photoelectric converting member 6 convert optical signal into electric signal；Electric signal for signal processing module 7 into
Row analysis；Circumferential fixing by gross bearings module 9 exports location information to signal processing module 7；Signal processing module 7 utilizes changes of magnetic field
Signal and circumferentially positioned information analysis export tested oil/gas well casing imperfection feature and location information.
Wherein, fiber coupling module 4 is that multiple common fiber couplers then claim, and array photoelectric converting member 6 is by multiple
Photodetector and interlock circuit are constituted, and photodetector can select photoconductive detector or photovoltaic commonly used in the art to visit
Survey device.
Wherein, signal processing module 7 is by signal amplification circuit, multichannel A/D data module, embedded computer, storage
Module, USB interface etc. are constituted；In signal processing module 7 be equipped with magnetic field signal Processing Algorithm, array magnetic detection casing Three-Dimensional Magnetic at
As algorithm, flaw indication is handled, analyzed, is judged, to detect the size and location information of tested pipeline defect.
In the present embodiment, optical fiber magnetic susceptibility head array is fixed on two neodymiums by a fixation member insensitive to magnetic field
Between iron boron magnets, in the intermediate punching of this component, optical fiber magnetic susceptibility head is fixed in hole.
In the present embodiment, to part B (fiber coupling module 4, sensing light source 5, array photoelectric converting member 6, signal processing
Module 7) overall package is carried out, it can be placed in ground, connect by optical cable with front end system, it can also (coaxial packaging be solid with part A
Determine beam 1, permanent magnet 2, optical fiber magneto-sensitive probe array 3, circumferential fixing by gross bearings module 9) place underground.
For 3 optical fiber magnetic susceptibility head array of component, the application is described in further detail, the signal of the application and its
Illustrate not constituting an undue limitation on the present application for explaining the application.
The above description is only an embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair
Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content is applied directly or indirectly in other relevant skills
Art field, is included within the scope of the present invention.
Claims (10)
1. combining collection magnetic surface scanning cannula defect detecting device, including sensing light source module, photoelectric conversion based on optical fiber magnetic sensing
Module, two block permanent magnets, optical fiber magnetic susceptibility head array and circumferential fixing by gross bearings module；Wherein permanent magnet, optical fiber magnetic susceptibility head
Array and circumferential fixing by gross bearings module carry out coaxial packaging and fix, and move up and down in oil gas casing, carry out to casing deep
Spend direction scanning, it is characterised in that: two block permanent magnets are staggered relatively with same polarity, pass through the adjustment shape of two magnet strengths and distance
At collection magnetic surface, collection magnetic surface scans oil gas casing, when encountering casing imperfection, collects magnetic field strength on magnetic surface and changes.
2. casing imperfection detection device according to claim 1, it is characterised in that: the optical fiber magnetic susceptibility head array includes
Multiple fiber optic weak magnetic field sensing heads realize that 360 degree of casing circumferential collection magnetic surface magnetic field strengths become in certain circumferential space arrangement
Change carry out omnidirectional detection, guarantee oil/gas well casing imperfection complete cycle to high spatial resolution detection.
3. casing imperfection detection device according to claim 1, it is characterised in that: because of the collection magnetic surface caused by casing imperfection
The faint variation of magnetic field strength is detected using fiber optic weak magnetic field sensing head, and fiber optic weak magnetic field sensing head is located at two magnet
Between collection magnetic surface on.
4. casing imperfection detection device according to claim 1, it is characterised in that: all -fiber magnetic susceptibility unit is by width
The F-P cavity and giant magnetostrictive material constituted with chirp grating is made, and it is strong to obtain external magnetic field by phase of light wave demodulation process
Spend size.
5. casing imperfection detection device according to claim 1, it is characterised in that:, can be with for the pipeline of different bores
Logical control optical fiber magnetic susceptibility head quantity, meets the defect detection of different oil gas casing calibers, and guarantee circumferential spatial resolution.
6. casing imperfection detection device according to claim 1, it is characterised in that: it is described circumferential direction fixing by gross bearings module include
Gyroscope and pressure high-temp resistant encapsulating structure.
7. casing imperfection detection device according to claim 1, it is characterised in that: the optical fiber magnetic susceptibility head array is to pass
Two one group of head of sense is formed in connection in periphery arrangement.
8. casing imperfection detection device according to claim 1, it is characterised in that: the optical fiber magnetic susceptibility head array passes through
One fixation member insensitive to magnetic field is fixed between two ndfeb magnets, in the intermediate punching of this component, by light
Fine magnetic susceptibility head is fixed in hole.
9. casing imperfection detection device according to claim 1, it is characterised in that: the fiber coupling module, sense light
Source, array photoelectric converting member, signal processing module carry out overall package, can be placed in ground, pass through optical cable and front end system
Connection can also place underground with coaxial packaging fixed beam, permanent magnet, optical fiber magneto-sensitive probe array, circumferential fixing by gross bearings module.
10. the oil/gas well casing imperfection flux-leakage detection method that a kind of Fiber Optic Weak Magnetic Field sensing combines collection magnetic surface scanning, which is characterized in that
Using following measuring process and signal processing method:
(1) the integral permanent magnet of coaxial packaging, optical fiber magnetic susceptibility head array, circumferential fixing by gross bearings module dragging in certain device
Under dynamic, moved in oil gas casing along depth direction, realize the comprehensive scanning of casing；
(2) each sensing head of optical fiber magnetic susceptibility head array exports a characteristic curve, with sweeping along tubing depth direction
It retouches, the output of entire array forms two dimensional image；
(3) the corresponding circumferential dimensional orientation of defect that certain characteristic curve in the two dimensional image of array output is embodied is by circumferential direction
The synchronism output of fixing by gross bearings module determines；
(4) the corresponding depth information of defect that certain characteristic curve in the two dimensional image of array output is embodied is by detection device
The depth information of go into the well speed or other well logging apparatus obtain.
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| CN201910132664.6A CN109813800A (en) | 2019-02-22 | 2019-02-22 | It is sensed based on optical fiber magnetic and combines collection magnetic surface scanning cannula defect inspection method and device |
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| CN201910132664.6A CN109813800A (en) | 2019-02-22 | 2019-02-22 | It is sensed based on optical fiber magnetic and combines collection magnetic surface scanning cannula defect inspection method and device |
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Cited By (4)
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| CN110965984A (en) * | 2019-10-23 | 2020-04-07 | 电子科技大学 | Downhole testing optical cable and downhole testing method thereof |
| CN112945091A (en) * | 2020-12-29 | 2021-06-11 | 上海甬兴塑胶有限公司 | Detection apparatus for working of plastics apopore |
| CN114047249A (en) * | 2021-11-11 | 2022-02-15 | 中国计量大学 | Magnetic leakage scanning device based on optical fiber current sensing |
| CN114720553A (en) * | 2022-06-09 | 2022-07-08 | 西北大学 | Pipeline magnetic flux leakage detection device based on optical fiber coupling diamond-nitrogen vacancy color center |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110965984A (en) * | 2019-10-23 | 2020-04-07 | 电子科技大学 | Downhole testing optical cable and downhole testing method thereof |
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