CN117825487A - Small-diameter pipeline flux-weakening magnetic gradient tensor detection device and pipe damage evaluation method - Google Patents
Small-diameter pipeline flux-weakening magnetic gradient tensor detection device and pipe damage evaluation method Download PDFInfo
- Publication number
- CN117825487A CN117825487A CN202311800482.4A CN202311800482A CN117825487A CN 117825487 A CN117825487 A CN 117825487A CN 202311800482 A CN202311800482 A CN 202311800482A CN 117825487 A CN117825487 A CN 117825487A
- Authority
- CN
- China
- Prior art keywords
- small
- component
- magneto
- magnetic field
- diameter pipeline
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 25
- 238000011156 evaluation Methods 0.000 title claims abstract description 11
- 230000008859 change Effects 0.000 claims abstract description 7
- 230000001419 dependent effect Effects 0.000 claims description 29
- 238000000034 method Methods 0.000 claims description 18
- 230000007547 defect Effects 0.000 claims description 13
- 230000002159 abnormal effect Effects 0.000 claims description 11
- 238000005259 measurement Methods 0.000 claims description 8
- 230000007797 corrosion Effects 0.000 claims description 7
- 238000005260 corrosion Methods 0.000 claims description 7
- 239000000523 sample Substances 0.000 claims description 7
- 238000012937 correction Methods 0.000 claims description 6
- 230000003313 weakening effect Effects 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 4
- 230000001066 destructive effect Effects 0.000 claims description 3
- 238000007689 inspection Methods 0.000 claims description 3
- 238000009659 non-destructive testing Methods 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 238000011179 visual inspection Methods 0.000 claims description 3
- 230000008439 repair process Effects 0.000 abstract description 4
- 238000009472 formulation Methods 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005358 geomagnetic field Effects 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The disclosure belongs to the technical field of nuclear power, and particularly relates to a small-diameter pipeline weak magnetic gradient tensor detection device and a pipe damage evaluation method. The magnetic sensor and the tube damage evaluation method are suitable for small-diameter pipeline weak magnetic gradient tensor detection, the magnetic gradient tensor data contains a large amount of magnetic field vector strength and direction change information, the magnetic source boundary position can be determined by utilizing the magnetic field vector strength change information, the scale of stress concentration or damage is determined, and the problem of lack of small-diameter pipeline detection means can be effectively solved. Knowledge of the status of small diameter pipelines will strongly support power plant repair strategy formulation, such as target pipe segment repair or replacement, rather than complete replacement.
Description
Technical Field
The disclosure belongs to the technical field of nuclear power, and particularly relates to a small-diameter pipeline weak magnetic gradient tensor detection device and a pipe damage evaluation method.
Background
Small diameter pipes (diameter between 1/2 inch and 2 inch) are used in industry in large numbers, such as temperature/pressure/flow meter lines, hydrophobic exhaust branch lines. The pipelines can be exposed to chloride environment, so that problems of corrosion of inner walls are easy to occur, such as pitting corrosion leakage caused by chloride ions of the seawater stainless steel instrument pipeline of important plant water of a nuclear power plant, and the important plant water or other systems are not available due to the fact that the pipelines are difficult to isolate during operation, so that unit power reduction or efficiency reduction is caused, and shutdown is caused when serious conditions exist.
Because the laying distance of the small-diameter pipe is long, the arrangement is complex, uncertainty exists in the failure part, the corrosion defect on the pipe section is difficult to effectively detect, the on-site is often relieved by adopting a passive replacement or pressurized plugging mode, and hidden danger and burden are brought to the safe production of the unit.
The weak magnetic detection technology is to scan the surface or near surface of a detection object through a magnetic vector sensor in a natural geomagnetic field environment, judge whether defects exist in a detection sample according to magnetic induction intensity changes in different directions, and can detect the surface of a small-diameter tube on line so as to realize rapid detection. However, the weak magnetic signal generated by the defect is related to the shape, size and distribution of the defect, the direction of the defect is arbitrary, and when the included angle between the detection direction and the trend of the defect is changed, the normal and tangential detection components are changed. In order to improve reliability of damage evaluation of a small-diameter pipeline pipe body, the invention provides a magneto-dependent sensor and a pipe body damage evaluation method suitable for detecting a flux-weakening magnetic gradient tensor of the small-diameter pipeline.
Disclosure of Invention
In order to overcome the problems in the related art, the device for detecting the weak magnetic gradient tensor of the small-diameter pipeline and the method for evaluating the damage of the pipeline body are provided.
According to an aspect of an embodiment of the present disclosure, there is provided a schematic diagram of a small diameter pipeline field weakening magnetic gradient tensor detection device, the device including a plurality of three-component magnetic sensors, a frame, a plurality of lift-off height adjusters, and a scanner;
each three-component magneto-sensitive sensor uses a magneto-sensitive probe configured by a magnetometer for measuring a surface magnetic field of a near-surface area of the small-diameter tube to be measured;
the frame is used for supporting a plurality of three-component magneto-sensitive sensors arranged according to the magnetic gradient tensor and assembling with the scanner;
each measuring module comprises two three-component magneto-sensitive sensors, the three-component magneto-sensitive sensors of different measuring modules are different from each other, the measuring modules are uniformly distributed on the frame and face the small-diameter pipeline, in each measuring module, the two three-component magneto-sensitive sensors are connected with each other through a lifting height adjuster, and the distance between the two three-component magneto-sensitive sensors can be adjusted through adjusting the lifting height adjuster, so that the distance between the two three-component magneto-sensitive sensors in each measuring module is consistent with the diameter of the measured small-diameter pipeline;
the scanner is used for controlling the magneto-dependent sensor to acquire magnetic field and magnetic field gradient data, and a position encoder of the scanner can output the actual probe position in the scanning process in real time.
In one possible implementation, the frame is arc-shaped, and the radian of the frame is matched with the outer surface of the small-diameter pipeline to be tested.
According to another aspect of the embodiments of the present disclosure, there is provided a small-diameter pipe body damage evaluation method, which is implemented based on the small-diameter pipe field weakening magnetic gradient tensor detection device, and includes the following steps:
step 1, carrying a small-diameter pipeline weak magnetic gradient tensor detection device by a detector, advancing along a pipeline mark on a small-diameter pipeline to be detected, and measuring a leakage magnetic field signal on the surface of the small-diameter pipeline;
step 2, obtaining Hx, hy and Hz of a leakage magnetic field on the surface of the small-diameter pipeline, wherein Hx is a magnetic field component in the x direction, hy is a magnetic field component in the y direction and Hz is a magnetic field component in the z direction, the change rate of Hx in the x direction is Hxx, the magnetic field component of Hy in the y direction is Hyy, the magnetic field component of Hz in the z direction is Hzz, hxx, hyy and Hzz form a magnetic gradient tensor, and taking the F-norm of the magnetic gradient tensor as a boundary condition for damage assessment of the small-diameter pipeline body;
and 3, judging whether an abnormal region exists in the small-diameter pipeline or not according to the boundary condition of the small-diameter pipeline body damage assessment determined in the step 2.
In one possible implementation, the method further includes: if the abnormal region is judged to exist, firstly, carrying out visual inspection on the abnormal region to distinguish the abnormal region as a defect positioned on the outer surface or in the outer surface; for internal defects, additional measurements are made using an ultrasonic thickness gauge or other non-destructive inspection method to determine the occurrence of inner wall corrosion or other pipe damage.
In one possible implementation, step 2 further includes:
step 21, for the current position, determining the magnetic gradient tensor G of the measurement module ij by using ij The measuring module ij is any measuring module, and the measuring module ij comprises a three-component magneto-dependent sensor i and a three-component magneto-dependent sensor j:
wherein: dH (dH) xi /d x Representing the magnetic field gradient of sensor i in the x-direction of the pipe space, dH yi /d x Representing the magnetic field gradient of sensor i in the y-direction of the pipe space, dH zi /d x Representing the magnetic field gradient of sensor i in the z-direction of the pipe space; h xi -H xj A slight difference of magnetic fields in the x direction of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j is H yi -H yj A slight difference of magnetic fields in y direction of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j is H zi -H zj The magnetic field light difference delta of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j in the z direction z The distance between the three-component magnetic sensor i and the three-component magnetic sensor j is adjusted to the outer diameter length of the pipeline through a lifting height adjuster;
step 22, determining G using the following formula ij F-norm representation of (c):
step 23, determining the damage level F of the current position of the small-diameter pipeline measured by the measuring module ij according to the following formula ij ：
Wherein A is a correction coefficient, and when the correction coefficient A is determined, the damage grade of the sampling point obtained by the method is consistent with the damage grade obtained by evaluating other verified nondestructive testing data.
In one possible implementation, step 3 further includes: f according to different positions ij And determining the boundary condition of the damage assessment of the small-diameter pipeline body.
The beneficial effects of the present disclosure are: aiming at the problems that the failure part of the small-diameter pipe of the in-service power plant is uncertain and the corrosion defect on the pipe section is difficult to effectively detect, the disclosure provides a magneto-sensor and pipe damage evaluation method suitable for detecting the flux-weakening magnetic gradient tensor of the small-diameter pipe, wherein the flux-weakening magnetic gradient tensor data comprises a large amount of magnetic field vector strength and direction change information, the boundary position of a magnetic source can be determined by utilizing the magnetic field vector strength change information, the scale of stress concentration or damage is determined, and the problem that the detection means of the small-diameter pipe is lack can be effectively solved. Knowledge of the status of small diameter pipelines will strongly support power plant repair strategy formulation, such as target pipe segment repair or replacement, rather than complete replacement.
Drawings
FIG. 1 is a schematic diagram of a small diameter pipeline flux weakening gradient tensor detection device;
FIG. 2 is a schematic diagram of a magnetic sensor channel distribution;
fig. 3 is a schematic diagram of a scanning device in the small-diameter pipeline detection process.
In the figure:
1. a small diameter pipe; 2. a three-component magneto-dependent sensor; 3. a frame;
4. lifting off the height adjuster; 5. a scanner.
Detailed Description
The disclosure is further described in detail below with reference to the drawings and specific examples.
Fig. 1 is a schematic diagram of a small diameter pipeline flux weakening gradient tensor detection device, which, as shown in fig. 1, comprises a plurality of three-component magnetosensitive sensors 2, a frame 3, a plurality of lifting height regulators 4 and a scanner 5.
Each three-component magneto-sensitive sensor 2 uses a magnetometer-configured magneto-sensitive probe for measuring the surface magnetic field of the near-surface region of the small diameter tube under test.
The frame 3 is used for supporting a plurality of three-component magneto-sensitive sensors 2 arranged according to magnetic gradient tensors and for assembly with a scanner 5.
Each measuring module comprises two three-component magneto-sensitive sensors 2 (the three-component magneto-sensitive sensors of different measuring modules are different from each other), the measuring modules are uniformly distributed on the frame 3 and face the small-diameter pipeline 1, in each measuring module, the two three-component magneto-sensitive sensors 2 are connected with each other through one lifting height adjuster 4, the distance between the two three-component magneto-sensitive sensors 2 can be adjusted through adjusting the lifting height adjuster 4, so that the distance between the two three-component magneto-sensitive sensors 2 in each measuring module is consistent with the diameter of the measured small-diameter pipeline 1 (for example, the lifting height adjuster can be a screw or a telescopic sleeve rod, as long as the lifting height adjuster can adjust the distance between the two three-component magneto-sensitive sensors, the type of the lifting height adjuster is not limited, and the adjusting distance of the lifting height adjuster can be between 1/2 inch and 2 inch).
As shown in fig. 3, the scanner 5 is configured to control the magneto-sensitive sensor to acquire magnetic field and magnetic field gradient data, and a position encoder of the scanner 5 can output an actual probe position in the scanning process in real time.
In one possible implementation manner, the frame is arc-shaped, the radian of the frame is matched with the outer surface of the small-diameter pipeline to be measured, and the plurality of measuring modules are uniformly distributed on the frame and face the small-diameter pipeline.
In one possible implementation manner, a small-diameter pipeline body damage evaluation method is provided, the method is implemented based on the small-diameter pipeline field weakening magnetic gradient tensor detection device, and the method comprises the following steps:
step 1, carrying a small-diameter pipeline weak magnetic gradient tensor detection device by a detector, advancing along a pipeline mark on a small-diameter pipeline to be detected, and measuring a leakage magnetic field signal on the surface of the small-diameter pipeline;
and 2, obtaining Hx, hy and Hz of a leakage magnetic field on the surface of the small-diameter pipeline, wherein Hx is a magnetic field component in the x direction, hy is a magnetic field component in the y direction and Hz is a magnetic field component in the z direction, the change rate of Hx in the x direction is Hxx, the magnetic field component of Hy in the y direction is Hyy, the magnetic field component of Hz in the z direction is Hzz, and the Hxx, hyy and Hzz form a magnetic gradient tensor. Taking the norm (Frobenius) of the magnetic gradient tensor as a boundary condition of the small-diameter pipeline body damage assessment.
Determining the magnetic gradient tensor G of the measurement module ij by ij The measurement module ij comprises a three-component magneto-dependent sensor i and a three-component magneto-dependent sensor j:
wherein: dH (dH) xi /d x Representing the magnetic field gradient of sensor i in the x-direction of the pipe space, dH yi /d x Representing the magnetic field gradient of sensor i in the y-direction of the pipe space, dH zi /d x Representing the magnetic field gradient of sensor i in the z-direction of the pipe space;
H xi -H xj a slight difference of magnetic fields in the x direction of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j is H yi -H yj A slight difference of magnetic fields in y direction of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j is H zi -H zj The magnetic field light difference delta of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j in the z direction z The distance between the three-component magnetic sensor i and the three-component magnetic sensor j is adjusted to the outer diameter length of the pipeline through the lifting height adjuster.
G ij The F-norm expression of (c) is as follows:
determining the damage grade F of the current position of the small-diameter pipeline measured by the measuring module ij according to the following formula ij ：
Wherein A is a correction coefficient, and when the correction coefficient A is determined, the damage grade of the sampling point obtained by the method is consistent with the damage grade obtained by evaluating other verified nondestructive testing data.
For example, as shown in FIG. 2, three-component magneto-dependent sensors 1# -2#, 3# -4#, 5# -6#, 7# -8# are arranged in an array,respectively forming 4 groups of detection modules, and acquiring the position information and F corresponding to each detection module ij ，(F ij Is F 12 、F 34 、F 56 、F 78 ) F according to different positions ij And determining the boundary condition of the damage assessment of the small-diameter pipeline body.
In one possible implementation, when an abnormal area exists through finding out the small-diameter pipeline, firstly, performing visual inspection on the abnormal area to distinguish the abnormal area from the defect positioned on the outer surface or the inside; for internal defects, additional measurements are made using an ultrasonic thickness gauge or other non-destructive inspection method to determine the occurrence of inner wall corrosion or other pipe damage.
The foregoing description of the embodiments of the present disclosure has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the improvement of technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
Claims (6)
1. The device is characterized by comprising a plurality of three-component magneto-sensitive sensors, a frame, a plurality of lifting height regulators and a scanner;
each three-component magneto-sensitive sensor uses a magneto-sensitive probe configured by a magnetometer for measuring a surface magnetic field of a near-surface area of the small-diameter tube to be measured;
the frame is used for supporting a plurality of three-component magneto-sensitive sensors arranged according to the magnetic gradient tensor and assembling with the scanner;
each measuring module comprises two three-component magneto-sensitive sensors, the three-component magneto-sensitive sensors of different measuring modules are different from each other, the measuring modules are uniformly distributed on the frame and face the small-diameter pipeline, in each measuring module, the two three-component magneto-sensitive sensors are connected with each other through a lifting height adjuster, and the distance between the two three-component magneto-sensitive sensors can be adjusted through adjusting the lifting height adjuster, so that the distance between the two three-component magneto-sensitive sensors in each measuring module is consistent with the diameter of the measured small-diameter pipeline;
the scanner is used for controlling the magneto-dependent sensor to acquire magnetic field and magnetic field gradient data, and a position encoder of the scanner can output the actual probe position in the scanning process in real time.
2. The device of claim 1, wherein the frame is arcuate in shape, and the curvature of the frame matches the outer surface of the small diameter pipe to be measured.
3. The small-diameter pipeline body damage evaluation method is characterized by being realized based on the small-diameter pipeline field weakening magnetic gradient tensor detection device, and comprises the following steps of:
step 1, carrying a small-diameter pipeline weak magnetic gradient tensor detection device by a detector, advancing along a pipeline mark on a small-diameter pipeline to be detected, and measuring a leakage magnetic field signal on the surface of the small-diameter pipeline;
step 2, obtaining Hx, hy and Hz of a leakage magnetic field on the surface of the small-diameter pipeline, wherein Hx is a magnetic field component in the x direction, hy is a magnetic field component in the y direction and Hz is a magnetic field component in the z direction, the change rate of Hx in the x direction is Hxx, the magnetic field component of Hy in the y direction is Hyy, the magnetic field component of Hz in the z direction is Hzz, hxx, hyy and Hzz form a magnetic gradient tensor, and taking the F-norm of the magnetic gradient tensor as a boundary condition for damage assessment of the small-diameter pipeline body;
and 3, judging whether an abnormal region exists in the small-diameter pipeline or not according to the boundary condition of the small-diameter pipeline body damage assessment determined in the step 2.
4. A method according to claim 3, characterized in that the method further comprises: if the abnormal region is judged to exist, firstly, carrying out visual inspection on the abnormal region to distinguish the abnormal region as a defect positioned on the outer surface or in the outer surface; for internal defects, additional measurements are made using an ultrasonic thickness gauge or other non-destructive inspection method to determine the occurrence of inner wall corrosion or other pipe damage.
5. A method according to claim 3, wherein step 2 further comprises:
step 21, for the current position, determining the magnetic gradient tensor G of the measurement module ij by using ij The measuring module ij is any measuring module, and the measuring module ij comprises a three-component magneto-dependent sensor i and a three-component magneto-dependent sensor j:
wherein: dH (dH) xi /d x Representing the magnetic field gradient of sensor i in the x-direction of the pipe space, dH yi /d x Representing the magnetic field gradient of sensor i in the y-direction of the pipe space, dH zi /d x Representing the magnetic field gradient of sensor i in the z-direction of the pipe space; h xi -H xj A slight difference of magnetic fields in the x direction of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j is H yi -H yj A slight difference of magnetic fields in y direction of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j is H zi -H zj The magnetic field light difference delta of the distance between the three-component magneto-dependent sensor i and the three-component magneto-dependent sensor j in the z direction z The distance between the three-component magnetic sensor i and the three-component magnetic sensor j is adjusted to the outer diameter length of the pipeline through a lifting height adjuster;
step 22, determining G using the following formula ij F-norm representation of (c):
step 23, determining according to the following formulaThe fixed measurement module ij measures the damage grade F of the current position of the small-diameter pipeline ij ：
Wherein A is a correction coefficient, and when the correction coefficient A is determined, the damage grade of the sampling point obtained by the method is consistent with the damage grade obtained by evaluating other verified nondestructive testing data.
6. The method of claim 5, wherein step 3 further comprises: f according to different positions ij And determining the boundary condition of the damage assessment of the small-diameter pipeline body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311800482.4A CN117825487A (en) | 2023-12-26 | 2023-12-26 | Small-diameter pipeline flux-weakening magnetic gradient tensor detection device and pipe damage evaluation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311800482.4A CN117825487A (en) | 2023-12-26 | 2023-12-26 | Small-diameter pipeline flux-weakening magnetic gradient tensor detection device and pipe damage evaluation method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117825487A true CN117825487A (en) | 2024-04-05 |
Family
ID=90510631
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311800482.4A Pending CN117825487A (en) | 2023-12-26 | 2023-12-26 | Small-diameter pipeline flux-weakening magnetic gradient tensor detection device and pipe damage evaluation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117825487A (en) |
-
2023
- 2023-12-26 CN CN202311800482.4A patent/CN117825487A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8447532B1 (en) | Metallic constructions integrity assessment and maintenance planning method | |
| EP2808677B1 (en) | Method for non-contact metallic constructions assessment | |
| Jarvis et al. | Performance evaluation of a magnetic field measurement NDE technique using a model assisted Probability of Detection framework | |
| Zhou et al. | Non-magnetization detection of arbitrary direction defects in coiled tubing based on fluxgate sensor | |
| CN102323332A (en) | The method of balance eddy current array system on the test object of quality the unknown | |
| CN101694478B (en) | Method for detecting internal corrosion of steel pipeline | |
| Zhou et al. | Recognizing coiled tubing defect characteristics based on weak magnetic detection technology | |
| CN117235433B (en) | Metal surface crack quantitative evaluation method based on alternating current magnetic field | |
| WO2016076316A1 (en) | Eddy-current flaw detection device and eddy-current flaw detection method | |
| CN105806936B (en) | A kind of data analysing method of defect inspection device | |
| CN117825487A (en) | Small-diameter pipeline flux-weakening magnetic gradient tensor detection device and pipe damage evaluation method | |
| KR101463444B1 (en) | Apparatus for detecting coolant leakage of reactor pressure vessel and method for detecting coolant leakage using the same | |
| Bian et al. | Crack identification and quantification methods under the condition of lift-off effect using alternating current field measurement technique | |
| RU2536778C1 (en) | Method of detection of local defects of metal of buried pipeline | |
| CN107178710B (en) | It is a kind of based on it is inside and outside detection signal characteristic abstraction defect of pipeline inside and outside discrimination method | |
| JP2016173340A (en) | Pipeline inspection device | |
| Li et al. | Theoretical study on the characteristics of self-magnetic flux leakage signals from pipeline defects | |
| JP2006138784A (en) | Eddy current flaw detection probe and eddy current flaw detection system | |
| Al-Qadeeb | Tubing inspection using multiple NDT techniques | |
| Endo et al. | Signal evaluation system of flexible array ECT probes for inspecting complexly shaped surfaces | |
| KR101835650B1 (en) | Compensation apparatus of circumferentially arrayed magnetic sensors | |
| RU2778718C1 (en) | Device for in-line determination of mechanical stresses in pipeline | |
| CN104391036A (en) | Gas storage well wellbore defect detection method | |
| Wang et al. | Research on the error correction algorithm for caliper center offset in the offshore pipeline | |
| Stroebele et al. | Developing an inline pipe wall screening tool for assessing and managing metallic pipe |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |