CN1293366A - Equipment and method for detecting leakage of pipeline - Google Patents
Equipment and method for detecting leakage of pipeline Download PDFInfo
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- CN1293366A CN1293366A CN 00135740 CN00135740A CN1293366A CN 1293366 A CN1293366 A CN 1293366A CN 00135740 CN00135740 CN 00135740 CN 00135740 A CN00135740 A CN 00135740A CN 1293366 A CN1293366 A CN 1293366A
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Abstract
An equipment for detecting the defects, crack, leakage and structural characteristics of pipeline features that electromagnetic waves are radiated by emitting antenna in pipeline and receiver in pipeline can receive the electromagnetic waves containing reflected waves which can reflect the defects, crack, leakage and structural characteristics of pipeline. The received electromagnetic wave signals are processed to determine the defects, crack, leakage and structural characteristics of pipeline.
Description
The present invention relates to oil pipeline and storage industrial safety protection pick-up unit and method.
The medium of petrochemical enterprise pipeline transportation has explosive characteristics.In the pipeline operational process, reasons such as burn into artificially damages, disaster all can make the perforation of oil and gas pipes crack leak, and not only cause serious economy loss, and the harm ecologic environment, even the safety of life and property that jeopardizes the people.Find rapidly leakage accident and accurate location, in time adopting an effective measure, it is very important alleviating the harm that accident causes.Therefore, research pipe leakage fault real-time diagnosis technology has remarkable social benefit and economic benefit.All there is the function of Leak Detection and location in the SCADA system that is equipped with on external advanced person's the oil and gas pipes, and all is not equipped with this system on the most of pipelines of China.Introduce the investment of independent Leak Detection and Leakage Point Location System needs more than 1,000,000 yuan, as: the leak detection system of SSI company only software overhead just reaches 120,000 dollars.In addition, the gas oil pipe leakage of China detects and the leak source location also has its characteristics: 1. China's territorial environment and the climate change scenario complexity complicacy that increased pipe network makes that leak detection location technology difficulty is big; 2. external oil-piping leaks with natural cause such as corrosion or unexpected artificial damage in the majority, seeking leak source is easier to relatively, and that the gas oil pipe leakage of China is stolen with the offender is in the majority, and stolen (gas) point is difficult to find through camouflage, thereby the leak source locating accuracy is required high; 3. present leak source location technology needs power supply and signal transmission line, and this has not only increased the difficulty of implementing, the easier target that becomes offender's destruction.
The purpose of this invention is to provide the radiation in pipeline of a kind of application electromagnetic wave, utilize pipe crack, hole and pipeline configuration feature that the device and method that anti-leak detects is carried out in reflection of electromagnetic wave.
Pipeline protection leak detecting device of the present invention, it is characterized in that: it is by being fixed on the tested pipeline wall, and in it emitting antenna of radiated electromagnetic wave hold concurrently receiving antenna, the fundamental frequency electromagnetic wave that produces two kinds of patterns respectively with can carry out the pretreated Electromagnetic Launching of time tag identification and pattern-recognition and receiving trap, signal Processing and computer system to received signal, be connected the signal-transmitting cable of above-mentioned Electromagnetic Launching and receiving trap and signal Processing and computer system, the data communication antenna of switching computer deal with data is formed; Described signal-transmitting cable comprise receive carrying out of reflecting time tag identification and pattern-recognition pretreated electromagnetic wave signal Transmission Microwave band or waveguide, electromagnetic wave transmitter produce as the reference time delay reference coordinate of received signal and the transmission line of mode standard.
Aforesaid a kind of pipeline protection leak detecting device is characterized in that: Electromagnetic Launching and receiving trap can be made up of mode converter, microwave source, circulator, higher order filter, frequency discriminator, frequency division wave detector and data acquisition and signal processing circuit.
A kind of as mentioned above pipeline protection leak detecting device is characterized in that: the described emitting antenna receiving antenna of holding concurrently adopts circular volution form or rectangle volution form.
A kind of as mentioned above pipeline protection leak detecting device, it is characterized in that: described emitting antenna hold concurrently the receiving antenna optimum structure be the product of the pitch S of volution form and round diameter D or rectangle length of side D equal electromagnetic wavelength λ square take advantage of correction factor α, described correction factor value is 0.01-0.63.
A kind of as mentioned above pipeline protection leak detecting device is characterized in that: two cover antennas also can be installed, respectively separately as receiving and emitting antenna in the pipeline.
A kind of as mentioned above pipeline protection leakage detection method is characterized in that: utilize electromagnetic wave to transmit and receive device, transmit and receive reflected electromagnetic signal by waveguide-coupled to tested pipeline; By microwave source excitation TE and TM ripple,, the TE ripple is converted to high-order TE ripple earlier, is transmitted in the pipeline by antenna then by entering mode converter behind the circulator; Because the TE basic mode is extremely unstable in the pipeline, when crossing over crack or hole, produce new excitation electrical field, make original electric field deteriorate to high-order mode, in pipe crack and hole upstream and downstream, all be provided with receiving antenna, by to mistiming of reflection electromagnetic wave and launching electromagnetic wave with utilize the mensuration of the waveform pattern degeneration higher order mode of crack and hole reflection electromagnetic wave, detect breakage in the pipeline, break, the position and the size characteristic of leakage point.
Said a kind of pipeline protection leakage detection method is characterized in that: described launching electromagnetic wave and the continuous working of reception electromagnetic wave device, be not interrupted or alternation.
Aforesaid a kind of pipeline protection leakage detection method is characterized in that: emitter changes crack and the hole that emission wavelength is used to detect same order by some cycles.
Aforesaid a kind of pipeline protection leakage detection method is characterized in that: crack and hole reflection electromagnetic wave pattern feature satisfy the symmetrical dipole oscillation equation.
The present invention has following effect: using for reference modern antennas electricity mechanics of communication signal modulation principle aspect signals collecting and the data communication 1., the orientation of appropriate design sensor, particularly with the accent valve of pipeline operation and the training sample of transferring pump noise to discern as neural network, leakage signal as other class data-modulated recognition network input layer, thereby make diagnostic system handle the operating mode that minimal data detects pipeline in real time with extreme efficiency, detection speed is fast; 2. this invention is used for latest digital image processing techniques, artificial neural network and the pattern-recognition of modern computer application the detection of signal, utilize Wavelet Analysis Theory and signal correction theoretical analysis leakage signal and duct noise feature, improved the accuracy of identification of leakage signal; 3. the gas medium characteristic is less to the influence of electromagnetic field wave form varies, and particularly the pipe detection electromagnetism wave amplitude of long distance is penetrated control and modulated easily and realize.
The drawing explanation:
Fig. 1 is a principle schematic of the present invention.
Fig. 2 is the theory diagram that electromagnetic wave of the present invention receives transmitter.
Fig. 3 is that circular loop antenna of the present invention is surveyed view.
Fig. 4 is a circular loop antenna elevation cross-sectional view of the present invention.
Fig. 5 is a straight-flanked ring antenna side view of the present invention.
Fig. 6 is a straight-flanked ring antenna elevation cross-sectional view of the present invention.
Fig. 7 is the theory diagram of signal transmitting and receiving module of the present invention.
Fig. 8 is that antenna of the present invention is installed in the structural representation on the detected pipeline.
Fig. 9 is the application note figure of crack of the present invention principle.
The present invention has selected the metallic conduit of round section for use in the technological design of natural gas line and produced on-site, when the electromagnetic field of certain pattern during along the pipeline radiation, the electromagnetic wave signal that receives is just comprising the architectural feature of pipeline and the information of operating condition, particularly when pipeline has crack or hole, the reflection of electromagnetic waveform of AD HOC will be produced; When processing signals, will have the leakage signal data and send data processing equipment to carry out analyzing and processing; Utilize the relative theory of signal processing technology to obtain the amount of delay of signal, determine the leak position.Utilize recognition technology to judge leakiness; Show the degree of leakage and the particular location of leakage by the diagnosis report output system at last.
The present invention is made up of the hold concurrently emission of receiving antenna 2 and 3, electromagnetic wave and receiving trap 5 and 8, signal processing apparatus 6 and 9, data communication antenna 7 and 10, detection signal Computer Processing, demonstration and warning system 4 and 11, signal-transmitting cable 12 of electromagnetic wave emitting antenna.The fundamental frequency electromagnetic wave that is produced two kinds of patterns by electromagnetic wave transmitter 5 and 8 respectively is by antenna 2 and 3 radiation in detected pipeline, and the electromagnetic wave of radiation carries time tag forms certain pattern in pipeline waveguide coupler low order electromagnetic wave and propagates in pipeline 1.When the electromagnetic wave of this low step mode when pipe transmmision runs into pipe crack or hole, crack and hole just become the upstream and downstream reflection higher order mode electromagnetic wave of perturbation sky alignment pipe crack or hole.Receiving antenna 2 and 3 receives the electromagnetic wave that reflects, send electromagnetic receiving device 5 and 8 to carry out pre-service such as time tag identification and pattern-recognition through signal-transmitting cable 12, signal is delivered to signal processing apparatus 6 and 9, is sent to computer system 4 and 11 then and carries out analyzing and processing through signal-transmitting cable 12 after the pre-service, and the data after the processing are carried out relevant treatment by data communication antenna 7 and 10 swap datas again.The electromagnetic waves that produced by electromagnetic wave transmitter 5 and 8 are delivered to signal processing apparatus 6 and computer system 3 reference time delay reference coordinate and the mode standard as received signal through signal-transmitting cable; Computer system utilizes function program to carry out various related operations to received signal, and the result shows and report the position and the degree of detection pipeline operation situation, crack, hole.In said structure, antenna of the present invention is installed on the duct wall of detected piping system, as shown in Figure 6, its structural relation is: the 14th, and detected pipeline, the 15th, the standpipe that fixes up an aerial wire, the 16th, antenna, the 17th, standpipe sealing and antenna mount pad, the 18th, antenna IO interface, the 19th, fill insulant, the 20th, antenna module external diameter set collar.Install and on tube wall boring and machining screw be used to the assembly that fixes up an aerial wire, be processed with screw thread on the external diameter of antenna module and match with mounting hole on the duct wall, installing aft antenna is to place insides of pipes.Adopt microwave band or concentric cable to be used to transmit high-frequency microwave signal by antenna to the signal-transmitting cable that electromagnetic wave receives transmitter.Antenna adopts circular volution form and rectangle volution form.The structure of electromagnetic wave reception transmitter as shown in Figure 2.
The signal emission receives can adopt PCM-MH series, MRC series, AN/USM series or XCGX series, TY-QXD series integration module, and its schematic diagram signal is as follows:
As shown in Figure 5: earlier by microwave source excitation TE and TM ripple, by entering mode converter behind the circulator, the TE ripple is converted to high-order TE ripple, be transmitted in the pipeline by antenna then: because the TE basic mode is extremely unstable in the pipeline, when crossing over crack or hole, produce new excitation electrical field, and make original electric field deteriorate to high-order mode.This high-order mode electromagnetic field again from crack and hole to the pipeline internal reflection, in pipe crack and hole upstream and downstream pipeline, receiving antenna is arranged all, to carry out normalization, pattern demodulation, high-order filtering, phase compensation and amplitude folding by be sent to the Microwave Pretreatment device to pattern analysis, the conversion of reflection electromagnetic wave with after computing such as finding the solution, and delivers to the phase gain plug-in unit then and obtain amplitude output, phase place output and the output of pattern logarithm respectively; This three road signal is sent to data acquisition and data handling system is carried out analyzing and processing, has judged whether leakage, break slit and leak position.
The detection of crack principle is used as follows:
In radiotelegraphy, be used for effectively that the system of electromagnetic radiation wave energy is an electromagnetic radiation system, the system that is used for receiving effectively electromagnetic wave energy is the electromagnetism receiving system.And the system or the device that are used for radiation effectively and receive electromagnetic wave energy are antenna.In fact, antenna is a converter, it high-frequency current form (or guided wave form) on the contrary energy conversion be same frequency electromagnetic wave energy or.Therefore, utilize radiowave carry out work " in the electronic engineering (as communication, broadcasting, TV, radar, navigation etc.), antenna one of the visual plant that is absolutely necessary.Antenna of a great variety, the sorting technique of antenna differs.Can be divided into communication antenna, broadcast antenna, television antenna, radar antenna by purposes.Navigation antenna etc.: can be divided into long-wave antenna, medium-wave antenna, short-wave antenna by operation wavelength.Ultrashort wave antenna and microwave antenna etc.; Can be divided into emitting antenna by using method.Receiving antenna and duplexer etc.The research object of antenna is the irradiation of electromagnetic waves problem, and the external electromagnetic field that promptly researching antenna produced distributes.Adopt found the solution in the elementary current upper integral more in wire antenna, obtains currentless radiation field, utilizes superposition principle can separate the radiation field of continuous element (wire antenna) and discrete unit (array antenna) then.Another kind method is called vector potential method or auxiliary function method again.Promptly use vector potential (current potential and Hertz vector) to find the solution electromagnetic field as auxiliary function.In antenna, be to find the solution the bore diffraction problems mostly, often calculate with the Kirchhoff formula diffraction field.The Kirchhoff formula is the mathematic(al) representation of Huygens' principle, and it can obtain the electromagnetic field of the outer any point of sealing surface that surrounds radiation source.When operation wavelength is more much smaller than system linear size, also can adopt geometrical optics approach, according to laws of geometrical optics, promptly utilize ray to analyze electromagnetic wave propagation.
Leaky antenna is to have some cracks on waveguide or the resonator cavity to constitute.Because the crack cuts off the electric current line, make that waveguide or resonator cavity can radiation and reception electromagnetic waves.Usually adopt engineering approximation computing method, i.e. " dual character principle ".Leaky antenna on infinitely great current-carrying plate, the directional diagram that it produced is identical with the directional diagram with tabular oscillator identical with the crack mouth, and their difference is:
(1) electric field and magnetic field exchange;
(2) the field amount on leaky antenna sheet metal both sides is discontinuous, and its equal and opposite in direction, direction are opposite.
As shown in Figure 9:
By frequency is the desirable leaky antenna of the signal source feed of f=2k π, by the dual character principle as can be known, leaky antenna is in seam and the function of each point coordinate of spherical coordinates director space of electromagnetic field E, the H of surrounding space, and the direction with equivalent oscillator field intensity E, H is identical respectively.As in the medium of ε, μ, the reflection electromagnetic wave of crack and hole is not expressed as when having field source:
The feature that comprises pipe crack and hole in the formula has:
R is the distance apart from crack or hole center; This amount is used to measure crack and the hole length apart from antenna.
D is the width in crack;
I is the length in crack;
D1 represents the area in hole or crack;
Et is the intensity of electromagnetic wave when crossing over crack and hole in the pipeline.
The above-mentioned agenda of boundary condition one timing on the occluding surface that surrounds the volume of being discussed has monodrome and separates.According to following formula: can grow be 1, wide desirable leaky antenna for d is in the feature of the radiation field in far field.When receiving electromagnetic wave by discerning feature d and the L that amplitude mode just can the crack hole.
Its middle distance r utilizes formula r=CT to calculate, T be have identical time tag electromagnetic wave come and go antenna and crack time half.C is electromagnetic speed.
Claims (9)
1. pipeline protection leak detecting device, it is characterized in that: it is by being fixed on the tested pipeline wall, and in it emitting antenna of radiated electromagnetic wave hold concurrently receiving antenna, the fundamental frequency electromagnetic wave that produces two kinds of patterns respectively with can carry out the pretreated Electromagnetic Launching of time tag identification and pattern-recognition and receiving trap, signal Processing and computer system to received signal, be connected the signal-transmitting cable of above-mentioned Electromagnetic Launching and receiving trap and signal Processing and computer system, the data communication antenna of switching computer deal with data is formed; Described signal-transmitting cable comprise receive carrying out of reflecting time tag identification and pattern-recognition pretreated electromagnetic wave signal Transmission Microwave band or waveguide, electromagnetic wave transmitter produce as the reference time delay reference coordinate of received signal and the transmission line of mode standard.
2. a kind of pipeline protection leak detecting device as claimed in claim 1 is characterized in that: Electromagnetic Launching and receiving trap can be made up of mode converter, microwave source, circulator, higher order filter, frequency discriminator, frequency division wave detector and data acquisition and signal processing circuit.
3. a kind of pipeline protection leak detecting device as claimed in claim 1 is characterized in that: the described emitting antenna receiving antenna of holding concurrently adopts circular volution form or rectangle volution form.
4. a kind of pipeline protection leak detecting device as claimed in claim 1, it is characterized in that: described emitting antenna hold concurrently the receiving antenna optimum structure be the product of the pitch S of volution form and round diameter D or rectangle length of side D equal electromagnetic wavelength λ square take advantage of correction factor α, described correction factor value is 0.01-0.63.
5. as claim 1 or 3 described a kind of pipeline protection leak detecting devices, it is characterized in that: two cover antennas also can be installed, in the pipeline respectively separately as receiving and emitting antenna.
6. a pipeline protection leakage detection method is characterized in that: utilize electromagnetic wave to transmit and receive device, transmit and receive reflected electromagnetic signal by waveguide-coupled to tested pipeline; By microwave source excitation TE and TM ripple,, the TE ripple is converted to high-order TE ripple earlier, is transmitted in the pipeline by antenna then by entering mode converter behind the circulator; Because the TE basic mode is extremely unstable in the pipeline, when crossing over crack or hole, produce new excitation electrical field, make original electric field deteriorate to high-order mode, in pipe crack and hole upstream and downstream, all be provided with receiving antenna, by to mistiming of reflection electromagnetic wave and launching electromagnetic wave with utilize the mensuration of the waveform pattern degeneration higher order mode of crack and hole reflection electromagnetic wave, detect breakage in the pipeline, break, the position and the size characteristic of leakage point.
7. a kind of pipeline protection leakage detection method as claimed in claim 6 is characterized in that: described launching electromagnetic wave and the continuous working of reception electromagnetic wave device, be not interrupted or alternation.
8. a kind of pipeline protection leakage detection method as claimed in claim 6 is characterized in that: emitter changes crack and the hole that emission wavelength is used to detect same order by some cycles.
9. a kind of pipeline protection leakage detection method as claimed in claim 6 is characterized in that: crack and hole reflection electromagnetic wave pattern feature satisfy the symmetrical dipole oscillation equation.
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|---|---|---|---|
| CN 00135740 CN1293366A (en) | 2000-12-19 | 2000-12-19 | Equipment and method for detecting leakage of pipeline |
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| CN 00135740 CN1293366A (en) | 2000-12-19 | 2000-12-19 | Equipment and method for detecting leakage of pipeline |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100390531C (en) * | 2004-06-11 | 2008-05-28 | 清华大学 | Gas pipeline leakage detecting and positioning method and system based on microwave technology |
| US7921694B2 (en) | 2005-10-12 | 2011-04-12 | Airbus Deutschland Gmbh | Leak detector and detection method using radiation transmitted through a fluid line |
| CN104024721A (en) * | 2011-10-21 | 2014-09-03 | 气体运输技术公司 | Mobile support for examination of a wall |
| CN104574916A (en) * | 2014-01-27 | 2015-04-29 | 青岛雅合阴保工程技术有限公司 | Method and system for communicating by using submarine pipeline |
| CN105649617A (en) * | 2016-01-15 | 2016-06-08 | 中国石油大学(北京) | Experimental method for monitoring expansion process of hydraulic fracture through electromagnetic signals |
| CN107402233A (en) * | 2017-07-12 | 2017-11-28 | 温州职业技术学院 | A kind of Photoelectric Detection warning device of submarine pipeline |
| CN109580134A (en) * | 2018-11-21 | 2019-04-05 | 清华大学 | A kind of industrial environment method for detecting leakage and device based on double RFID label tags |
| CN111998234A (en) * | 2020-07-28 | 2020-11-27 | 宁波天木工程设计有限公司 | Automatic control system for corrosion prevention in land oil and gas pipeline |
| CN115183160A (en) * | 2022-07-22 | 2022-10-14 | 广东力创信息技术有限公司 | Method and equipment for reducing false alarm of pipeline leakage |
| CN115577736A (en) * | 2022-09-16 | 2023-01-06 | 北京燃气平谷有限公司 | Gas leakage evaluation system and leakage evaluation method |
-
2000
- 2000-12-19 CN CN 00135740 patent/CN1293366A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100390531C (en) * | 2004-06-11 | 2008-05-28 | 清华大学 | Gas pipeline leakage detecting and positioning method and system based on microwave technology |
| US7921694B2 (en) | 2005-10-12 | 2011-04-12 | Airbus Deutschland Gmbh | Leak detector and detection method using radiation transmitted through a fluid line |
| CN101283258B (en) * | 2005-10-12 | 2011-06-15 | 空中客车德国有限公司 | Leak detector |
| US8365581B2 (en) | 2005-10-12 | 2013-02-05 | Airbus Operations Gmbh | Valve for a leak detector |
| CN104024721A (en) * | 2011-10-21 | 2014-09-03 | 气体运输技术公司 | Mobile support for examination of a wall |
| CN104574916B (en) * | 2014-01-27 | 2018-10-12 | 青岛雅合科技发展有限公司 | The method and communication system communicated using submarine pipeline |
| CN104574916A (en) * | 2014-01-27 | 2015-04-29 | 青岛雅合阴保工程技术有限公司 | Method and system for communicating by using submarine pipeline |
| CN105649617A (en) * | 2016-01-15 | 2016-06-08 | 中国石油大学(北京) | Experimental method for monitoring expansion process of hydraulic fracture through electromagnetic signals |
| CN107402233A (en) * | 2017-07-12 | 2017-11-28 | 温州职业技术学院 | A kind of Photoelectric Detection warning device of submarine pipeline |
| CN107402233B (en) * | 2017-07-12 | 2024-03-05 | 温州职业技术学院 | Photoelectric detection alarm device for submarine pipeline |
| CN109580134A (en) * | 2018-11-21 | 2019-04-05 | 清华大学 | A kind of industrial environment method for detecting leakage and device based on double RFID label tags |
| CN111998234A (en) * | 2020-07-28 | 2020-11-27 | 宁波天木工程设计有限公司 | Automatic control system for corrosion prevention in land oil and gas pipeline |
| CN115183160A (en) * | 2022-07-22 | 2022-10-14 | 广东力创信息技术有限公司 | Method and equipment for reducing false alarm of pipeline leakage |
| CN115577736A (en) * | 2022-09-16 | 2023-01-06 | 北京燃气平谷有限公司 | Gas leakage evaluation system and leakage evaluation method |
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