CN114923641A - Pressure pipeline leakage detection device and using method - Google Patents

Abstract

The invention relates to a pressure pipeline leakage detection device and a use method thereof, wherein the device comprises an optical fiber sensor, the side wall of the pressure pipeline is provided with a round hole for the optical fiber sensor to enter and exit, and the round hole is provided with a sealing element for sealing a gap between the optical fiber sensor and the round hole; the optical fiber sensor comprises a sensing optical fiber and an optical fiber protection sleeve which completely wraps the sensing optical fiber, and a pressurizing cavity is arranged inside the optical fiber protection sleeve. The invention is suitable for leakage detection of pressure pipelines in the industries of water diversion, water supply, heat supply and the like, has good flexibility and good construction convenience, saves resources, saves energy, protects environment and saves the time required by emptying. The invention detects the sound vibration generated by the leakage of the pressure pipeline through the optical fiber sensor to search the leakage point and accurately position. Under the condition of no need of emptying, the pressure pipeline is perforated, and the optical fiber sensor is creatively placed in the pressure pipeline, so that the interference of the environmental background noise when the optical fiber sensor is used for leakage detection outside the pipeline is reduced to the maximum extent.

Description

Pressure pipeline leakage detection device and using method

Technical Field

The invention relates to a pressure pipeline leakage detection device and a using method thereof, and belongs to the technical field of pressure pipeline risk monitoring and early warning.

Background

The pressure pipeline leakage point inspection is an effective method for finding pipeline leakage and preventing pipe explosion, and has great significance for guaranteeing the safe operation of the pipeline and reducing the pipeline leakage rate. The pipeline comprises existing pressure pipelines in industries of water diversion and regulation, water supply, heat supply and the like. The existing detection instruments such as leakage listening instruments and correlation instruments utilize sound emitted by a sound sensor when the leakage is detected on the outer wall of a buried pressure pipeline or the road surface above the pipeline to search leakage points. Due to the background noise of the external environment, particularly the noise emitted by vehicles on the road, the detection accuracy and efficiency are seriously affected. In addition, because the buried pipeline is linear, the traditional sensors such as leak detector and correlation instrument are point type, the detection efficiency is low, and even if a certain section of pipeline has a leak point, the leak point can not be accurately positioned. The traditional leak detection method needs a large number of workers to detect leaks along roads at night, is dangerous and high in painstaking degree, also depends on the experience of the workers, and is low in leak detection accuracy.

The Chinese patent of invention "CN 105351756B-a pipeline leakage identification and positioning system and method based on acoustic imaging" the invention has the main technical characteristics that: the identification and positioning system comprises a pipeline infrasonic wave sensor, a digitizer, a direct current stabilized voltage supply and a monitoring server; the pipeline infrasonic wave sensors are respectively arranged at two ends of a pipeline to be detected, sensing heads of the pipeline infrasonic wave sensors are completely contacted with a medium in the pipeline through openings in the pipeline to be detected and immersed in the medium, and the pipeline infrasonic wave sensors transmit measurement signals to the monitoring server through a digitizer; and the monitoring server calculates an acoustic image of sound pressure distribution in the pipeline between the two pipeline infrasonic wave sensors according to the measurement signals uploaded by the two digitizers, and identifies the position and the intensity of the leakage sound source from the acoustic image. The invention utilizes the broadband characteristic of the leakage sound to identify the leakage from the stability of the sound image, improves the accuracy of the leakage identification, achieves the accuracy of more than 95 percent, has the false alarm rate of less than 5 percent, can reflect the leakage process and estimate the leakage flow.

The method is characterized in that holes are drilled at two ends of a pipeline, one sensor is respectively arranged in each hole, and the collected sound of a leakage point is transmitted to the two sensors through a medium in the pipeline.

The existence of noise emitted by a conveying medium and environmental background noise outside the pipeline in the pipeline conveying process brings great trouble to the analysis and processing of data by a comparison method, and in addition, the distance which can be detected by each section is very limited, the long-distance pipeline can only be divided into a plurality of sections for detection, otherwise, signals are attenuated continuously in the medium transmission process, and the accuracy of measurement is influenced finally. More importantly, if the length of the buried pipeline is greater than the maximum distance that the system can detect and locate, in the actual operation process, it is necessary to excavate one section by one section to expose the buried pipeline, and then open a hole to install a sensor, which is unrealistic and has great limitation, especially in some environments where excavation is not allowed. In addition, the sound sensor is positioned according to the time difference of sound transmitted to the two sensors through the pipeline medium, the transmission speed of the sound in the medium is unstable and closely related to the pressure, the temperature, the roughness of the inner wall of the pipeline and the viscosity of the medium, and if a leakage point is between the two sensors, a section of sound is inevitably transmitted to the upstream sensor in a countercurrent mode. Therefore, the calculated error of the position of the missing point is large and can not be checked again. In addition, if a leak detector is adopted to search for a leak point, detection is carried out when few vehicles are driven on the road at night, noise is reduced, and traffic stream avoiding personnel are safer and have larger limitation.

Disclosure of Invention

The invention provides a pressure pipeline leakage detection device and a using method thereof aiming at the defects in the prior art, and the specific technical scheme is as follows:

a pressure pipeline leakage detection device is used for detecting leakage of a pressure pipeline and comprises an optical fiber sensor, wherein a circular hole for the optical fiber sensor to enter and exit is formed in the side wall of the pressure pipeline, and a sealing element for sealing a gap between the optical fiber sensor and the circular hole is arranged at the position of the circular hole; the optical fiber sensor comprises sensing optical fibers and an optical fiber protection sleeve which completely wraps the sensing optical fibers, the head end of the optical fiber protection sleeve is closed, the tail end of the optical fiber protection sleeve is connected with the sensing optical fibers in a sealing mode, and a pressurizing cavity with air pressure larger than atmospheric pressure is formed in the optical fiber protection sleeve.

As an improvement of the above technical scheme, the sealing element includes an internal thread pipe, an elastic sealing ring located inside the internal thread pipe, a through stud in threaded connection with the internal thread pipe, and a circular ring-shaped baffle plate arranged outside the circular hole, the baffle plate is in sealed connection with the side wall of the pressure pipeline, the tail end of the internal thread pipe is in sealed connection with the baffle plate, the through stud, the elastic sealing ring and the baffle plate are all sleeved outside the optical fiber sensor, and the elastic sealing ring is located between the through stud and the baffle plate. The middle through stud is a stud with a hollow structure in the axial direction.

The lower part of the internal thread pipe is not provided with threads, the internal thread pipe is fully welded at the position of the baffle, the internal thread pipe is kept communicated with the pressure pipeline, and the baffle welded with the internal thread pipe is welded to a round hole formed in the pressure pipeline. And after the middle through stud is screwed into the internal thread pipe, the middle through stud extrudes the elastic sealing ring, so that the clearance fit between the elastic sealing ring and the optical fiber sensor is changed into interference fit, and the sealing between the optical fiber sensor and the internal thread pipe is finished.

As an improvement of the technical scheme, the tail end of the through stud is fixedly connected with a handle. The stud can be turned through the handle.

As an improvement of the technical scheme, a convex part is arranged at the tail end of the through stud, and the through stud and the convex part form a through bolt. Wherein, the well logical bolt is the bolt that the axial is hollow structure.

As an improvement of the technical scheme, the air pressure in the pressurizing cavity is 0.4-0.8 Mpa.

The utility model provides a pipeline under pressure device that leaks hunting, gathers the sound that pipeline under pressure leaked and sent through optical fiber sensor and seeks the leak source to through gathering the position that the leak source was come the preliminary definite pipeline under pressure leak source to the length that the sound that leaks is corresponding to on the sensing optical fiber, judge the actual position of leak source through strikeing ground in the leak source top: if the vibration signal sent out when the floor is knocked is behind the leakage point, the knocking position is moved forwards; if the knocking signal is in front of the leakage point signal, moving the knocking position backwards; and if the knocking signal and the leakage point signal are superposed, judging that the leakage point is just below the knocking part.

A use method of the pressure pipeline leakage detection device comprises the following steps:

firstly, a pipe section to be detected of the pressure pipeline is defined from the head end of the pressure pipeline, leakage detection is carried out on the pipe section to be detected, a valve A located at the upstream and a valve B located at the downstream exist at two ends of the length range of the pipe section to be detected, the valve A is closed firstly, after the pipe section to be detected is decompressed, a round hole is formed in one side, close to the valve A, facing the valve B, the head end of an optical fiber sensor penetrates through the round hole and is arranged inside the pipe section to be detected, a sealing piece is adopted to seal a gap between the optical fiber sensor and the round hole, and the tail end of the optical fiber sensor is externally connected with a distributed optical fiber vibration or sound signal demodulator;

step two, opening a valve A, closing a valve B, pressurizing a pipe section to be detected, maintaining pressure when the pressure in the pipe section to be detected reaches the running pressure of a pressure pipeline, opening a distributed optical fiber vibration or sound signal demodulator, detecting the sound data of the whole line of the pipe section to be detected and drawing a whole line sound wave curve;

if the vibration or sound signal of a certain point (point C) of the pipeline is stronger than that of the pipeline along the way, or the vibration or sound signal of the certain point (point C) of the pipeline is stronger than that of the pipeline before, the leakage of the point (point C) can be judged; knocking the ground above the pipeline, continuously adjusting the knocking position, and if the knocking position is superposed with the leakage point (point C), indicating that the leakage point is just below the knocking position.

Among them, it is explained that: in some application scenarios, if the vibration or sound signal of a certain point of the pipeline is found to exceed 5% of the normal data along the pipeline, it can be judged that leakage occurs or third-party construction damage exists. "5%" is merely illustrative and in practical applications, includes but is not limited to "5%".

As the improvement of the technical scheme, when the pipe section to be detected is decompressed, the decompression is stopped until the pressure in the pipe section to be detected is normal pressure, and all media in the pipeline do not need to be emptied.

As an improvement of the technical scheme, when the optical fiber sensor is in the pipe section to be detected, the optical fiber sensor reaches the top of the pipe section to be detected by means of buoyancy of media in the pipe section to be detected.

The invention has the beneficial effects that:

the invention searches for the leakage point and accurately positions by detecting the sound vibration generated by the leakage of the pressure pipeline. Under the condition that the pressure of the pipeline to be checked is relieved but the pipeline does not need to be emptied, the pressure pipeline is provided with a hole, the optical fiber sensor is creatively placed in the pressure pipeline, and the interference of the background noise of the environment when the optical fiber sensor leaks outside the pipeline is reduced to the maximum extent. Then, after the pipe section to be detected is pressurized, the pipeline leakage sound is amplified; in addition, pressurizing the pressurized cavity in the protective sleeve of the optical fiber will also improve the sensitivity of the sensing fiber to leakage sound.

The invention only needs to relieve the pressure of the pressure pipeline to normal pressure, and does not need to evacuate the medium in the pressure pipeline, thereby saving resources, saving energy, protecting environment and saving the time required by evacuation.

The invention has good flexibility, can temporarily detect, can place the optical fiber sensor in the pipeline for a long time to carry out long-term pipeline leakage monitoring, excavation construction damage and pipe burst early warning, and has good construction convenience.

The invention collects real-time digital signals of the safety and the health of the pipeline and can determine the leakage amount by analyzing frequency domain, time domain and intensity signals of the leakage event.

The invention is suitable for leakage detection of pressure pipelines in industries of water diversion, water supply, heat supply and the like, and provides a simple, convenient, economic and efficient device and method for solving the problem of leakage detection of buried pressure pipelines.

Drawings

FIG. 1 is a schematic diagram of the distribution of the fiber optic sensor and the pressure conduit according to the present invention;

FIG. 2 is a schematic structural diagram of the pressure pipeline leakage detection device according to the present invention;

FIG. 3 is a schematic diagram of a pressure line according to the present invention;

FIG. 4 is a schematic structural diagram of an optical fiber sensor according to the present invention;

FIG. 5 is a schematic view of the present invention with a handle attached to the through stud;

fig. 6 is a schematic view of the interior of the seal of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be noted that, unless otherwise specified, "a plurality" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

As shown in fig. 1 to 4, the pressure pipe leakage detection device is used for detecting leakage of a pressure pipe 10, and includes an optical fiber sensor 20, a circular hole 11 for the optical fiber sensor 20 to enter and exit is formed in a side wall of the pressure pipe 10, and a sealing member 30 for sealing a gap between the optical fiber sensor 20 and the circular hole 11 is arranged at the circular hole 11; the optical fiber sensor 20 comprises a sensing optical fiber 21 and an optical fiber protection sleeve 22 which completely wraps the sensing optical fiber 21, the head end of the optical fiber protection sleeve 22 is closed, the tail end of the optical fiber protection sleeve 22 is hermetically connected with the sensing optical fiber 21, and a pressurization cavity 23 with the air pressure larger than the atmospheric pressure is formed in the optical fiber protection sleeve 22.

In an initial stage, an optical fiber protection sleeve 22 is provided for the purpose of protecting the sensing optical fiber 21; the fiber protection sleeve 22 can be prevented from being "crushed" by providing the pressurizing chamber 23. If the pressure inside the optical fiber protection sleeve 22 is normal, the pressure and the impact of the medium inside the sleeve will generate a great amount of abnormal fluctuation, thereby interfering the detection result.

In the present invention, only one circular hole 11 needs to be provided.

The use method of the pressure pipeline leakage detection device comprises the following steps:

firstly, from the head end of a pressure pipeline 10, a to-be-detected pipeline section of the pressure pipeline 10 is defined, leakage detection is carried out on the to-be-detected pipeline section, a valve A located at the upstream and a valve B located at the downstream exist at the two ends of the length range of the to-be-detected pipeline section, the valve A is closed firstly, after the to-be-detected pipeline section is decompressed, a round hole 11 is arranged at one side, close to the valve A, facing towards the valve B, the head end of an optical fiber sensor 20 penetrates through the round hole 11 and is internally arranged in the to-be-detected pipeline section, a gap between the optical fiber sensor 20 and the round hole 11 is sealed by a sealing piece 30, and a distributed optical fiber vibration (sound) signal demodulator is externally connected to the tail end of the optical fiber sensor 20; when light propagates in an optical fiber, if vibration occurs at a certain position, the vibration can modulate the phase of the light in the optical fiber at the position. The distributed optical fiber vibration (sound) signal demodulator realizes the monitoring of vibration events through the change of the phase of light. The position of the vibration point on the length of the optical fiber is determined by multiplying the speed of the light propagating in the optical fiber by the time of the light reaching the vibration position.

And step two, opening the valve A, closing the valve B, pressurizing the pipe section to be detected, maintaining the pressure when the pressure in the pipe section to be detected reaches the running pressure of the pressure pipeline 10, opening the distributed optical fiber vibration (sound) signal demodulator, detecting the sound data of the whole line of the pipe section to be detected and drawing a whole line sound wave curve.

If the vibration or sound signal of a certain point (point C) of the pipeline is stronger than that of the pipeline along the way, or the vibration or sound signal of the certain point (point C) of the pipeline is stronger than that of the pipeline before, the leakage of the point (point C) can be judged; knocking the ground above the pipeline, continuously adjusting the knocking position, and if the knocking position is superposed with the leakage point (point C), indicating that the leakage point is just below the knocking position.

In this embodiment, when the pipe section to be detected is depressurized, the depressurization is stopped until the pressure in the pipe section to be detected is normal pressure.

As the pipeline is only vented to normal pressure, the medium in the pipeline does not need to be vented, the optical fiber sensor can be disposed in the round hole 11, and the resource waste caused by the fact that the medium in the pipeline is completely vented is avoided.

In this embodiment, when the optical fiber sensor 20 is in the pipe section to be detected, the optical fiber sensor 20 is driven to the top of the pipe section to be detected by the buoyancy of the medium in the pipe section to be detected.

Due to the arrangement of the optical fiber protection sleeve 22 and the pressurization cavity 23, the optical fiber sensor 20 is of a hollow structure, so that the optical fiber sensor 20 can float on the liquid level of a medium in the pipe, the static friction force for pushing the optical fiber sensor into the pipe can be greatly reduced, and the optical fiber sensor can be conveniently placed into a manual or long-distance conveyor. In addition, due to the arrangement, the optical fiber sensor 20 can be always tightly attached to the pipe wall of the pressure pipeline 10 due to the existence of buoyancy in the pipe, so that the vibration at the position of the leakage point of the pipeline is ensured to be transmitted to the optical fiber sensor 20 to the maximum extent, and the detection accuracy is effectively improved.

In some embodiments, a large length of pressure tubing 10 may be divided into N sections by valves, with continuous leak detection from upstream to downstream. The pipe section to be detected can be selected between two valves or more than three valves, and the distance can be between hundreds of meters and 40 km; when more than three valves are adopted, all the valves positioned in the middle can be opened.

The advantage of using the optical fiber sensor 20 to detect leakage is that the monitored pressure pipeline 10 is monitored without blind areas in space and time, the optical fiber sensor has the characteristics of large bandwidth and high speed, the system can continuously acquire thousands of sound data from the beginning and draw sound wave curves every minute and every second, and then continuously analyze the sound characteristics along the pipeline from the space and time dimensions. If the sound at a certain position of the pipeline is obviously larger than the sound at the whole line of the pipeline, leakage of the pipeline can occur at the section of the pipeline; if the sound of the place is gradually increased, the place does not move and continuously emits sound, which indicates that the place is not the environmental noise, the place is judged to have leakage, and once the pipeline leaks, the leakage sound continuously exists and the leakage point is continuously enlarged.

The invention finds the leakage point and accurately positions by detecting the sound vibration generated by the leakage of the pressure pipeline. Under the condition that the pressure of the pipeline to be checked is relieved but the pipeline does not need to be emptied, the pressure pipeline is provided with a hole, the optical fiber sensor 20 is creatively placed in the pressure pipeline, and the interference of the environmental background noise when the optical fiber sensor 20 leaks outside the pipeline is reduced to the maximum extent. Then, after the pipe section to be detected is pressurized, the pipeline leakage sound is amplified; in addition, pressurizing the pressurized cavity 23 will also increase the sensitivity of the sensing fiber 21 to leakage sound.

Placing the fiber optic sensor 20 at the wall of the pressure pipe 10 is more sensitive to acoustic signals than placing the fiber optic sensor 20 at the cavity inside the pressure pipe 10 (no pressurization after emptying).

Due to the arrangement of the optical fiber protective sleeve 22 and the pressurizing cavity 23, the optical fiber sensor 20 is caused to be close to the top of the inner wall of the pressure pipe 10 under the buoyancy of the medium in the pipe, which helps to enhance the coupling effect of the leakage signal emitted from the pipe wall and the optical fiber sensor. In some embodiments, if the medium in the pipe is a gas, the fiber-optic sensor 20 can be attached to the bottom of the inner wall of the pressure pipe 10, which helps to enhance the coupling effect between the leakage signal from the pipe wall and the fiber-optic sensor.

The invention only needs to relieve the pressure of the pressure pipeline 10 to normal pressure, and does not need to evacuate the medium in the pressure pipeline 10, thereby saving resources, saving energy, protecting environment and saving the time required by evacuation.

The optical fiber sensor can be pushed into the pressure pipeline 10 manually or by a tractor, so that the construction convenience is good.

Wherein, the air pressure in the pressurizing cavity 23 is preferably 0.4-0.8 Mpa. When the air pressure in the pressurization cavity 23 is too large, the optical fiber protection sleeve 22 is easily burst; when the air pressure in the pressurizing chamber 23 is too small, the sensitizing effect is lost.

The pressure pipeline leakage detection device effectively solves the practical problems of low speed, low efficiency, difficult leakage point positioning and high cost existing in the process of searching for the leakage point of the linear buried pipeline (the pressure pipeline 10) by using the existing point-type sensing products such as a leakage listening instrument, a correlation instrument and the like. The invention is suitable for leakage detection of pressure pipelines in industries of water diversion, water supply, heat supply and the like, and provides a simple, convenient, economic and efficient device and method for solving the problem of leakage detection of buried pressure pipelines.

Example 2

As shown in fig. 5 and 6, the sealing element 30 includes an internal threaded tube 31, an elastic sealing ring 32 located inside the internal threaded tube 31, a through stud 33 in threaded connection with the internal threaded tube 31, and an annular baffle 35 disposed outside the circular hole 11, the baffle 35 is in sealed connection with the side wall of the pressure pipe 10, the end of the internal threaded tube 31 is in sealed connection with the baffle 35, the through stud 33, the elastic sealing ring 32, and the baffle 35 are all sleeved outside the optical fiber sensor 20, and the elastic sealing ring 32 is located between the through stud 33 and the baffle 35.

The seal is completed by tightening the through-going stud 33 against the elastomeric seal ring 32.

Example 3

In some embodiments, a handle 34 is fixedly attached to the end of the through stud 33 for ease of installation.

In some embodiments, the end of the through stud 33 is provided with a convex portion 36, and the through stud 33 and the convex portion 36 form a through bolt.

Example 4

In some embodiments, the protective fiber sleeve 22 is preferably made of a high-temperature resistant, low-temperature resistant, and corrosion resistant material to meet severe detection conditions. The sensing optical fiber 21 is preferably a high and low temperature resistant optical fiber.

In the above embodiment, compared with the background art, the invention is the optical fiber sensor 20 which is as long as the pressure pipeline 10, the sound vibration at the leakage point is directly transmitted to the section of the optical fiber which is closest to the leakage point through the pipeline wall or the medium in the pipeline, and the stability is high. The invention has the maximum detection distance of 40km in one direction and 80km in two directions, and can find a plurality of leakage points at the same time. The buried pipeline construction method only needs to open one hole, and the buried pipeline does not need to be exposed by excavating one section of the hole. The invention can meet the requirement of detecting the pressure pipeline 10 between hundreds of meters and 80km at a time, greatly improves the leakage detection efficiency and reduces the leakage detection cost.

The invention is positioned according to the time of light reaching the leakage point multiplied by the propagation speed of the light in the optical fiber (constant 200000km/s), the precision is very high and is within 2 per thousand; and the positioned leakage point can be confirmed by a method of knocking on the ground above the pipeline, and the knocking part and the leakage point are overlapped, so that the leakage point is just below the knocking part.

In the invention, the alarm accuracy rate of the pressure pipeline leakage detection device and the use method is more than or equal to 97 percent, and the alarm rate is less than or equal to 1 percent.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (9)

1. The utility model provides a pipeline under pressure device that leaks hunting for pipeline under pressure (10) leaks hunting which characterized in that: the device comprises an optical fiber sensor (20), wherein a circular hole (11) for the optical fiber sensor (20) to enter and exit is formed in the side wall of the pressure pipeline (10), and a sealing element (30) for sealing a gap between the optical fiber sensor (20) and the circular hole (11) is arranged at the position of the circular hole (11); the optical fiber sensor (20) comprises a sensing optical fiber (21) and an optical fiber protection sleeve (22) which completely wraps the sensing optical fiber (21), the head end of the optical fiber protection sleeve (22) is closed, the tail end of the optical fiber protection sleeve (22) is in sealing connection with the sensing optical fiber (21), and a pressurizing cavity (23) is formed in the optical fiber protection sleeve (22).

2. A pressure line leak hunting device according to claim 1, wherein: sealing member (30) including internal thread pipe (31), be located the inside elasticity sealing washer (32) of internal thread pipe (31), with internal thread pipe (31) threaded connection's well lead to double-screw bolt (33), set up ring form baffle (35) in round hole (11) outside, baffle (35) and pipeline under pressure (10)'s lateral wall sealing connection, the end and baffle (35) sealing connection of internal thread pipe (31), well lead to double-screw bolt (33), elasticity sealing washer (32), baffle (35) all overlap the outside of establishing at optical fiber sensor (20), elasticity sealing washer (32) are located well lead to between double-screw bolt (33) and baffle (35).

3. A pressure line leak hunting device according to claim 2, wherein: the tail end of the middle through stud (33) is fixedly connected with a handle (34).

4. A pressure pipe leak hunting apparatus according to claim 2, wherein: the tail end of the through stud (33) is provided with a convex part (36), and the through stud (33) and the convex part (36) form a through bolt.

5. A pressure line leak hunting device according to claim 1, wherein: the air pressure in the pressurization cavity (23) is 0.4-0.8 Mpa.

6. A pressure pipe leak hunting apparatus according to claim 1, wherein: gather the sound or the vibration signal that pressure conduit leaked and send through fiber sensor and seek the leak source to through gathering the position that leaks the sound or the vibration event and correspond to the length on the sensing optical fiber and come the preliminary definite pressure conduit leak source, judge the actual position of leak source through strikeing ground above the leak source: if the vibration signal sent out when the floor is knocked is behind the leakage point, the knocking position is moved forwards; if the knocking signal is in front of the leakage point signal, moving the knocking position backwards; and if the knocking signal and the leakage point signal are superposed, judging that the leakage point is just below the knocking part.

7. The use method of the pressure pipeline leakage detection device as claimed in any one of claims 1-6, characterized by comprising the following steps:

firstly, a pipe section to be detected of a pressure pipeline (10) is defined from the head end of the pressure pipeline (10), leakage detection is carried out on the pipe section to be detected, a valve A located at the upstream and a valve B located at the downstream exist at the two ends of the length range of the pipe section to be detected, the valve A is closed firstly, after the pipe section to be detected is decompressed, a round hole (11) is arranged at one side close to the valve A and facing the valve B, the head end of an optical fiber sensor (20) penetrates through the round hole (11) and is embedded into the pipe section to be detected, and a sealing element (30) is adopted to seal a gap between the optical fiber sensor (20) and the round hole (11);

step two, opening the valve A, closing the valve B, pressurizing the pipe section to be detected, maintaining the pressure when the pressure in the pipe section to be detected reaches the running pressure of the pressure pipeline (10), detecting the sound data of the whole line of the pipe section to be detected and drawing a whole line sound wave curve;

if the vibration or sound signal of a certain point of the pipeline is stronger than that of the pipeline along the way or the vibration or sound signal of the certain point of the pipeline is stronger than that of the pipeline before, the leakage of the point can be judged; and knocking the ground above the pipeline, continuously adjusting the knocking position, and if the knocking position is superposed with the leakage point, indicating that the leakage point is just below the knocking position.

8. The use method of the pressure pipeline leakage detection device as claimed in claim 7, wherein the pressure pipeline leakage detection device comprises the following steps: and when the pressure of the pipe section to be detected is released, stopping the pressure release until the pressure in the pipe section to be detected is normal pressure.

9. The use method of the pressure pipeline leakage detection device as claimed in claim 8, wherein: when the optical fiber sensor (20) is arranged in the pipe section to be detected, the optical fiber sensor (20) is driven to the top of the pipe section to be detected by virtue of the buoyancy of the medium in the pipe section to be detected.

Images