CN109900807A - A kind of ultrasound positioning device of plastic conduit steel keel - Google Patents
A kind of ultrasound positioning device of plastic conduit steel keel Download PDFInfo
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- CN109900807A CN109900807A CN201910304788.8A CN201910304788A CN109900807A CN 109900807 A CN109900807 A CN 109900807A CN 201910304788 A CN201910304788 A CN 201910304788A CN 109900807 A CN109900807 A CN 109900807A
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- probe
- plastic conduit
- keel
- echo
- signal
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Abstract
The present invention discloses a kind of ultrasound positioning device of plastic conduit steel keel, including center processor, probe holder and the probe being mounted on probe holder, center processor and probe connect, probe holder is nested on plastic conduit to be detected, the netted keel structure of circumferential keel and axial keel composition is distributed in duct wall, the intersection of circumferential keel and axial keel forms pad, the quantity of the probe is 4, probe directly contacts always with plastic conduit, probe holder drives probe circumferentially for the helical movement, to which 4 echo-signals that probe receives feed back to center processor, 4 echo-signals include pure plastic pipe road echo-signal, plastic conduit and circumferential keel echo-signal, plastic conduit and axial keel echo-signal, plastic conduit and pad echo-signal, convenient for carrying out qualitative and quantitative analysis to its position deviation , realize that ultrasonic wave is accurately positioned the distribution of steel keel in the duct, structure is simple, easy to use, without destroying pipeline, save the cost.
Description
Technical field
The invention belongs to technical field of nondestructive testing, and in particular to a kind of localization by ultrasonic dress of plastic conduit steel keel
It sets.
Background technique
As shown in Figs. 1-2, steel keel plastic conduit be mainly used for liquid conveying, 150 millimeters -500 millimeters of outer diameter,
16 millimeters of wall thickness, the netted keel structure of circumferential keel and axial keel composition, circumferential keel and axial dragon are distributed in duct wall
The intersection of bone forms pad, and circumferential steel keel diameter is 3 millimeters, and axial steel keel diameter is 2 millimeters, circumferential direction and axis
It is 10 millimeters to the spacing distance of keel, if plastic conduit center is deviateed in the steel keel position of pipeline in process of production
The distance of position reaches 1/10th of pipe thickness or more, and the bearing capacity of plastic conduit will weaken significantly, is bearing centainly
When pressure, less serious case's pipeline deformation of cylindrical, severe one pipeline local fracture.Thus, it in process of production must be to steel dragon in pipeline
The position of bone sets carry out real-time monitoring, to ensure plastic conduit produced in use without security risk.Currently, the product from
Development stage starts always using the method for inspection of most original-sawing sampling observation method.Certain amount pipe is randomly selected from product
Road, radially cutting pipeline with a chainsaw is made with observing with whether the position deviation of steel keel in hand dipping section meets safety
With requiring.The method of inspection has certain effect to the position deviation measurement of steel keel in production process, but plastic conduit passes through
After multiple sawing can not normal use again, cause very big waste.Therefore, it (is taken out although being strict in process of production
Inspection rate 1% or so), but still regular generation pipe deforming, the major qualities accident such as burst apart in use, it absolutely proves
Sawing sampling observation method used at present fails to judge due to existing and brings serious security risk.
Summary of the invention
The purpose of the present invention is propose a kind of surpassing for plastic conduit steel keel for deficiency existing for existing detection technique
Acoustic fix ranging device realizes that ultrasonic wave is accurately positioned the distribution of steel keel in the duct, and structure is simple, convenient and efficient, without broken
Bad pipeline, save the cost.
To achieve the goals above, technical scheme is as follows:
A kind of ultrasound positioning device of plastic conduit steel keel, including center processor, probe holder and it is mounted on probe
Probe on frame, probe holder are nested on plastic conduit to be detected, and center processor and probe connect, it is characterised in that: institute
The quantity for stating probe is 4, and 4 probes directly contact always with plastic conduit, and probe holder drives probe circumferentially to make spiral fortune
Dynamic, so that receive 4 echo-signals are fed back to center processor by probe, 4 echo-signals include that pure plastic pipe road returns
Wave signal, plastic conduit and circumferential keel echo-signal, plastic conduit and axial keel echo-signal, plastic conduit and pad
Echo-signal.
Elastic telescopic part is equipped between the probe holder and probe, one end of elastic telescopic part is fixed on probe holder,
The other end and probe of elastic telescopic part are fixed.
The probe holder is in circular ring shape.
It is in 90 degree of phase differences between 4 probes, and is installed circumferentially on probe holder.
While the screw is that plastic conduit makees straight line traveling, probe holder drives probe along the circumferential direction to make just
To, reversely alternately 90 degree of helical scannings.
The probe uses 10 millimeters of wafer diameter, and set of frequency is the flat probe of 2MHz.
After adopting the above scheme, gain effect of the invention is:
1, ultrasound detection is radiationless to human body, easy to use, at low cost.
2, longitudinal wave pulse is issued by probe and carries out the distribution of reflection positioning steel keel in the duct, probe and plastic tube
Always directly the consistency of contact guarantee echo-signal, realization are accurately positioned in road, are made between probe and detected pipe surface
Distance makes corresponding adjustment with rough and uneven in surface surface appearance.
3, by the pure plastic pipe road echo-signal measured, plastic conduit and circumferential keel echo-signal, plastic conduit with
Axial keel echo-signal, plastic conduit and pad echo-signal can obtain calculate relevant parameter, detection accuracy up to arrive ±
0.1 millimeter, fully meet the testing requirements of plastic conduit steel keel position deviation.
If 4, steel keel plastic conduit produces ten thousand metres daily, traditional sawing process presses 1% sampling observation amount, 50 yuan/meter meter
It calculates, position deviation measurement is carried out using ultrasonic method, 5000 yuan can be saved daily, 1,800,000 yuan can be saved every year, it is quite objective to have
Economic benefit and wide application scenarios.
Detailed description of the invention
Fig. 1 is steel keel distribution expanded schematic diagram of the present invention；
Fig. 2 is steel keel distribution schematic diagram in plastic conduit of the present invention；
Fig. 3 is positioning device working condition shaft side figure of the present invention；
Fig. 4 is positioning device working condition main view of the present invention；
Fig. 5 is that pure plastic pipe road echo signal diagram is measured in the embodiment of the present invention；
Fig. 6 is that plastic conduit and circumferential keel echo signal diagram are measured in the embodiment of the present invention；
Fig. 7 is that plastic conduit and axial keel echo signal diagram are measured in the embodiment of the present invention；
Fig. 8 is that plastic conduit and pad echo signal diagram are measured in the embodiment of the present invention.
Description of symbols:
Plastic conduit 1, axial keel 12, pad 13, positioning device 2, probe 21, probe holder 22, begins circumferential keel 11
Send out 3, inner wall of the pipe back waves 4 of wave, secondary inner wall of the pipe back wave 5, circumferential keel back wave 6, axial keel back wave
7。
Specific embodiment
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention without any creative labor, may be used also for those of ordinary skill in the art
To obtain other drawings based on these drawings.
A kind of ultrasound positioning device 2 of plastic conduit steel keel, including center processor, probe holder 22 and probe 21,
The quantity of probe 21 is 4, is separately mounted on probe holder 22, and probe holder 22 is in circular ring shape, can be with the shape of plastic conduit 1
It matches, is conveniently nested on plastic conduit 1 to be detected, center processor (not shown) is connect with probe 21, is such as schemed
Shown in 3-4.
4 probes 21 directly contact always with plastic conduit 1, and probe holder 22 drives probe 21 circumferentially for the helical movement,
While the screw is that plastic conduit 1 makees straight line traveling, probe holder 22 drives probe 21 along 1 circumference side of plastic conduit
To positive, reversely alternately 90 degree of screws, to realize the non-blind area helical scanning to plastic conduit 1.In the present embodiment,
60 mm/min of pipeline straight line travel speed, 15 revs/min of 22 rotation speed of probe holder.
Testing principle is exactly that each probe 21 had not only emitted initial signal but also received the echo reflected from detected pipeline 1
Signal, if ultrasonic wave encounters the interface of impedance different medium composition in communication process, it will generate reflection echo, be reflected back
The amplitude size of wave depends on the size that different medium constitutes interface, and reflection echo depends on relative to the time span of initial spike 3
Interface is constituted in the position being detected in pipeline in different medium.
In order to which the outer wall of plastic conduit 1, the probe holder 22 and spy are adjacent to when making to pop one's head in 21 in the detection process always
Elastic telescopic part (not shown) is equipped between first 21, for example spring, one end of spring are fixed on probe holder 22, spring
The other end and probe 21 are fixed, make that probe the distance between 21 and detected pipe surface with rough and uneven in surface surface appearance
Corresponding adjustment, guarantees the consistency of echo-signal.
In order to solve the problems, such as the winding of probe signal line in 21 rotary courses of probe, 4 probes 21 are in 90 degree of phase difference peaces
On annulus probe holder 22,21 need of such 4 probes are along the circumferential direction positive, reversed 90 degree of alternate rotation can be completed pair
Scanning is completely covered in 1 surface of plastic conduit.
It pops one's head in 21 used in the ultrasound detection, is to realize transducing that electric energy, sound can be converted using the piezoelectric effect of material
Device.Critical component in probe 21 is chip, and chip is a monocrystalline or polycrystal thin slice with piezoelectric effect, its work
With being that can convert electric energy harmony mutually.Further, the probe 21 can be used 10 millimeters of wafer diameter, and set of frequency is
The flat probe 21 of 2MHz is easily obtained, is easy to implement.The positioning device 2 further includes the power supply for whole device power supply.
A kind of ultrasound locating method of plastic conduit steel keel, according to the difference of coupled modes, with water in the present embodiment
It is coupled for couplant, specific steps include:
Prepare before S1 helical scanning: probe holder 22 is inserted in, power supply is opened using water as couplant from 1 outer surface of plastic conduit
It opens；
S2 helical scanning: plastic conduit 1 starts to make straight line traveling, meanwhile, probe holder 22 drives probe 21 along plastic conduit 1
Circumferencial direction makees positive, reversely alternately 90 degree of helical scannings, 21 transmitting longitudinal wave pulse of probe, and receive 4 echoes are believed
Center processor number is fed back to, 4 echo-signals are respectively as follows: 1 echo-signal of pure plastic pipe road, plastic conduit 1 and circumferential keel
12 echo-signal of 11 echo-signals, plastic conduit 1 and axial keel, plastic conduit 1 and 13 echo-signal of pad；
S3 qualitative and quantitative analysis: plastic conduit wall thickness d1, circumferential keel and pipeline outer wall distance d2, axial keel and pipe
The distance d3 of pipeline outer wall, plastic conduit and pad distance d4 can be determined according to the following formula:
D=t*v/2
In formula, t is the time span of echo-signal, and v is velocity of longitudinal wave, and 2700 meter per second of longitudinal wave average speed is in pipeline
Determine value, here is specifically to calculate:
(1) 1 echo-signal of pure plastic pipe road is located at circumferential and axial keel 11,12 formed reticular structures by probe 21
Intermediate gaps when the ultrasonic echo signal that obtains, as shown in Figure 5.It can be seen from the figure that waveform signal is mainly by originating
3, inner wall of the pipe back waves 4 of wave and secondary inner wall of the pipe back wave 5 composition.Wherein initial spike 3 is couplant water and pipe
The back wave at the formed interface of pipeline outer wall；Inner wall of the pipe back wave 4 is that ultrasonic signal travels to inner wall of the pipe for the first time
With the reflection echo at the formed interface of air；Secondary inner wall of the pipe back wave 5 is that an inner wall of the pipe back wave 4 encounters outside pipeline
Reflected second of the communication process in wall interface.Time span and one between initial spike 3 and an inner wall of the pipe back wave 4
Time span between secondary inner wall of the pipe back wave 4 and secondary inner wall of the pipe back wave 5 is equal, is all 11.85 microseconds, in conjunction with pipe
Bulk sound velocity is 2700 meter per seconds in road, and can calculate pipe thickness is 16.00 milli of d1=11.85*2.7/2=15.9975 ≈
Rice, the actual thickness of pipeline are 16 millimeters, and the error of the two is 0.0025 millimeter.
(2) plastic conduit 1 and circumferential 11 echo-signal of keel, by 21 centers of probe vertically with circumferential keel 11 when obtained
Ultrasonic echo signal, as shown in Figure 6.It can be seen from the figure that waveform signal mainly includes that initial spike 3, circumferential keel are anti-
6, inner wall of the pipe back waves 4 of ejected wave, secondary inner wall of the pipe back wave 5.Between initial spike 3 and circumferential keel back wave 6
Time span is 5.08 microseconds, and can calculate distance of the circumferential keel 11 apart from pipeline outer wall is d2=5.08*2.7/2=6.86
Millimeter.
(3) 12 echo-signal of plastic conduit 1 and axial keel, it is acquired when by 21 centers of probe perpendicular to axial keel 12
Ultrasonic echo signal, as shown in Figure 7.It can be seen from the figure that waveform signal mainly includes that initial spike 3, axial keel are anti-
7, inner wall of the pipe back waves 4 of ejected wave and secondary inner wall of the pipe back wave 5.Between initial spike 3 and axial keel back wave 7
Time span is 7.32 microseconds, can calculate distance d3=7.32*2.7/2=9.88 milli of the axial keel 12 apart from pipeline outer wall
Rice.
(4) plastic conduit 1 and 13 echo-signal of pad, by popping one's head in, 21 centers vertically intersect weldering with circumferential and axial keel
Acquired ultrasonic echo signal when contact 13, as shown in Figure 8.It can be seen from the figure that waveform signal mainly includes originating
Wave 3, circumferential keel back wave 6, axial 7, inner wall of the pipe back waves 4 of keel back wave and secondary inner wall of the pipe back wave 5.
Time span between initial spike 3 and circumferential keel back wave 6 is 4.96 microseconds, can calculate d2=4.96*2.7/2=6.70
Millimeter.Time span between initial spike 3 and axial keel back wave 7 is 7.32 microseconds, can calculate d3=7.32*2.7/2
=9.88 millimeters.The distance between circumferential keel 11 and axial keel 12 are d4=d3-d2=9.88-6.70=3.18 millimeters,
The diameter of circumferential keel 11 is 3 millimeters, and measurement error is 0.18 millimeter, meets ± 0.1 millimeter of required precision.
In detection process, if the position deviation of circumferential or axial keel 11,12 is more than duct thickness in plastic conduit
10% (for 16 millimeters of duct thickness, position deviation is more than 1.6 millimeters), that is, be judged to waste product.Simultaneously by 1 position of plastic conduit
Reference record gets off and feeds back controlling of production process part, so that operator adjusts production technology in time to guarantee pipeline
The qualification rate of production.
Prepare also to need to proofread each probe 21 consistency to guarantee echo-signal before S1 helical scanning.
Basic principles and main features and advantages of the present invention of the invention have been shown and described above.The skill of the industry
Art personnel it should be appreciated that the present invention is not limited to the above embodiments, the above embodiments and description only describe
The principle of the present invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these
Changes and improvements all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and
Its equivalent thereof.
Claims (6)
1. a kind of ultrasound positioning device of plastic conduit steel keel, including center processor, probe holder and it is mounted on probe holder
On probe, probe holder is nested on plastic conduit to be detected, and center processor and probe connect, it is characterised in that: described
The quantity of probe is 4, and 4 probes directly contact always with plastic conduit, and probe holder drives probe circumferentially for the helical movement,
To which receive 4 echo-signals are fed back to center processor by probe, 4 echo-signals include pure plastic pipe road echo letter
Number, plastic conduit and circumferential keel echo-signal, plastic conduit and axial keel echo-signal, plastic conduit and pad echo
Signal.
2. a kind of ultrasound positioning device of plastic conduit steel keel according to claim 1, it is characterised in that: described
Elastic telescopic part is equipped between probe holder and probe, one end of elastic telescopic part is fixed on probe holder, elastic telescopic part it is another
One end and probe are fixed.
3. a kind of ultrasound positioning device of plastic conduit steel keel according to claim 1, it is characterised in that: described
Probe holder is in circular ring shape.
4. a kind of ultrasound positioning device of plastic conduit steel keel according to claim 1, it is characterised in that: described
It is in 90 degree of phase differences between 4 probes, and is installed circumferentially on probe holder.
5. a kind of ultrasound positioning device of plastic conduit steel keel according to claim 1, it is characterised in that: described
While screw is that plastic conduit makees straight line traveling, probe holder drives probe along the circumferential direction to make forward direction, reversely replace 90
Spend helical scanning.
6. a kind of ultrasound positioning device of plastic conduit steel keel according to claim 1, it is characterised in that: described
Probe uses 10 millimeters of wafer diameter, and set of frequency is the flat probe of 2MHz.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910304788.8A CN109900807A (en) | 2019-04-16 | 2019-04-16 | A kind of ultrasound positioning device of plastic conduit steel keel |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910304788.8A CN109900807A (en) | 2019-04-16 | 2019-04-16 | A kind of ultrasound positioning device of plastic conduit steel keel |
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| CN109900807A true CN109900807A (en) | 2019-06-18 |
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| CN201910304788.8A Pending CN109900807A (en) | 2019-04-16 | 2019-04-16 | A kind of ultrasound positioning device of plastic conduit steel keel |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113109675A (en) * | 2021-04-12 | 2021-07-13 | 西北核技术研究所 | Image diagnosis device and method for insulation stack vacuum surface flashover |
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Patent Citations (7)
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|---|---|---|---|---|
| JPS56122952A (en) * | 1980-02-29 | 1981-09-26 | Kawasaki Steel Corp | Rotatable defectoscope |
| CN1072372A (en) * | 1991-11-21 | 1993-05-26 | 张宝旺 | Reinforced formed plastic |
| EP0787294B1 (en) * | 1994-10-20 | 2002-04-10 | IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE | Inspection of pipes |
| US20160299106A1 (en) * | 2013-05-24 | 2016-10-13 | The Penn State Research Foundation | Systems and methods for using flexural modes in non-destructive testing and inspection |
| CN106442719A (en) * | 2016-11-17 | 2017-02-22 | 中国石油化工股份有限公司 | Pipeline bended waveguide detection method and system based on spiral comb type transducer |
| CN107462636A (en) * | 2017-07-18 | 2017-12-12 | 西安交通大学 | The self-centering supersonic array formula fixture and its application method of a kind of adjustable diameter |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113109675A (en) * | 2021-04-12 | 2021-07-13 | 西北核技术研究所 | Image diagnosis device and method for insulation stack vacuum surface flashover |
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Application publication date: 20190618 |