CN108259049A - The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization - Google Patents
The buried and underwater metallic conduit detectable signal emitter and its applying method of satellite synchronization Download PDFInfo
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- CN108259049A CN108259049A CN201810037958.6A CN201810037958A CN108259049A CN 108259049 A CN108259049 A CN 108259049A CN 201810037958 A CN201810037958 A CN 201810037958A CN 108259049 A CN108259049 A CN 108259049A
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- 238000000034 method Methods 0.000 title claims description 23
- 238000001514 detection method Methods 0.000 claims abstract description 69
- 230000001360 synchronised effect Effects 0.000 claims abstract description 23
- 239000002184 metal Substances 0.000 claims description 11
- 238000005259 measurement Methods 0.000 claims description 7
- 239000000523 sample Substances 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 abstract description 9
- 230000002787 reinforcement Effects 0.000 abstract 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract 1
- 239000007787 solid Substances 0.000 description 15
- 238000010586 diagram Methods 0.000 description 5
- 238000009933 burial Methods 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 229930183489 erectone Natural products 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/02—Transmitters
- H04B1/04—Circuits
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/185—Space-based or airborne stations; Stations for satellite systems
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- Geophysics And Detection Of Objects (AREA)
Abstract
The buried and underwater metallic conduit detectable signal emitter and detection method of satellite synchronization solve the problems, such as that great burying, long span are buried and pass through metallic conduit detectable signal because attenuation causes signal strength and transmission range that cannot meet detection and require under water.The emitter includes 4 solid-state relays in parallel again of connecting two-by-two of signal transmitter, control circuit and its control, and the intermediate node of two solid-state relays is drawn as two signal output ends, and a ground connection, one connects pipe under test.Output detectable signal stringent synchronization in sequential is realized by receiving GPS second pulse signal, two emitters is enable to realize fully synchronized superposition to the detection electric current that pipeline applies, reach the mutual reinforcement in transmission process of the detection electric current on pipeline, so as to increase the intensity of detectable signal, increase the effective detecting depth and distance to pipeline, so as to fulfill the detection purpose to great burying, long span crossing pipeline.
Description
Technical Field
The invention discloses a satellite synchronous detection pulse signal transmitting device, relates to superposition of large-buried-depth underground metal pipeline routing detection and buried-depth measurement signals, and belongs to the technical field of application of buried and underwater metal pipeline detection.
Background
The pipeline which is constructed by directional drilling and passes through and underwater passing pipelines of rivers, lakes and the like are in a special long-span large-burial depth environment, and detection current signals with enough strength need to be applied to the pipeline to be detected in the process of detecting the route and measuring the burial depth. If the buried and underwater crossing pipelines cannot be accurately positioned, other corrosion detections such as corrosion and protection conditions cannot be effectively implemented.
A general conventional terrestrial sounding signal application method is:
1. the earth pole method: and a signal transmitter is erected at one end of the pipeline, an output line at one end of the signal transmitter is connected with the pipeline, and the other output end of the signal transmitter is connected with the grounding electrode. The transmitted current signal forms a conductive loop transmission with the surface of the pipeline anticorrosion layer through the grounding electrode and the earth. The transmission distance and quality of the detection current signal are related to the resistance of a transmission loop determined by factors such as the conductivity degree of the soil environment, the insulating property and integrity degree of the outer anticorrosive layer of the pipeline and the like. When the conductivity of the soil is poor, the insulating property of the anticorrosive coating is poor and the integrity of the anticorrosive coating is low, the signal current which can be applied to the pipeline is small, and the transmission distance is short; otherwise, the signal transmission distance is far.
2. A loop connection method: in order to avoid environmental influence and improve the current intensity of detection signals, two ends of the pipeline are directly connected with the transmitter, so that the pipeline and the self output line of the transmitter form a power supply loop. If the anticorrosive coating is proper, the signal loss is little, and the signal intensity and the transmission distance can be greatly improved.
For underground and underwater pipelines penetrated by directional drilling, the transmission distance of the earth polar method is limited, and the environment condition of the loop connection method is limited; the superposition method by applying signals at both ends of the probe section respectively is an effective method to cope with the limitations of the two.
Disclosure of Invention
The invention aims to solve the problem that the signal strength and the transmission distance of a large buried depth and long span buried and underwater metal pipeline penetrating detection signal cannot meet the detection requirement due to attenuation, and provides a satellite synchronous buried and underwater metal pipeline detection signal transmitting device and an application method thereof. The invention is mainly applied to the route detection and the buried depth measurement of large buried depth, long span buried and underwater metal pipeline crossing.
Technical scheme of the invention
1. Satellite synchronous buried and underwater metal pipeline detection signal transmitting device
The transmitting device comprises a signal modulation unit, a control circuit and a satellite second pulse receiving unit. Two solid state relay branches are connected in parallel between two current signal output ends in a signal modulation unit, two solid state relays are respectively connected in series on each solid state relay branch, 4 solid state relays are counted, an intermediate node of the two solid state relay branches is led out to serve as two signal output ends, one solid state relay is grounded and is connected with a pipeline to be tested, the 4 solid state relays are controlled by a control circuit according to synchronous signals obtained by a satellite second pulse receiving unit connected with the control circuit, on-off control is carried out according to a set time sequence, and therefore modulation and emission of buried and underwater pipeline detection signals are achieved.
The specific implementation method of the transmitting device comprises the following steps:
1) the satellite second pulse receiving unit receives the second pulse signals broadcast by the satellite, so that the built-in clocks of the transmitters can be accurately calibrated, and the problem that current signals transmitted by two transmitters working at a long distance cannot be synchronized for a long time is solved. Two signal transmitting devices in satellite synchronization can transmit strictly synchronous detection signals for a long time, and the signal strength applied to the same target at the same time can realize synchronous superposition.
2) The control circuit with a microprocessor as a core modulates the current of a direct current power supply into a direct current pulse signal with a set frequency by controlling the orderly on-off of 4 solid-state relays, and applies the direct current pulse signal to the pipeline to be detected, thereby realizing the route detection and the buried depth measurement of the pipeline with large buried depth and long span.
3) The direct current pulse current signal with positive and negative half cycles which can be output simultaneously can eliminate the influence of the detection signal on the cathode protection polarization potential of the pipeline.
2. The method for applying the detection signal by using the detection signal transmitting device comprises the following steps:
1) the two ends of the pipeline to be detected are respectively provided with more than one detection signal transmitting device, one signal output end of each detection signal transmitting device is grounded, and the other signal output end of each detection signal transmitting device is connected to one end of the pipeline to be detected;
2) the two detection signal transmitting devices respectively receive the second pulse signals broadcasted by the satellite through the satellite second pulse receiving unit so as to accurately calibrate the built-in clock of the transmitting devices, avoid the problem that current signals transmitted by the two transmitting devices working at a long distance cannot be synchronized for a long time, and enable the two signal transmitting devices synchronized by the satellite to transmit strictly synchronized detection signals for a long time;
3) the precision of the satellite synchronous signal reaches 10-6And the detection is carried out in seconds, so that the current signals applied to the same target by the two transmitting devices at the same time can be strictly and synchronously superposed, the strength and the range of the detection signals are effectively increased, and the routing detection and the depth measurement of the large buried depth crossing pipeline are realized.
The detection principle and the calculation basis of the invention are as follows: based on satellite pulse-per-second signals, a control circuit with a microprocessor as a core modulates output current of a direct current power supply into direct current pulse signals with set frequency by controlling the orderly on-off of 4 solid-state relays, ensures that the signal output amplitude and direction are accurate and consistent at the same time, and realizes forward or reverse superposition under the combined action by a transmitter mounting mode.
Transmitter frequency and one wavelength time relationship:
f-frequency, in Hz;
t-wavelength time of one complete cycle, μ s.
In order to improve the sensing effect of the receiving unit on the signal and ensure the response time of triggering and switching off the solid-state relay, a certain interval delay is introduced between the positive half wave and the negative half wave of the signal, and the time length of the delay is determined by optimizing the receiving characteristic of the detection unit.
The invention has the advantages and beneficial effects that:
the invention is applied to the large buried depth burying and underwater crossing metal pipeline positioning and corrosion and protection detection engineering. Technical parameters of the probe include: routing and burial depth of the pipeline. When the pipeline is buried in large buried depth and long span and passes through underwater, if the signal applied by the earth polar method can not effectively cover half of the length of the detected pipeline, the detection tasks of all the pipeline sections of the detected pipeline can not be completed by respectively applying the signal at the two ends. The method of the invention is adopted to erect one transmitter at each of the test piles (or unearthed ends) at two ends of the detected pipeline, and simultaneously apply signals to the detected pipeline, and the effective detection range is 1.5-2.0 times of the sum of the effective detection ranges of the transmitters erected at two ends separately.
The invention can effectively improve the signal strength of the detection of the metal pipeline buried in the large buried depth and passing through the underwater, changes the prior signal applying mode, and realizes the route detection and buried depth measurement of the underwater passing through pipeline by a ground receiver or a detection device carried on an ROV (remote operated vehicle) of an underwater pipeline detection robot.
The invention integrates the signal modulation method, the calculation model, the application mode and other technologies. The technical method and the signal applying mode in the composition have the advantages of simple equipment structure, easy manufacture, convenient use, superposable detection signals, lengthened effective detection distance and the like. When signals are added at one end of the pipeline by the earth pole method, the signal quality does not meet the requirement of detecting the whole pipeline, but the effective detection distance is greater than 1/4-1/3 of the total length of the pipeline section, the transmitting device can be used for applying detection signals to the pipeline.
Drawings
Fig. 1 is a control structure diagram of a transmitting apparatus;
FIG. 2 is a control schematic of the launching device;
FIG. 3 is a timing diagram of a modulated pulse signal;
FIG. 4 is a schematic view of an ROV subsea pipeline survey;
FIG. 5 is a timing diagram of a 640Hz alternating pulse signal.
In the figure, 1 denotes a transmitting device, 2 denotes a satellite antenna, 3 denotes a crossing pipe, 4 denotes an underwater exploration device, 5 denotes a test pile, and 6 denotes an exploration work mother ship.
Fig. 2 is an implementation schematic diagram of fig. 1, in which only the connection mode of one solid-state relay is shown, and the other 3 connection modes are the same.
[ detailed description ] embodiments
1. Hardware implementation:
the satellite synchronous buried and underwater metal pipeline detection signal transmitting device comprises a signal modulation unit, a control circuit and a satellite second pulse receiving unit. Two solid state relay branches are connected in parallel between two current signal output ends in a signal modulation unit, two solid state relays are respectively connected in series on each solid state relay branch, 4 solid state relays are counted, an intermediate node of the two solid state relay branches is led out to serve as two signal output ends, one solid state relay is grounded and is connected with a pipeline to be tested, the 4 solid state relays are controlled by a control circuit according to synchronous signals obtained by a satellite second pulse receiving unit connected with the control circuit, on-off control is carried out according to a set time sequence, and therefore modulation and emission of buried and underwater pipeline detection signals are achieved. Wherein,
1) a power source. The external 12V-24V storage battery is adopted for power supply, and can be connected in series, and the maximum voltage is 96V.
2) Modulation of an alternating pulsed current signal. The transmitter circuit control schematic diagram (as shown in fig. 2), a second pulse receiving unit in the control circuit receives a second pulse signal through a satellite antenna, an internal clock of an MCU is calibrated at regular time, the MCU is switched on and off according to a set time sequence through a solid state relay control circuit, and input direct current is modulated into an alternating pulse signal (as shown in fig. 3).
2. The detection method comprises the following steps:
firstly, normally applying a signal to a pipeline by using a ground method at one end of the crossing pipeline, detecting the quality of the signal, and applying the signal by using the ground method by using the transmitting device of the invention if the signal coverage quality cannot meet the requirement of detecting the whole pipeline but the effective detection distance is greater than 1/4-1/3 of the whole length of the pipeline in a target area.
And secondly, respectively erecting a detection signal transmitting device at two ends of the pipeline to be detected by a ground method, connecting the positive and negative electrodes of the signal output ends of the two transmitting devices in a reverse connection mode, connecting the GPS antenna to the transmitting devices, starting the signal transmitting devices, selecting the same frequency, and outputting strictly synchronous detection signals to the pipeline by the transmitting devices after the second pulse receiving unit successfully searches for satellites so as to realize superposition of the signals transmitted at the two ends.
And thirdly, land detection, searching along the pipeline route, verifying the signal quality and implementing detection.
The detection method of the underwater crossing section is the same as that of the underwater crossing section: the positions of two signal points of the pipeline which can be applied are firstly determined on two banks on two sides, a pipe section between the two points is used as a target area, and an ROV is thrown into the target area for signal tracking and detection, so that the detection of the whole section of the crossing pipeline is completed (as shown in figure 4).
[ EXAMPLES ]
1. And (5) designing a time sequence. The frequency of the large buried depth detection signal is 640 Hz.
Calculating a time sequence: the frequency f of the detection signal is 640Hz, the time required by a complete signal is 1562.5 mus, and the half-wave time is 0.5t 781 mus. The trigger response time of the relay is 0.1 mus, and the corresponding time of the switch-off is 0.9 mus. Besides the response time of the solid-state relay is vacated, the signal sensing effect of the receiving unit is considered to be optimal, 480 mu s is selected to be on, and 301.25 mu s is selected to be off.
The specific control sequence is as follows: the positive half-wave is on 480 μ s → off 301.25 μ s → negative half-wave is on 480 μ s → off 301 μ s, completing one cycle. (FIG. 5)
2. And selecting components. The MCU control chip STM32F103CB, the GPS module and the antenna, an optical coupler TLP187 (transistor output optical coupler), an N-MOSFET-SKM180A020(MOSFET module) and an isolated power supply module DCP 021212. The power supply selects a 48V battery pack consisting of 12V series connection for power supply.
3. And (3) control program:
4. effects of the implementation
The transmitting device for satellite synchronous pipeline detection is successfully realized by applying the parameters. The device is characterized in that two transmitting devices are respectively erected at two ends of a pipeline to be detected by a ground pole method on two sides of a river with the width of about 700 meters, and the positive and negative poles of signal output ends of the two transmitting devices are reversely connected. The power is supplied by a 12V external storage battery, the actual emission result shows that the emission current of one is 2.34 amperes, the emission signal current of the other is 1.91 amperes, and the measured synchronous signal current on the pipeline is 1.77 amperes at the middle position of the river channel, so that the positioning detection and the buried depth measurement of the 17.5-meter deep pipeline are realized.
Claims (2)
1. A satellite synchronous buried and underwater metal pipeline detection signal transmitting device comprises a signal modulation unit, a control circuit and a satellite second pulse receiving unit; the system is characterized in that two solid-state relay branches are connected in parallel between two current signal output ends in a signal modulation unit, two solid-state relays are respectively connected in series on each solid-state relay branch, 4 solid-state relays are counted, a middle node of each solid-state relay branch is led out to serve as two signal output ends, one solid-state relay is grounded and the other solid-state relay is connected with a pipeline to be tested, and the 4 solid-state relays are controlled to be on and off by a control circuit according to a synchronous signal acquired by a satellite second pulse receiving unit connected with the control circuit.
2. A method for applying a probe signal using the probe signal transmitting apparatus according to claim 1, comprising the steps of:
1, erecting a detection signal transmitting device according to claim 1 at two ends of a pipeline to be detected respectively, wherein one signal output end of the detection signal transmitting device is grounded, and the other signal output end is connected to one end of the pipeline to be detected;
2, the two detection signal transmitting devices respectively receive the second pulse signals broadcasted by the satellite through the satellite second pulse receiving unit so as to accurately calibrate the built-in clock of the transmitting devices, avoid the problem that the current signals transmitted by the two transmitting devices working at a long distance cannot be synchronized for a long time, and enable the two signal transmitting devices synchronized by the satellite to transmit strictly synchronized detection signals for a long time;
3, the precision of the satellite synchronous signal reaches 10-6And the detection is carried out in seconds, so that the current signals applied to the same target by the two transmitting devices at the same time can be strictly and synchronously superposed, the strength and the range of the detection signals are effectively increased, and the routing detection and the depth measurement of the large buried depth crossing pipeline are realized.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114414461A (en) * | 2021-12-17 | 2022-04-29 | 中石化管道技术服务有限公司 | Protective potential satellite synchronous measurement device with positioning current pipeline and method |
| CN115166838A (en) * | 2022-09-07 | 2022-10-11 | 浙江图维科技股份有限公司 | Method and system for positioning pipeline |
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2018
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Patent Citations (6)
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114414461A (en) * | 2021-12-17 | 2022-04-29 | 中石化管道技术服务有限公司 | Protective potential satellite synchronous measurement device with positioning current pipeline and method |
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