CN106404901A - Anti-interference pulsed eddy current testing method - Google Patents
Anti-interference pulsed eddy current testing method Download PDFInfo
- Publication number
- CN106404901A CN106404901A CN201610995683.8A CN201610995683A CN106404901A CN 106404901 A CN106404901 A CN 106404901A CN 201610995683 A CN201610995683 A CN 201610995683A CN 106404901 A CN106404901 A CN 106404901A
- Authority
- CN
- China
- Prior art keywords
- probe
- pipeline
- radome
- distance
- eddy current
- 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.)
- Granted
Links
Classifications
-
- 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
- G01N27/9046—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 by analysing electrical signals
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D5/00—Protection or supervision of installations
- F17D5/02—Preventing, monitoring, or locating loss
- F17D5/06—Preventing, monitoring, or locating loss using electric or acoustic means
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Electrochemistry (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Pathology (AREA)
- Acoustics & Sound (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
The invention discloses an anti-interference pulsed eddy current testing method. A probe without a shielding case is used for testing a tested pipeline having a distance with an adjacent pipeline, influence of each distance change on a testing voltage curve is compared, and the difference between the influence and the corresponding result of the probe with a shielding case is obtained; the difference between testing voltage curves of the probe with the shielding case is observed and calculated and used for determining the minimum pipeline distance under effective shielding of adjacent pipeline interference; a pipeline corrosion defect is selected from the tested pipeline, the influence of the metal shielding case on the defect testing sensitivity of the probe is evaluated, and whether the metal shielding case is qualified is determined. Influence of the adjacent pipeline can be inhibited by adding the metal shielding case to the testing probe. With adoption of the method, appropriate shielding parameters can be found through ordered tests.
Description
Technical field
The present invention relates to detection technique, particularly to a kind of pulse whirlpool with the interference of clad corrosive pipeline anti-adjacent pipeline
Stream detection method.
Background technology
Range with clad ferromagnetic pipeline is very wide, particularly very high in the industry utilization rate such as petrochemical industry.In pipeline
Portion often can be used for conveying high-pressure, high humidity and corrosive liquid gas medium, the rainwater outside pipe, and humid air etc. can cause corrosive pipeline.
For insulation and the purpose such as anti-corrosion, clad can be added outside pipe.It is non-conductive non-magnetic insulation that clad is close to pipeline
Material, thickness is tens to hundreds of millimeter, outermost layer be 0.5mm about aluminum skin or galvanized iron sheet.Remove clad to be corroded
Detection needs to stop work and cost is very high, therefore develops a kind of Pulsed eddy current testing technology in recent years, is not removing clad
Under conditions of corrosive pipeline is detected.
Abroad, RTD[1], Shell[2]Achieve good application result in company in this aspect.At home, Central China section
Skill university[3-5], Nanchang University of aviation[6-8]Non-Destructive Testing key lab has also actively developed studying and obtaining good of this aspect
Good effect.
In the middle of band clad pipeline Pulsed eddy current testing, there is a problem that tested pipeline is not often to isolate
Single pipe, but there is adjacent channel, be sometimes separated by also closer, thus detection can be impacted.
Content of the invention
The technical problem to be solved is, by phase in the middle of research band clad corrosive pipeline Pulsed eddy current testing
The size of adjacent pipeline impact, to suppress the shadow to detection for the adjacent channel using the method adding metallic shield in detection probe
Ring, and make detection probe detection sensitivity reduce less.
The present invention employs the following technical solutions and realizes above-mentioned purpose.Jamproof pulse eddy current detection method, tested pipeline
Side be provided with adjacent conduit, tested pipeline is enclosed with the clad with metal skin, and the clad with metal skin is provided with
Probe, probe is upper can to apply metallic shield, pop one's head in and be connected with pulse electromagnetic instrument, and pulse electromagnetic instrument is connected to powers for it
Battery, it comprises the following steps that：
1）First by probe, the tested pipeline having standoff distance with adjacent channel is detected, and each standoff distance is surveyed
Voltage in a coordinate system with abscissa as time, vertical coordinate draw out detection voltage curve for detection voltage, be respectively separated by
The impact to detection voltage curve for the distance change；
2）Probe applies metallic shield, constitutes band radome probe, according to step 1）Described in standoff distance, to tested
Pipeline is detected, draw one group of detection voltage curve, and with step 1）In detection voltage curve be compared；
3）Observation of steps 2）The middle detection voltage curve with radome probe, if step 2）Each standoff distance detection voltage bent
Difference between line is less than step 1）In difference between corresponding each standoff distance detection voltage curve, then metallic shield
There is shielding action to adjacent channel；Then the relative difference between the detection voltage curve calculated curve popped one's head in radome, looks for
Go out the less curve of relative difference, for determining the minimum pipeline standoff distance of effective shielding adjacent tubes interference：First described
A setpoint distance is selected, the detection voltage that corresponding pipeline standoff distance is more than with this setpoint distance is bent in the range of standoff distance
Line, calculates the relative difference between this group detection voltage curve；If this relative difference is less than poor between the detection voltage curve setting
Value percentage threshold, then record the minimum pipeline standoff distance that this setpoint distance is effectively shielding adjacent tubes interference, referred to as
Little effective screening range；If this minimum effectively screening range is less than the interference shielding distance threshold setting, then carry out step
4）；If this minimum effectively screening range is more than the interference shielding distance threshold setting, to this metal with radome probe
Radome parameter be modified after again from step 2）Proceed by test；
4）The impact to probe flaw detection sensitivity for the assessment metallic shield；
5）Choose pipeline corrosion default on tested pipeline, calculate and no shield under each standoff distance between adjacent channel and tested pipeline
Cover the detection sensitivity to this pipeline corrosion default for the cover probe；
6）Calculate under each standoff distance between adjacent channel and tested pipeline, pop one's head in described pipeline corrosion default with radome
Detection sensitivity；
7）By step 5）With step 6）In probe detection sensitivity be compared, if band radome probe with Without Shielding Cover visit
The detection sensitivity of head declines percentage ratio and is less than the probe detection sensitivity decline percentage threshold setting, then this band radome is visited
The design of head completes；After otherwise this metallic shield parameter with radome probe being modified, again from step 2）Start
Tested.
Preferably, described standoff distance span is 0.2-1.5m.
Preferably, described metallic shield parameter includes the pcrmeability of ferrimagnet and the electrical conductivity of metallic shield,
And the physical dimension of radome.
Preferably, described clad is to be close to pipeline and the non-conductive non-magnetic insulation material for 50-250mm for the thickness,
Outermost layer wraps up aluminum skin or the galvanized iron sheet of 0.3-1.0mm.
Preferably, described setpoint distance span is 0.2-1.5m.
Preferably, described relative difference is defined as one group of voltage curve in the maximum voltage value of synchronization point and minimum electricity
The percentage ratio that the difference of pressure value is drawn divided by maximum voltage value.
Preferably, between described detection voltage curve, difference percentage threshold span is 0-3%.
Preferably, described interference shielding distance threshold span is 0.2-1.5m.
Preferably, described probe detection sensitivity declines percentage threshold span is 0-30%.
Preferably, described pipeline corrosion default is the averagely thinning 5-35% of pipeline wall thickness and length is lacking of 100-200mm
Fall into.
Advantages of the present invention or beneficial effect are：When using Pulsed eddy current testing technology under conditions of not removing clad
During the corrosion of detection band clad pipeline, if there are other pipelines near tested pipeline, detection will be impacted.Pass through
The method adding metallic shield in detection probe, can suppress the impact of adjacent channel, effectively reduce impact distance.Detection spirit
Although sensitivity has declined, within the acceptable range.Especially under interference pipe uneven situation with tested pipe it is impossible to
Enough method elimination interference passed through parallel to conduit axis movement, then apply radome, sacrifice certain detection sensitivity and exchange for
Weakening or even eliminating of interference also just becomes rational selection.Using the method for the present invention by orderly test it is possible to look for
To suitable shielding parameter.
Brief description
Fig. 1 is the Pulsed Eddy Current Testing System schematic diagram of the test of the present invention；
Fig. 2 is the Without Shielding Cover probe detection voltage curve chart of the present invention；
Fig. 3 is the band radome probe detection voltage curve chart of the present invention；
Fig. 4 is Without Shielding Cover probe detection sensitivity curve chart；
Fig. 5 is the band radome probe detection sensitivity curve chart of the present invention.
Specific embodiment
Below in conjunction with drawings and Examples, the invention will be further described.
Referring to Fig. 1, the side of tested pipeline 1 is provided with adjacent channel 2, and tested pipeline 1 is enclosed with the cladding with metal skin
Layer 4, the clad 4 with metal skin is provided with the probe 3 of metallic shield, and probe 3 electric wires are connected with pulse electromagnetic instrument 6,
Battery 5 is connected to pulse electromagnetic instrument 6 and powers for it.
First Without Shielding Cover probe is arranged on the clad 4 on tested pipeline 1, tested pipeline 1 is detected.Phase
Adjacent pipeline 2 and tested pipeline 1 have certain standoff distance, and standoff distance takes a series of values as needed, such as 0.2m, 0.3m, 0.6,
0.8m, 1.0m, 1.2m, 1.5m etc..By each standoff distance record voltage in a coordinate system with abscissa as time, vertical coordinate be inspection
Survey voltage and draw out detection voltage curve.Each standoff distance obtains a detection voltage curve, so obtains one group of detection electricity
Buckle line.The relatively impact to detection voltage curve for the standoff distance change.
Be then used by carry radome probe, according to Without Shielding Cover pop one's head in identical standoff distance, tested pipeline 1 is carried out
Detection, draws one group of detection voltage curve, and is compared with the detection voltage curve of Without Shielding Cover probe.
The detection voltage curve of observation band radome probe, if between this probe each standoff distance detection voltage curve
Difference is less than the difference between the Without Shielding Cover corresponding each standoff distance detection voltage curve of probe, then metallic shield for
The impact of adjacent channel has shielding action.
Then the relative difference between the detection voltage curve calculated curve popped one's head in radome, finds out relative difference less
Curve, for determining the minimum pipeline standoff distance of effective shielding adjacent tubes interference：First in the range of described standoff distance
Select a setpoint distance, corresponding pipeline standoff distance is more than to the detection voltage curve of this setpoint distance, calculates this group
Relative difference between detection voltage curve；If this relative difference is less than difference percentage ratio threshold between the detection voltage curve setting
Value, then record the minimum pipeline standoff distance that this setpoint distance is effectively shielding adjacent tubes interference, referred to as minimum effectively shields
Distance；If this minimum effectively screening range is less than the interference shielding distance threshold setting, next step then can be carried out, assessment
The impact to probe flaw detection sensitivity for the metallic shield, otherwise tackles this metallic shield parameter with radome probe and enters
Row change after, again according to Without Shielding Cover pop one's head in identical standoff distance, tested pipeline 1 is detected, draw detection electricity
Buckle line, and be compared with the detection voltage curve of Without Shielding Cover probe, followed by relative difference calculate and look for
The step going out minimum effectively screening range, until minimum effectively screening range is less than the interference shielding distance threshold setting, then enters
Row next step, the impact to probe flaw detection sensitivity for the assessment metallic shield.
Assessment metallic shield to the method for impact of probe flaw detection sensitivity is：Pipe is chosen on tested pipeline 1
Road corrosion default, calculates Without Shielding Cover probe under each standoff distance between adjacent channel 2 and tested pipeline 1 and this corrosive pipeline is lacked
Sunken detection sensitivity；Then calculate each standoff distance lower band radome between adjacent channel 2 and tested pipeline 1 to pop one's head in described
The detection sensitivity of pipeline corrosion default；Detection sensitivity with radome probe and Without Shielding Cover probe is compared, such as
With radome probe, detection sensitivity compared with Without Shielding Cover probe declines percentage ratio less than the probe detection sensitivity setting to fruit
Decline percentage threshold, then this design with radome probe completes；Otherwise to this metallic shield ginseng with radome probe
Number be modified after, again according to Without Shielding Cover pop one's head in identical standoff distance, tested pipeline 1 is detected, draw inspection
Survey voltage curve, and carry out that all steps walk until this with upper described identical thereafter, then judge whether again to meet to set
Count into condition.
When Fig. 2 is that the present invention uses Without Shielding Cover probe, under adjacent channel 2 and tested pipeline 1 different spacing, obtained
One group of detection voltage curve chart.
When Fig. 3 is that the present invention is popped one's head in using band radome, under adjacent channel 2 and tested pipeline 1 different spacing, obtained
One group of detection voltage curve chart.
When Fig. 4 is that the present invention uses Without Shielding Cover probe, under adjacent channel 2 and tested pipeline 1 different spacing, to tested
The detection sensitivity curve chart of artificial nest corrosion default on pipeline 1.
When Fig. 5 is that the present invention is popped one's head in using band radome, under adjacent channel 2 and tested pipeline 1 different spacing, to tested
The detection sensitivity curve chart of artificial nest corrosion default on pipeline 1.
Embodiment:It is exemplified below the present invention one and be preferably embodied as case：
1）Using the detecting system shown in Fig. 1, the length of the tested pipeline 1 being used is 6000mm, nominal dimension φ 139.7 ×
Artificial nest corrosion default is processed on 7.72 J55 pipeline, wall thickness reduction is 32%, length 150mm.Adjacent channel 2 is same control gauge
The pipeline of the undressed artificial defect of lattice.
2）Probe 3 in Fig. 1 Pulsed Eddy Current Testing System specification in an embodiment（As shown in table 1）, swashing in probe
Encourage coil and signal receiving coil is coaxial, all using circular coil, loop structure is as given in table 1.
It is made up of dual shield cover in the present embodiment with the used metallic shield of radome probe.First is cup again
Shape structure, wall of cup is thick to be 1mm, and by probe placement wherein, cup-shaped structure is placed in the aluminum epidermis face of metallic shield.Second weight
For galvanized iron skin structure, the galvanized iron sheet using 0.5mm thickness makes, and overlaps 3 layers altogether.
The driving source of pulse electromagnetic instrument 6 uses positive negative bipolar pulse square wave electric current, and dutycycle is 1:1, driving frequency is
4Hz, size is 3.0A.Coating thickness is 110mm, is cladded with 0.5mm thickness aluminum skin.
3）When detecting tested pipeline 1, for the impact of detection probe 3 is put for observing adjacent channel 2 in periphery 1.5m
It is not added with radome in tested pipeline 1 near the side of adjacent conduit 2, be fixed on the position away from tested pipeline left end 1.2m,
Be respectively provided with horizontal range between tested pipeline 1 and adjacent conduit 2 be 1.5m, 1.0m, 0.8m, 0.6m, 0.4m, 0.3m,
0.2m, then enters row energization, and the reception sensor acquisition detection voltage from probe 3.In a coordinate system with abscissa as when
Between, vertical coordinate be detection voltage draw detection voltage curve such as Fig. 2.Be given in Fig. 2 is less than 0.8m pipeline standoff distance
The partial enlarged drawing of detection voltage curve.More than the detection electricity when detection voltage curve of 0.8m pipeline standoff distance and 0.8 meter
Pressure curve co-insides.
Figure it is seen that when probe 3 is without metallic shield, tested pipeline 1 and adjacent conduit 2 standoff distance exist
When between 0.8m to 0.3m, detection voltage curve is detached, illustrates that adjacent conduit 2 produces interference to the detection of tested pipeline 1,
And interference is gradually increased.Wherein, disturb between 0.3m to 0.2m and dramatically increase.
4）3 will be popped one's head in plus metallic shield, become band radome probe, be separated by according to Without Shielding Cover probe identical
Distance, detects to tested pipeline 1, draws one group of detection voltage curve, and the detection voltage curve with Without Shielding Cover probe
It is compared.
Relatively Fig. 3 and Fig. 2, is less than Without Shielding Cover in Fig. 2 with the difference that radome is popped one's head between detection voltage curve in Fig. 3
The difference popped one's head between the detection voltage curve of corresponding standoff distance, shows the impact for adjacent channel 2 for the metallic shield
There is shielding action, so that the change of detection voltage curve that the change of pipeline standoff distance causes reduces.
Then the relative difference between the detection voltage curve calculated curve with radome probe in Fig. 3, find out relative mistake
It is worth less curve, for determining the minimum pipeline standoff distance of effective shielding adjacent tubes interference.First in the phase gauge of experiment
From in the range of select a setpoint distance,（With reference to Fig. 3）It is 0.3m that curve difference situation selects setpoint distance, selectes detection electricity simultaneously
Difference percentage threshold between line of buckling is 3%.For the detection voltage curve of more than 0.3m in Fig. 3, i.e. the curve of 0.3-0.8m,
When taking same time point, ceiling voltage and minimum voltage difference are less than 3%, and therefore record 0.3m is effective shielding adjacent tubes interference
Minimum pipeline standoff distance, i.e. minimum effectively screening range.Then carry out next step, assessment metallic shield is to probe 3 inspection
Survey the impact of sensitivity.
5）The meaning of probe detection sensitivity is that the amplitude change that in the section curve of detection voltage curve, defect causes accounts for
The percentage ratio of background amplitude.It is described below about definition and computational methods：
When carrying out the detection of artificial nest corrosion default, pop one's head on clad along pipeline axial direction from one end of this defect
Move to the other end, select a test point to be detected, each test point obtains one in receiving coil at a certain distance
Individual detection voltage curve（Type is as shown in Fig. 2, Fig. 3）.
It is located at and detect altogether near artificial nest corrosion defaultMIndividual measuring point, and setNReceiving coil for each measuring point detects electricity
Buckle the sampling instant points of line, by window during each moment point referred to as, then theiThe detection data of individual measuring point can be expressed as
Vector：
(1)
AllMThe data of individual test point is write as matrix form：
(2)
In formula：WRepresent a matrix；MatrixWRow vector beV i ,i=1,…M,RepresentMIndividual measuring pointMBar detection voltage is bent
Line；Every row vectorV i ByNBeing total to of individual sampling instant pointNIndividual sampled value is constituted, and usesv ijRepresent,j=1,…N,ThejThe individual moment
Detection voltage value isv ij.
MatrixWColumn vector be then from the 1st point toMSensing corresponding in the synchronization of decline curve for the individual test point
Magnitude of voltage.With the coordinate of test point as abscissa, the curve drawn out for vertical coordinate with certain column vector is referred to as this column vector pair
Answer the detection voltage section curve figure of the workpiece in moment.If existing defects at certain measuring point, the detection voltage of certain column vector
On section curve figure, the inductive voltage value at this measuring point will appear from exception, thus showing to occur defect at this.
If the detection voltage curve of certain test point of pipeline window when certain（I.e. moment point）Voltage bev, its with intact
The voltage difference falling into window when locating corresponding is △v, here definition△v/vAs detection coil this when window detection sensitivity.△ v/vValue is bigger, illustrates that when this, window flaw detection sensitivity is higher.
In order to study the impact to detection sensitivity for this metallic shield, artificial pipe is chosen on the test specimen of tested pipeline 1
Road corrosion default is detected, calculates adjacent channel 2 unshielded under standoff distance 0.3m, 0.4m, 0.8m with tested pipeline 1
The detection sensitivity to defect for the cover probe, draws detection sensitivity curve chart（As shown in Figure 4）；Then calculate adjacent channel 2 with
Tested pipeline 1 detection spirit to described artificial nest corrosion default in standoff distance 0.3m, 0.4m, 0.8m lower band radome probe
Sensitivity, draws detection sensitivity curve chart（As shown in Figure 5）；Concurrently setting probe detection sensitivity decline percentage threshold is
15%；Fig. 5 is compared with Fig. 4, band radome probe detection sensitivity compared with Without Shielding Cover probe declines percentage ratio and is less than
15%, therefore this design with radome probe completes.
6）The discussion of the present invention：
After applying metallic shield, probe detection sensitivity can decline, and this is because radome also constitutes metal load in itself
A part, increases the load of probe.And flaw detection sensitivity reflection is the relative change loading.Load radix becomes big,
Therefore same corrosion default, because metal load radix becomes big after applying radome, relative variation reduces, and leads to detection spirit
Sensitivity can diminish.
Adjacent channel is also very common in production scene with the uneven situation of tested pipeline, at this time can not pass through parallel
Method in conduit axis movement eliminates adjacent channel interference, then apply radome, and the certain detection sensitivity of sacrifice exchanges for dry
Weakening or even eliminating of disturbing is a kind of rational selection.In addition, if probe is detected around pipeline movement, by relatively more all
To the difference of data to judge defect, then adjacent channel also constitutes and has a strong impact on.At this moment it is also required to apply radome, to the greatest extent
Pipe sensitivity decreases.
List of references：
[1]Breet C R, Raad J A. Validation of a pulsed eddy current system for
measuring wall thinning through insulation[J]. SPIE, 1996, 2947: 211-222.
[2]Crouzen P, Munns I. Pulsed Eddy Current Corrosion Monitoring in
Refineries and Oil Production Facilities –. Experience at Shell. ECNDT 2006.
[3] Wu Xinjun, Huang Chen, Ding Xu, etc. the development of steel corrosion Pulsed Eddy Current Testing System and application [J]. lossless inspection
Survey, 2010,32 (2): 127-130.
[4]Huang C, Wu X J, Xu Z Y, et al Pulsed eddy current signal processing
method for signal denoising in ferromagnetic plate testing[J]. NDT&E Int. ,
2010, 43: 648–653.
[5]Huang C, Wu X J, Xu Z Y, et al. Ferromagnetic material pulsed eddy
current testing signal modeling by equivalent multiple-coil-coupling approach
[J]. NDT&E Int. , 2011, 44: 163–168.
[6] Kang little Wei, Fu Yuewen. band clad ferromagnetic pipeline corrosion pulse eddy detection technology [J]. Non-Destructive Testing,
2011,33(9): 40-42.
[7] Fu Yuewen, Kang little Wei, explains star. with the Pulsed eddy current testing [J] of clad ferromagnetic metal pipeline local corrosion.
Application foundation and engineering science journal, 2013,21 (4): 786-795.
[8] Xue Shenglong, Fu Yuewen, Gu Zengtao. peripheral conduits are to the impact with clad pipeline Pulsed eddy current testing. lossless inspection
Survey, 2016,38 (3): 1-3.
Claims (10)
1. jamproof pulse eddy current detection method, the side of tested pipeline is provided with adjacent conduit, and tested pipeline is enclosed with band
The clad of metal skin, the clad with metal skin is provided with probe, and probe can apply metallic shield, probe and arteries and veins
Rush electromagnetic instrument to connect, pulse electromagnetic instrument is connected to the battery powered for it is characterised in that it comprises the following steps that：
1）First by probe, the tested pipeline having standoff distance with adjacent channel is detected, and each standoff distance is surveyed
Voltage in a coordinate system with abscissa as time, vertical coordinate draw out detection voltage curve for detection voltage, be respectively separated by
The impact to detection voltage curve for the distance change；
2）Probe applies metallic shield, constitutes band radome probe, according to step 1）Described in standoff distance, to tested
Pipeline is detected, draw one group of detection voltage curve, and with step 1）In detection voltage curve be compared；
3）Observation of steps 2）The middle detection voltage curve with radome probe, if step 2）Each standoff distance detection voltage bent
Difference between line is less than step 1）In difference between corresponding each standoff distance detection voltage curve, then metallic shield
There is shielding action to adjacent channel；Then the relative difference between the detection voltage curve calculated curve popped one's head in radome, looks for
Go out the less curve of relative difference, for determining the minimum pipeline standoff distance of effective shielding adjacent tubes interference：First described
A setpoint distance is selected, the detection voltage that corresponding pipeline standoff distance is more than with this setpoint distance is bent in the range of standoff distance
Line, calculates the relative difference between this group detection voltage curve；If this relative difference is less than poor between the detection voltage curve setting
Value percentage threshold, then record the minimum pipeline standoff distance that this setpoint distance is effectively shielding adjacent tubes interference, referred to as
Little effective screening range；If this minimum effectively screening range is less than the interference shielding distance threshold setting, then carry out step
4）；If this minimum effectively screening range is more than the interference shielding distance threshold setting, to this metal with radome probe
Radome parameter be modified after again from step 2）Proceed by test；
4）The impact to probe flaw detection sensitivity for the assessment metallic shield；
5）Choose pipeline corrosion default on tested pipeline, calculate and no shield under each standoff distance between adjacent channel and tested pipeline
Cover the detection sensitivity to this pipeline corrosion default for the cover probe；
6）Calculate under each standoff distance between adjacent channel and tested pipeline, pop one's head in described pipeline corrosion default with radome
Detection sensitivity；
7）By step 5）With step 6）In probe detection sensitivity be compared, if band radome probe with Without Shielding Cover visit
The detection sensitivity of head declines percentage ratio and is less than the probe detection sensitivity decline percentage threshold setting, then this band radome is visited
The design of head completes；After otherwise this metallic shield parameter with radome probe being modified, again from step 2）Start
Tested.
2. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described standoff distance value
Scope is 0.2-1.5m.
3. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described metallic shield is joined
Number includes the pcrmeability of ferrimagnet and the electrical conductivity of metallic shield, and the physical dimension of radome.
4. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described clad is to be close to
Pipeline and the non-conductive non-magnetic insulation material for 50-250mm for the thickness, outermost layer wraps up aluminum skin or the galvanized iron of 0.3-1.0mm
Skin.
5. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described setpoint distance value
Scope is 0.2-1.5m.
6. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described relative difference defines
Drawn divided by maximum voltage value in the maximum voltage value of synchronization point and the difference of minimum voltage value by one group of voltage curve
Percentage ratio.
7. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described detection voltage curve
Between difference percentage threshold span be 0-3%.
8. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described interference shielding distance
Threshold value span is 0.2-1.5m.
9. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that the detection of described probe is sensitive
It is 0-30% that degree declines percentage threshold span.
10. jamproof pulse eddy current detection method according to claim 1 is it is characterised in that described corrosive pipeline lacks
Fall into as the averagely thinning 5-35% of pipeline wall thickness and length is the defect of 100-200mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610995683.8A CN106404901B (en) | 2016-11-12 | 2016-11-12 | Jamproof pulse eddy current detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610995683.8A CN106404901B (en) | 2016-11-12 | 2016-11-12 | Jamproof pulse eddy current detection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106404901A true CN106404901A (en) | 2017-02-15 |
| CN106404901B CN106404901B (en) | 2019-04-09 |
Family
ID=59230213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610995683.8A Active CN106404901B (en) | 2016-11-12 | 2016-11-12 | Jamproof pulse eddy current detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106404901B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1719093A (en) * | 2004-07-09 | 2006-01-11 | 林俊明 | Method of detecting corrosion state of metal pipe line through insulating layer/cladding layer |
| JP2008241285A (en) * | 2007-03-26 | 2008-10-09 | Sumitomo Metal Ind Ltd | Eddy current flaw detection method and eddy current flaw detection device |
| CN202402950U (en) * | 2011-11-28 | 2012-08-29 | 周如斌 | Portable pipe corrosion and leakage on-site detecting device |
| CN102759567A (en) * | 2012-07-18 | 2012-10-31 | 南昌航空大学 | Eddy current testing recognition and evaluation method for defects of inner wall and outer wall of steel pipe under direct current magnetization |
| CN104820015A (en) * | 2015-05-08 | 2015-08-05 | 北京华航无线电测量研究所 | Detection system of metal surface defect and detection method thereof |
| CN105509631A (en) * | 2015-12-07 | 2016-04-20 | 天津因科新创科技有限公司 | Pulsed eddy current wall thickness detection method and device |
-
2016
- 2016-11-12 CN CN201610995683.8A patent/CN106404901B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1719093A (en) * | 2004-07-09 | 2006-01-11 | 林俊明 | Method of detecting corrosion state of metal pipe line through insulating layer/cladding layer |
| JP2008241285A (en) * | 2007-03-26 | 2008-10-09 | Sumitomo Metal Ind Ltd | Eddy current flaw detection method and eddy current flaw detection device |
| CN202402950U (en) * | 2011-11-28 | 2012-08-29 | 周如斌 | Portable pipe corrosion and leakage on-site detecting device |
| CN102759567A (en) * | 2012-07-18 | 2012-10-31 | 南昌航空大学 | Eddy current testing recognition and evaluation method for defects of inner wall and outer wall of steel pipe under direct current magnetization |
| CN104820015A (en) * | 2015-05-08 | 2015-08-05 | 北京华航无线电测量研究所 | Detection system of metal surface defect and detection method thereof |
| CN105509631A (en) * | 2015-12-07 | 2016-04-20 | 天津因科新创科技有限公司 | Pulsed eddy current wall thickness detection method and device |
Non-Patent Citations (3)
| Title |
|---|
| 付跃文 等: "带包覆层铁磁性金属管道局部腐蚀的脉冲涡流检测", 《应用基础与工程科学学报》 * |
| 武新军 等: "钢腐蚀脉冲涡流检测系统的研制与应用", 《无损检测》 * |
| 薛盛龙 等: "周边管道对带包覆层管道脉冲涡流检测的影响", 《无损检测》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106404901B (en) | 2019-04-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2017123261A1 (en) | Defect detector for conductive materials | |
| Chen et al. | Inversion method in pulsed eddy current testing for wall thickness of ferromagnetic pipes | |
| JP2005518534A (en) | Measuring the surface profile of an object | |
| CN104833720B (en) | The method of single coil electromagnetism Resonance detector metallic conduit damage | |
| US7106055B2 (en) | Fabrication of samples having predetermined material conditions | |
| Jarvis et al. | Performance evaluation of a magnetic field measurement NDE technique using a model assisted Probability of Detection framework | |
| CN107941904B (en) | Inspection probe and detection method in aerial metal path defective tube | |
| CN112229904A (en) | Pulse far-field eddy current detection probe and use method thereof | |
| Fan et al. | Research on crack monitoring technology of flexible eddy current array sensor based on TMR sensors | |
| Han et al. | Pulsed eddy currents in ferromagnetic pipes with cladding in nuclear power plants | |
| CN105403617B (en) | Band clad ferromagnetic pipeline corrosion detecting method | |
| CN117235433B (en) | Metal surface crack quantitative evaluation method based on alternating current magnetic field | |
| Yang et al. | A technology of full perimeter inspection for steel pipeline without removing cladding | |
| CN112415088A (en) | Inner-through transverse pulse eddy current detection probe and use method thereof | |
| Malikov et al. | Subminiature eddy-current transducers for conductive materials research | |
| Bian et al. | Crack identification and quantification methods under the condition of lift-off effect using alternating current field measurement technique | |
| CN106404901B (en) | Jamproof pulse eddy current detection method | |
| Hoek et al. | Localizing partial discharge in power transformers by combining acoustic and different electrical methods | |
| Krause et al. | Selecting the correct electromagnetic inspection technology | |
| Goldfine et al. | Introduction to the Meandering Winding Magnetometer (MWM) and the grid measurement approach | |
| US20190033258A1 (en) | Excitation and sensing systems and methods for detecting corrosion under insulation | |
| CN112347598B (en) | Double-covering-layer structure eddy current detection method | |
| CN211478151U (en) | Array probe for eddy current testing of curved surface workpiece | |
| CN112946065A (en) | Pulse eddy current detection method and device based on late signal slope | |
| KR102283396B1 (en) | Sensor Probe tesing System for Eddy Current Nondestructive Testing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |