CN2624208Y - Special-purpose probe for pipeline ultrasonic guided wave detecting and fixing apparatus therefor - Google Patents

Special-purpose probe for pipeline ultrasonic guided wave detecting and fixing apparatus therefor Download PDF

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Publication number
CN2624208Y
CN2624208Y CN 03246797 CN03246797U CN2624208Y CN 2624208 Y CN2624208 Y CN 2624208Y CN 03246797 CN03246797 CN 03246797 CN 03246797 U CN03246797 U CN 03246797U CN 2624208 Y CN2624208 Y CN 2624208Y
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China
Prior art keywords
probe
piezoelectric
guided wave
piezoelectric ceramics
pipeline
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Expired - Fee Related
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CN 03246797
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Chinese (zh)
Inventor
何存富
吴斌
于海群
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Beijing University of Technology
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Beijing University of Technology
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Abstract

The utility model discloses a special probe and the fixed device for pipeline ultrasonic guided wave testing, which is used for the position detesting of the defects of the pipeline in use. The utility model is characterized in that the fixed device of the probe is made into a ring shape; a plurality of grooves are arranged evenly around the direction of the circumference of the fixed device according to the size of the diameter of the probe fixed ring so as to store the single probe with the corresponding amount; the rear part of each probe groove is provide with a screwed hole; by putting the pressure on the single probe through a jbckscrew, each probe can be fixedly coupled on the pipeline; the utility model is provided with two probe fixed rings, and the two parts of the probe fixed rings are connected through a pin. When in use, by increasing the driving voltage on the probe, the ultrasonic guided wave for detecting the defects of the pipeline is produced in the pipeline spreading along the axial direction. The probe is composed of a piezoelectric component composed of a piezoelectric ceramics and a conducting electrode coated on the piezoelectric ceramics, a backing layer arranged on the piezoelectric ceramics and a protecting layer arranged below the piezoelectric ceramics. The utility model not only can conduct an effective position detesting to the defects of the pipeline, but also can be assembled and dismounted conveniently.

Description

The pipe ultrasonic guided wave detects dedicated probe and stationary installation thereof
Technical field:
The pipe ultrasonic guided wave detects dedicated probe and stationary installation thereof, the detection and localization of the defect of pipeline that is used for using, and this technology belongs to the Non-Destructive Testing field.
Background technology:
At present, the conventional method of pipeline Non-Destructive Testing mainly contains: ultrasonic, ray, magnetic, infiltration and eddy-current technique.But the harmless ultrasonic detecting technology of these routines all has its shortcoming that can't overcome, and for example: must pointwise detect, detection speed is slow, and must peel off surrounding layer etc.These shortcomings make these conventional sense may be used for the widely used up to ten thousand kilometers pipe detection of current industrial hardly.And the supersonic guide-wave technology can overcome these shortcomings to a great extent, and it comes down to a kind of line and detects, and can improve detection efficiency greatly; And not only can detect pipeline two surface imperfection, can also detect two surface imperfection.Have a lot of scholars to be devoted to study the excitation and the reception of guided wave both at home and abroad, the excitation of Lamb wave, cylinder guided wave and reception are wherein arranged, in pipeline excitation with receive the cylinder Lamb wave, in flat board, produce the Lamb wave of arrowband, single mode etc.
The probe of the most frequently used excitation and reception Lamb wave is based on the wedge pressure electroceramics probe of agreement principle.The agreement principle synoptic diagram as shown in Figure 1.Transmitting probe produces wavelength in couplant be λ cThe nominal plane ripple, the wavelength of then desiring field wave in plate is λ pc/ sin θ.Here λ c=c/f, λ p=c p/ f.C and c pBe respectively the phase velocity of the velocity of longitudinal wave and the Lamb wave of couplant, f is a stimulating frequency.Therefore can produce Lamb wave by changing incident angle with different frequency.As receiving this Lamb wave, receiving transducer is similar to transmitting probe, also will be positioned at same angle with respect to plate.
The excitation of cylinder guided wave and method of reseptance mainly contain probes such as electromagnetic sound, pulse laser formula and piezoelectric type.EMATS (electromagnetoacoustic probe) is used in the pipeline excitation by many researchers and receives the cylinder Lamb wave.The major advantage of EMATS is the untouchable of it, need not couplant, and this detection in the high-temperature pipe system is very important.EMATS both can produce the longitudinal ultrasonic guided wave easily in pipeline simultaneously, can produce circumferential supersonic guide-wave again.But EMATS has its shortcoming in essence:
1, EMATS needs high-intensity magnetic field to encourage.This makes the huge heaviness of experimental provision.Although along with this problem of appearance of powerful rare earth permanent magnet reduces to some extent.
2, the gap of EMATS and pipe surface requires accurately control.This gap has change big slightly, and its detection sensitivity sharply descends, even causes there is not received signal.
3, the output of EMATS is little more a lot of than the output of piezoelectric ceramics probe usually.
4, at the scene the experiment in, normally EMATS is connected with a motion motor (being called the machine of climbing).In the course of the work, this machine of climbing should move along pipeline, rotates around axis again.Probe must remain unchanged with the tube wall distance in motion process, otherwise can cause test data to be lost.And actual ducted irregular position is again unavoidable as concavo-convex place and connecting portion.This brings very big inconvenience to detection.
Scholar of the U.S. utilizes pulse laser matrix method excitation cylinder Lamb wave, has studied the energy distribution and the wave propagation velocity scattering problem of the excitation of Lamb wave and receiving efficiency, pattern, has provided the preliminary experiment result of pipelines defective.Because laser-ultrasound untouchable, this technology ought to obtain excellent research, but since huge, the costliness of this class device and technical sophistication also be not used widely so far.
The piezoelectric type probe is widely used with characteristics such as it are convenient, inexpensive, sensitivity is higher, technology is perfect.No matter be bulk wave, surface wave, or Lamb wave, utilize piezoelectric ceramics to pop one's head in encouraging and receive these ripples is modal methods.But the at present domestic ultrasonic guided wave detecting that does not also have special-purpose piezoelectric probe to be used for pipeline can only stick on piezoelectric chip on the pipeline, as shown in Figure 2.So not only waste time and energy, and the portability of this method and repeatable poor.For different pipelines, can only paste piezoelectric chip again, therefore can waste lot of manpower and material resources.
Technical scheme:
The objective of the invention is to develop a kind of piezoelectric probe and replace sticking on piezoelectric ceramics on the pipeline, and manufacture and design a kind of being used at the pipe surface static probe, make its mechanical hook-up that can be easy for installation and removal, and then defect of pipeline is carried out easily and effectively detection and location.
Technical scheme of the present invention is referring to Fig. 3-Fig. 6.The pipe ultrasonic guided wave detects dedicated probe in the technical design, includes piezoelectric element and equipped housing thereof, it is characterized in that described piezoelectric element is the piezoelectric ceramics of being made by retractable material 7, and the conductive electrode 6 that plates of lower surface constitutes thereon; Described probe 18 is by the piezo ceramic element 5 that is fitted in the housing, places back sheet 12 on the piezoelectric ceramics and places the protective seam 13 under the piezoelectric ceramics to constitute, and housing is provided with the link 9 of the contact conductor 11 of piezo ceramic element.
This pipe ultrasonic guided wave detects the piezoelectric element in the dedicated probe, what adopt is the piezoelectric ceramics that rectangular-shaped retractable material is made, the electrode of piezoelectric ceramics lower surface extends to upper surface through a side end, the lead-in wire of the electrode that plated of surface is free face unique from six faces of rectangular parallelepiped (referring among Fig. 6 shown in a 19) lead-in wire, and the concentric cable of setting is connected on this lead-in wire and the shell 10; And adopt epoxy resin to mix by known technology and solidify at normal temperatures and make the back sheet 12 that places on the piezoelectric ceramics with tungsten powder.
Be exclusively used in the stationary installation of pipe ultrasonic guided wave detection dedicated probe among the design, it is characterized in that, it mainly has probe set collar 14 attachable extending area, the annular casing shape by two in diametric(al) and constitutes, one of them probe set collar is provided with groove 15 in a circumferential direction, detects dedicated probe 18 with the disposed tubes pipeline ultrasonic guided wave, and each place to detect the dedicated probe groove the rear portion, process threaded hole and dispose and adopt conventional web member 17 to connect detecting between 16, two probes of conventional compacting part set collar that dedicated probe exerts pressure.And according to the size of selected probe set collar diameter, arrange evenly that at circumferencial direction plural at least pipe ultrasonic guided wave detects dedicated probe 18, form the piezoelectric ring of a separation.
Below in conjunction with accompanying drawing embodiment is elaborated.
Description of drawings:
Lamb wave excites and receives synoptic diagram in Fig. 1 prior art
1, transmitting probe, 2, accept probe, 3, steel plate;
Paste the synoptic diagram of piezoelectric ceramics in Fig. 2 prior art on the pipeline
4, experimental channel, 5, piezoelectric element;
Fig. 3 piezoelectric element synoptic diagram of the present invention
6, electrode, 7, piezoelectric ceramics;
Fig. 4 pipe ultrasonic guided wave of the present invention detects the dedicated probe structural representation
8, bonnet, 9, coaxial fitting, 10, shell, 11, piezoelectric ceramics lead-in wire 12, back sheet,
13, protective seam;
Fig. 5 probe fixing device structural representation of the present invention
14, transducer set collar, 15, the transducing tank, 16, jackscrew, 17, coupling arrangement;
The structural representation of Fig. 6 static probe on pipeline
18, supersonic guide-wave probe, 19, supersonic guide-wave unique free face signal of popping one's head in
Specific embodiments:
Design, assemble and debug with reference to Fig. 3-Fig. 5.Concrete consideration is as follows in the implementation process:
1, the pipe ultrasonic guided wave detects the design of dedicated probe.
For the development of single probe, consider mainly and adopt L (0, the 2) mode (a kind of longitudinal wave guide) of cylinder supersonic guide-wave to come pipeline is detected that because L (0,2) mode is axisymmetric, and its main components of strain are vertically.Therefore, in order to encourage and to receive L (0,2) modal waves, adopt a kind of piezoelectric ceramics of telescopic type to encourage and receive L (0,2) ripple, as shown in Figure 3.According to the layout in the practical application, after the overall dimensions of determining to pop one's head in, plate with electrode, and make the electrode of lower surface extend to upper surface through a side end so that lead-in wire connects in upper and lower surface.Again owing to need each probe is exerted pressure in actual applications, the lead-in wire of probe can not be from the top, can only be from six faces of piezoelectric ceramics rectangular parallelepiped unique free face (among Fig. 6 shown in 19) lead-in wire, for easy to use and attractive in appearance, adopt concentric cable to connect lead-in wire, in the free face of piezoelectric ceramics rectangular parallelepiped the junction block anchor leg is set, junction block is fixed at the inner nut that adopts of probe.
The intensity of piezoelectric ceramics is not high; bigger extruding or wearing and tearing may cause fracture; therefore the surface of contact at piezoelectric ceramics and pipeline must adopt protective seam; the requirement of protective seam is than higher; should protect piezoelectric ceramics not to be damaged, but also want transmitted acoustic pulse to greatest extent, make supersonic guide-wave loss therein as much as possible little; in order to reach this two requirements, the present invention adopts 100 microns to 200 microns iron plate or copper sheet to make protective seam.
Piezoelectric ceramics is at when vibration both direction radiative acoustic wave simultaneously forwards, backwards, but the sound wave of radiation can produce very adverse influence to the performance of probe backward, therefore will absorb this part sound wave with absorbent treatment.Absorbent treatment is to adopt epoxy resin to mix by known technology with tungsten powder, and is cured the back sheet of making 12 at normal temperature, can absorb the sound wave of radiation backward preferably.Because each probe need bear bigger pressure, therefore also need the bigger hard material of intensity and bear these pressure (among Fig. 4 shown in 8) at the probe rear portion.Sonde configuration as shown in Figure 4.
2, be exclusively used in the design that the pipe ultrasonic guided wave detects the dedicated probe stationary installation,
Usually if piezoelectric ceramics is bonded at pipeline external surface along the pipeline axial direction,, can not produce torsional mode in theory because piezoelectric element is flexible along the conduit axis direction.But because the asymmetry of driving source, then will produce two kinds of mode and be L (0, m) and F (n, m).If evenly arrange a series of piezoelectric ceramics at circumferencial direction, form the piezoelectric ring of a separation, then may offset asymmetrical model F (n, m).Therefore the probe of some need be set, they are fixed on around the pipeline equably.
Consider that the development probe system mainly is the defects detection that is used for column equipment such as pipeline, and probe system should be easy to installation and removal in testing process.The stationary installation of popping one's head among the present invention is done circlewise, and the groove that mills out some in a circumferential direction equably is to place single probe, the rear portion of each probe grooves processes threaded hole, utilize jackscrew that single probe is exerted pressure, thereby each probe can both be coupling on the pipeline securely; For the ease of probe system a dismounting can be installed easily, the probe set collar is divided into two parts along diametric(al), adopt pin to connect between two parts, as shown in Figure 5.
As shown in Figure 6, be provided with 24 pipe ultrasonic guided waves in the present embodiment and detect dedicated probe 18,24 rectangular channels 15 that evenly distribute around the ring of probe fixing device are placed probe, equally distributed 24 pressure that jackscrew 16 is produced around the ring of stationary installation upper edge are closely done coupling (centre does not add couplant) to 24 probes 18 on detected pipeline 4; Stationary installation is divided into two parts from the centre, is connected with pin-and-hole 16 by pin between two parts, applies driving voltage during use and can produce the supersonic guide-wave of propagating vertically on 24 probes in pipeline.

Claims (4)

1, a kind of pipe ultrasonic guided wave detects dedicated probe, include piezoelectric element and equipped housing thereof, of the present utility model being characterised in that, described piezoelectric element are the piezoelectric ceramics of being made by retractable material (7), and the conductive electrode (6) that plates of lower surface constitutes thereon; Described probe 18 is by the piezoelectricity piezoelectric element (5) that is fitted in the housing; place the back sheet (12) on the piezoelectric ceramics and place the protective seam (13) under the piezoelectric ceramics to constitute, housing is provided with the link (9) of the contact conductor (11) of piezo ceramic element.
2, pipe ultrasonic guided wave according to claim 1 detects dedicated probe, it is characterized in that, what adopt in the described piezoelectric element is the piezoelectric ceramics that rectangular-shaped retractable material is made, the electrode of piezoelectric ceramics lower surface extends to upper surface through a side end, the lead-in wire of the electrode that the surface is plated is free face (a 19) lead-in wire unique from six faces of rectangular parallelepiped, and this lead-in wire is gone up the concentric cable (9) that is provided with shell (10) and is connected; Adopt epoxy resin to mix by known technology and solidify to make at normal temperatures and place back sheet on the piezoelectric ceramics (12) with tungsten powder.
3, a kind of stationary installation that is exclusively used in pipe ultrasonic guided wave detection dedicated probe, it is characterized in that, it mainly has attachable extending area by two in diametric(al), the probe set collar (14) of annular casing shape constitutes, the probe set collar is provided with groove (15) in a circumferential direction, detect dedicated probe (18) with the disposed tubes pipeline ultrasonic guided wave, and place the rear portion of detecting the dedicated probe groove at each, process threaded hole and dispose, adopt conventional web member (17) to connect between two probe set collars detecting the conventional compacting part (16) that dedicated probe is exerted pressure.
4, a kind of stationary installation that the pipe ultrasonic guided wave detects dedicated probe that is exclusively used in according to claim 3, it is characterized in that, size according to selected probe set collar diameter, arrange evenly that at circumferencial direction plural at least pipe ultrasonic guided wave detects dedicated probe, form the piezoelectric ring of a separation.
CN 03246797 2003-04-25 2003-04-25 Special-purpose probe for pipeline ultrasonic guided wave detecting and fixing apparatus therefor Expired - Fee Related CN2624208Y (en)

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Application Number Priority Date Filing Date Title
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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101539540B (en) * 2009-04-09 2011-07-06 江苏省电力试验研究院有限公司 Ultrasonic guided wave testing method of corrosion of partially implanted pole body of steel pipe pole
CN102175773A (en) * 2010-12-24 2011-09-07 中国海洋石油总公司 Probe system for ultrasonic guided wave detection of marine pipeline and design method thereof
CN102565199A (en) * 2010-12-23 2012-07-11 中国石油天然气股份有限公司 Flexible probe ring for pipeline guided wave detection system
CN102854090A (en) * 2012-07-18 2013-01-02 北京工业大学 Detection device and method of liquid viscosity coefficient based on ultrasonic guided wave
CN102998372A (en) * 2012-12-04 2013-03-27 常州翰力信息科技有限公司 Fixing device of flaw detecting machine
CN103388378A (en) * 2013-07-31 2013-11-13 上海交通大学 Intelligent reinforcing steel bar based on piezoelectric ceramic crystal and fabrication method thereof
CN104749258A (en) * 2015-03-19 2015-07-01 暨南大学 Ultrasonic guided-wave probe array fixing device used for tube fitting detection
CN105021709A (en) * 2015-07-22 2015-11-04 杭州电子科技大学 Pipeline ultrasonic longitudinal guided wave flexible array detection probe apparatus
CN106153728A (en) * 2016-08-31 2016-11-23 中冶建筑研究总院有限公司 A kind of ultrasonic nondestructive testing device
CN106382473A (en) * 2016-09-28 2017-02-08 江苏省特种设备安全监督检验研究院 Rigid clamp for ultrasonic guided wave testing of various pipe diameters and use method
CN109239189A (en) * 2018-09-20 2019-01-18 河南理工大学 High-temperature pipe supersonic guide-wave based on functionally graded material monitors system and method

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101539540B (en) * 2009-04-09 2011-07-06 江苏省电力试验研究院有限公司 Ultrasonic guided wave testing method of corrosion of partially implanted pole body of steel pipe pole
CN102565199B (en) * 2010-12-23 2014-04-02 中国石油天然气股份有限公司 Flexible probe ring for pipeline guided wave detection system
CN102565199A (en) * 2010-12-23 2012-07-11 中国石油天然气股份有限公司 Flexible probe ring for pipeline guided wave detection system
CN102175773A (en) * 2010-12-24 2011-09-07 中国海洋石油总公司 Probe system for ultrasonic guided wave detection of marine pipeline and design method thereof
CN102854090B (en) * 2012-07-18 2015-03-04 北京工业大学 Detection device and method of liquid viscosity coefficient based on ultrasonic guided wave
CN102854090A (en) * 2012-07-18 2013-01-02 北京工业大学 Detection device and method of liquid viscosity coefficient based on ultrasonic guided wave
CN102998372A (en) * 2012-12-04 2013-03-27 常州翰力信息科技有限公司 Fixing device of flaw detecting machine
CN103388378A (en) * 2013-07-31 2013-11-13 上海交通大学 Intelligent reinforcing steel bar based on piezoelectric ceramic crystal and fabrication method thereof
CN103388378B (en) * 2013-07-31 2016-03-02 上海交通大学 Based on the intelligent reinforcing bar and preparation method thereof of piezoceramics crystal
CN104749258B (en) * 2015-03-19 2017-05-31 暨南大学 For the ultrasonic probe array fixing device of pipe fitting detection
CN104749258A (en) * 2015-03-19 2015-07-01 暨南大学 Ultrasonic guided-wave probe array fixing device used for tube fitting detection
CN105021709B (en) * 2015-07-22 2017-10-27 杭州电子科技大学 A kind of Pipes Using Ultrasonic Longitudinal Guided-Wave flexible array detection probe device
CN105021709A (en) * 2015-07-22 2015-11-04 杭州电子科技大学 Pipeline ultrasonic longitudinal guided wave flexible array detection probe apparatus
CN106153728A (en) * 2016-08-31 2016-11-23 中冶建筑研究总院有限公司 A kind of ultrasonic nondestructive testing device
CN106153728B (en) * 2016-08-31 2019-07-16 中冶建筑研究总院有限公司 A kind of ultrasonic nondestructive testing device
CN106382473A (en) * 2016-09-28 2017-02-08 江苏省特种设备安全监督检验研究院 Rigid clamp for ultrasonic guided wave testing of various pipe diameters and use method
CN106382473B (en) * 2016-09-28 2018-09-14 江苏省特种设备安全监督检验研究院 Rigid fixture and application method suitable for a variety of caliber ultrasonic guided wave detectings
CN109239189A (en) * 2018-09-20 2019-01-18 河南理工大学 High-temperature pipe supersonic guide-wave based on functionally graded material monitors system and method

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