Acoustic emission detection system and method for inner leakage of natural gas pipeline valve

Abstract

The invention provides an acoustic emission detection system and method for inner leakage of a natural gas pipeline valve. The system comprises a first acoustic emission sensor mounted on an upstream pipeline, a second acoustic emission sensor mounted on a downstream pipeline, a signal acquisition machine and a signal processor. Wherein the first acoustic emission sensor is used for collecting acoustic signals propagating on an upstream pipeline. The second acoustic emission sensor is used for collecting acoustic signals propagating on the downstream pipeline. And the signal acquisition machine is used for performing amplification processing on the acoustic signal acquired by the first acoustic emission sensor to obtain a first acoustic signal and performing amplification processing on the acoustic signal acquired by the second acoustic emission sensor to obtain a second acoustic signal. The signal processor is used for determining inner leakage data of the valve based on the first sound signal and the second sound signal and determining inner leakage information of the valve based on the inner leakage data so as to achieve automatic detection of inner leakage of the valve, and the detection efficiency can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic emission detection of internal leakage of pipeline valves, and in particular to an acoustic emission detection system and method for internal leakage of natural gas pipeline valves. Background Art

[0002] As the construction of natural gas pipeline networks continues to increase, the use of valves as important control nodes in natural gas pipelines has also increased significantly. Valves play a vital role in the operation and safety of natural gas pipelines. They are used to control and regulate the flow of natural gas, and when the pipeline ruptures or leaks, they isolate the affected pipe section from the normal pipe section to avoid further damage to the normal pipe section and contain gas leakage, ensuring that the pipeline operates within the safety parameters.

[0003] Since gas pipeline valves have the characteristics of high working pressure and large diameter, if internal leakage occurs, it will not only increase the cost of repairing or replacing the valve, but also affect normal transportation operations, equipment maintenance, etc., and even endanger production safety. Therefore, how to detect internal leakage of gas pipeline valves is an urgent problem to be solved.

[0004] At present, manual inspection is often used to detect internal leakage of gas pipeline valves, but the detection efficiency is low. Summary of the invention

[0005] The present invention provides an acoustic emission detection system and method for internal leakage of natural gas pipeline valves, which can realize automatic detection of internal leakage and improve detection efficiency.

[0006] The technical solution of the present invention is as follows:

[0007] On the one hand, the present invention provides an acoustic emission detection system for natural gas pipeline valve internal leakage, which is applied to a natural gas pipeline, wherein the natural gas pipeline includes an upstream pipeline and a downstream pipeline connected by a valve. The system includes: a first acoustic emission sensor installed on the upstream pipeline, a second acoustic emission sensor installed on the downstream pipeline, a signal acquisition machine connected to the first acoustic emission sensor and the second acoustic emission sensor; and a signal processor connected to the signal acquisition machine.

[0008] The first acoustic emission sensor is used to collect the acoustic signal propagating on the upstream pipeline. The second acoustic emission sensor is used to collect the acoustic signal propagating on the downstream pipeline. The signal acquisition machine is used to amplify the acoustic signal collected by the first acoustic emission sensor to obtain the first acoustic signal, and to amplify the acoustic signal collected by the second acoustic emission sensor to obtain the second acoustic signal. The signal processing machine is used to determine the internal leakage data of the valve based on the first acoustic signal and the second acoustic signal, and to determine the internal leakage information of the valve based on the internal leakage data. The internal leakage information is used to characterize whether the valve has internal leakage.

[0009] Based on the above technical solution, the present invention can also be improved as follows.

[0010] Furthermore, the system provided by the present invention also includes a cloud server and a client. The cloud server is connected to the signal processor. The client is connected to the cloud server. The cloud server is used to receive and save the internal leakage data and internal leakage information sent by the signal processor, and send the internal leakage data and internal leakage information to the client. The client is used to prompt the internal leakage data and internal leakage information.

[0011] Furthermore, the signal processor is also used to generate warning information when the internal leakage information indicates that the valve has internal leakage, and send the warning information to the client through the cloud server. The client is also used to receive and prompt the warning information.

[0012] Furthermore, the warning information includes at least one of text, sound and pattern.

[0013] Further, the signal acquisition machine includes a preamplifier signal separator, an STM32 development board, a power supply module and a transformer module. Among them, the power supply module is connected to the preamplifier signal separator, the STM32 development board and the transformer module respectively, and the power supply module is used to power the preamplifier signal separator, the STM32 development board and the transformer module. The transformer module is connected to the power supply module, and is used to adjust the voltage of the power supply module to the preamplifier signal separator, the STM32 development board and the transformer module. The preamplifier signal separator is connected to the STM32 development board, and the preamplifier signal separator is used to amplify the acoustic signal collected by the first acoustic emission sensor and the acoustic signal collected by the second acoustic emission sensor. The STM32 development board is used to determine the first acoustic signal and the second acoustic signal based on the acoustic signal amplified by the preamplifier signal separator.

[0014] Furthermore, the signal processor includes a processor, a computing module, and a communication module connected in sequence. The processor is used to preprocess the first acoustic signal and the second acoustic signal to obtain the preprocessed first acoustic signal and the second acoustic signal. The computing module is used to determine the internal leakage data of the valve based on the preprocessed first acoustic signal and the preprocessed second acoustic signal, and to determine the internal leakage information of the valve based on the internal leakage data. The communication module is used to send the internal leakage data and the internal leakage information to the cloud server.

[0015] Further, the internal leakage data is determined based on the preprocessed first acoustic signal, the preprocessed second acoustic signal and the signal feature value extraction algorithm, and the internal leakage data includes at least one of the signal root mean square value, average value, entropy, energy, maximum value, minimum value and peak value corresponding to the preprocessed first acoustic signal and the second acoustic signal respectively. The internal leakage information includes the first information and the second information, the first information is the parameter information of the valve, and the first information includes the valve number and valve size of the valve. The second information is determined based on the internal leakage data, the internal leakage diagnosis algorithm and the internal leakage rate quantification algorithm, and the second information includes the valve pressure of the valve, the valve internal leakage rate, and the signal root mean square value and root mean square difference corresponding to the preprocessed first acoustic signal and the second acoustic signal respectively.

[0016] Furthermore, the processor is a Jetson Nano processor.

[0017] Furthermore, the first acoustic emission sensor and the second acoustic emission sensor are connected to the signal acquisition machine through a BNC-BNC coaxial cable or a SMA-BNC coaxial cable.

[0018] On the other hand, the present invention provides an acoustic emission detection method for internal leakage of natural gas pipeline valves, which is applied to natural gas pipelines, and the natural gas pipelines include an upstream pipeline and a downstream pipeline connected by a valve. In the method, acoustic signals propagated on the upstream pipeline and the downstream pipeline are collected respectively. The acoustic signal propagated on the upstream pipeline is amplified to obtain a first acoustic signal, and the acoustic signal propagated on the downstream pipeline is amplified to obtain a second acoustic signal. Based on the first acoustic signal and the second acoustic signal, the internal leakage data of the valve is determined, and the internal leakage information of the valve is determined based on the internal leakage data. Among them, the internal leakage information is used to characterize whether the valve has internal leakage. The internal leakage data includes at least one of the signal root mean square value, average value, entropy, energy, maximum value, minimum value and peak value corresponding to the first acoustic signal and the second acoustic signal respectively. The internal leakage information includes the first information and the second information, the first information is the parameter information of the valve, and the first information includes the valve number and valve size of the valve. The second information includes the valve pressure of the valve, the valve internal leakage rate, and the signal root mean square value and root mean square difference corresponding to the first acoustic signal and the second acoustic signal after preprocessing. The internal leakage data and the internal leakage information are saved and prompted. When the internal leakage information indicates that the valve has internal leakage, an early warning message is generated and prompted. The early warning message includes at least one of text, sound and pattern.

[0019] The beneficial effects of the present invention are as follows: the present invention sets a signal acquisition machine connected to the first acoustic emission sensor and the second acoustic emission sensor respectively, and the signal acquisition machine and the signal processor are connected by serial communication using an upper and lower computer, so that real-time online detection of valve internal leakage can be achieved, with less reliance on manual labor. Moreover, relying on the powerful computing power of the Jetson Nano processor, the computing efficiency can be improved and the acquisition time can be shortened. The signal processor of the present invention can upload diagnostic information data to a cloud server, which can facilitate users to view historical data of internal leakage diagnosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of an acoustic emission detection system for internal leakage of a natural gas pipeline valve provided by the present invention;

[0021] Figure 2 A schematic diagram of the structure of a signal acquisition machine provided by the present invention;

[0022] Figure 3 A schematic diagram of the structure of a signal processor provided by the present invention;

[0023] Figure 4 A schematic diagram of a flow chart of an acoustic emission detection method for internal leakage of a natural gas pipeline valve provided by the present invention;

[0024] Figure 5 A schematic flow chart of another acoustic emission detection method for internal leakage of natural gas pipeline valves provided by the present invention.

[0025] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0026] 1. Valve, 2. Upstream pipeline, 3. Downstream pipeline, 4. First acoustic emission sensor, 5. Second acoustic emission sensor, 6. Signal acquisition machine, 7. Signal processor, 8. Cloud server, 9. Client, 61. Preamplifier signal separator, 62. STM32 development board, 63. Power supply module, 64. Transformer module, 71. Processor, 72. Computing module, 73. Communication module. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Among them, in the description of the present application, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship, for example, A / B can represent A or B; "and / or" in the present application is only a description of the association relationship of the associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. And, in the description of the present application, unless otherwise specified, "multiple" refers to two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple. In addition, in order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second" and the like are used to distinguish between the same items or similar items with substantially the same functions and effects. Those skilled in the art will understand that the words "first", "second" and the like do not limit the quantity and execution order, and the words "first", "second" and the like do not necessarily limit the differences. At the same time, in the embodiments of the present application, the words "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or design.

[0028] The present invention provides an acoustic emission detection system for natural gas pipeline valve internal leakage, which is applied to natural gas pipelines. Figure 1 , the natural gas pipeline includes an upstream pipeline 2 and a downstream pipeline 3 connected by a valve 1. Figure 1 The system provided by the present invention includes: a first acoustic emission sensor 4 installed on an upstream pipeline 2, a second acoustic emission sensor 5 installed on a downstream pipeline 3, a signal acquisition machine 6 connected to the first acoustic emission sensor 4 and the second acoustic emission sensor 5; and a signal processor 7 connected to the signal acquisition machine 6.

[0029] The first acoustic emission sensor 4 is used to collect the acoustic signal propagating on the upstream pipeline 2. The second acoustic emission sensor 5 is used to collect the acoustic signal propagating on the downstream pipeline 3. The signal acquisition machine 6 is used to amplify the acoustic signal collected by the first acoustic emission sensor 4 to obtain a first acoustic signal, and to amplify the acoustic signal collected by the second acoustic emission sensor 5 to obtain a second acoustic signal. The signal processor 7 is used to determine the internal leakage data of the valve 1 based on the first acoustic signal and the second acoustic signal, and to determine the internal leakage information of the valve 1 based on the internal leakage data. The internal leakage information is used to characterize whether the valve 1 has internal leakage.

[0030] In some embodiments, the first acoustic emission sensor 4 is an acoustic emission sensor, which is cylindrical, and the shell is made of aluminum alloy, and is used to obtain the non-leakage signal SW15, and amplify the signal through the signal acquisition machine 6 to obtain the signal SW17 (which may also be referred to as the first acoustic signal in the embodiment of the present application). The second acoustic emission sensor 5 is also an acoustic emission sensor, which is cylindrical, and the shell is made of aluminum alloy, and is used to obtain the original leakage signal SW16, and amplify the signal through the signal acquisition machine 6 to obtain the signal SW18 (which may also be referred to as the second acoustic signal in the embodiment of the present application).

[0031] In some embodiments, coupling agent may be applied to the sensing ends of the first acoustic emission sensor and the second acoustic emission sensor to improve detection accuracy.

[0032] It should be noted that the non-leakage signal SW15 is a noise signal propagating on the wall of the upstream pipe 2, which is captured by the first acoustic emission sensor 4 and amplified to SW17; the original leakage acoustic emission signal SW16 is generated by the medium GO behind the leak hole in the valve 1 under the action of the pressure difference and propagates on the wall of the downstream pipe 3, and is captured by the second acoustic emission sensor 5 and amplified to SW18. The medium GO includes but is not limited to: natural gas, carbon monoxide, carbon dioxide, hydrogen, oxygen, nitrogen and other gases.

[0033] In some embodiments, see Figure 1 The system provided by the present invention further includes a cloud server 8 and a client 9. The cloud server 8 is connected to the signal processor 7. The client 9 is connected to the cloud server 8. The cloud server 8 is used to receive and save the internal leakage data and internal leakage information sent by the signal processor 7, and send the internal leakage data and internal leakage information to the client 9. The client 9 is used to prompt the internal leakage data and internal leakage information.

[0034] In some embodiments, the signal processor 7 is further used to generate warning information when the internal leakage information indicates that the valve 1 has internal leakage, and send the warning information to the client 9 through the cloud server 8. The client 9 is also used to receive and prompt the warning information.

[0035] In some embodiments, the warning information includes at least one of text, sound, and pattern.

[0036] In some embodiments, see Figure 2 The signal acquisition machine 6 includes a preamplifier signal separator 61, an STM32 development board 62, a power supply module 63 and a transformer module 64.

[0037] Wherein, the power supply module 63 is connected with the front-end signal separator 61, the STM32 development board 62 and the transformer module 64 respectively, and the power supply module 63 is used to power the front-end signal separator 61, the STM32 development board 62 and the transformer module 64. The transformer module 64 is connected with the power supply module 63, and is used to adjust the voltage of the power supply module 63 to the front-end signal separator 61, the STM32 development board 62 and the transformer module 64 (for example, the power supply voltage is adjusted to ± 15V, 3.3V, 5V, 28V, etc.). The front-end signal separator 61 is connected with the STM32 development board 62, and the front-end signal separator 61 is used to amplify the acoustic signal collected by the first acoustic emission sensor 4 and the acoustic signal collected by the second acoustic emission sensor 5. The STM32 development board 62 is used to determine the first acoustic signal and the second acoustic signal based on the acoustic signal after amplification by the front-end signal separator 61.

[0038] In some embodiments, see Figure 3 The signal processor 7 includes a processor 71, a computing module 72 and a communication module 73 connected in sequence. The processor 71 is used to preprocess the first acoustic signal and the second acoustic signal to obtain the preprocessed first acoustic signal and the second acoustic signal. The computing module 72 is used to determine the internal leakage data of the valve 1 based on the preprocessed first acoustic signal and the preprocessed second acoustic signal, and to determine the internal leakage information of the valve 1 based on the internal leakage data. The communication module 73 is used to send the internal leakage data and the internal leakage information to the cloud server 8 (in the embodiment of the present application, the internal leakage data and the internal leakage information may also be referred to as internal leakage diagnostic data information or SW19).

[0039] Exemplarily, the STM32 development board 62 transmits the non-leakage signal SW17 and the leakage signal SW18 to the Jetson Nano processor via serial communication, and relies on the powerful data processing capability of the processor to perform data preprocessing (e.g., cleaning, denoising, etc.), and sends the processed non-leakage signal SW17 and the leakage signal SW18 to the calculation module 72, so as to determine the internal leakage data and the internal leakage information based on the calculation module 72 by the built-in preset algorithm. Afterwards, the calculation module 72 can send the determined internal leakage data and the internal leakage information to the communication module. Wherein, in order to improve the communication rate, the communication module can be a wireless communication module with 4G or 5G functions.

[0040] The communication module outputs the processed user-readable internal leakage data and internal leakage information, and transmits the internal leakage data and internal leakage information to the cloud server 8. The cloud server can receive the internal leakage data and internal leakage information, and save the received internal leakage data and internal leakage information as historical data so that the user can retrieve and view it at any time. The cloud server can also send the received internal leakage data and internal leakage information to the client in real time for the user to monitor in real time.

[0041] In some embodiments, the internal leakage data is determined based on the preprocessed first acoustic signal, the preprocessed second acoustic signal and the signal feature value extraction algorithm, and the internal leakage data includes at least one of the signal root mean square value, average value, entropy, energy, maximum value, minimum value and peak value corresponding to the preprocessed first acoustic signal and the second acoustic signal respectively. The internal leakage information includes first information and second information, the first information is the parameter information of valve 1, and the first information includes valve 1 number and valve 1 size of valve 1. The second information is determined based on the internal leakage data, the internal leakage diagnosis algorithm and the internal leakage rate quantification algorithm, and the second information includes valve 1 pressure of valve 1, valve 1 internal leakage rate, and the signal root mean square value and root mean square difference corresponding to the preprocessed first acoustic signal and the second acoustic signal respectively.

[0042] In some embodiments, processor 71 is a Jetson Nano processor 71 .

[0043] In some embodiments, the first acoustic emission sensor 4 and the second acoustic emission sensor 5 are connected to the signal acquisition machine 6 via a BNC-BNC coaxial cable or a SMA-BNC coaxial cable.

[0044] The present invention also provides an acoustic emission detection method for natural gas pipeline valve internal leakage, which is applied to a natural gas pipeline, wherein the natural gas pipeline includes an upstream pipeline and a downstream pipeline connected by a valve. Figure 4 The method comprises the following steps S401-S403:

[0045] S401: Acoustic signals propagating on the upstream pipeline and the downstream pipeline are collected respectively.

[0046] S402: Amplify the acoustic signal propagating on the upstream pipeline to obtain a first acoustic signal, and amplify the acoustic signal propagating on the downstream pipeline to obtain a second acoustic signal.

[0047] S403: Determine internal leakage data of the valve based on the first acoustic signal and the second acoustic signal, and determine internal leakage information of the valve based on the internal leakage data.

[0048] Among them, the internal leakage information is used to characterize whether the valve has internal leakage. The internal leakage data includes at least one of the signal root mean square value, average value, entropy, energy, maximum value, minimum value and peak value corresponding to the first sound signal and the second sound signal respectively. The internal leakage information includes the first information and the second information, the first information is the parameter information of the valve, and the first information includes the valve number and valve size of the valve. The second information includes the valve pressure of the valve, the valve internal leakage rate, and the signal root mean square value and root mean square difference corresponding to the first sound signal and the second sound signal after preprocessing. Save and prompt the internal leakage data and internal leakage information. When the internal leakage information indicates that the valve 1 has internal leakage, generate and prompt early warning information. The early warning information includes at least one of text, sound and pattern.

[0049] The present invention also provides an acoustic emission detection method for natural gas pipeline valve internal leakage, which is applied to a natural gas pipeline, wherein the natural gas pipeline includes an upstream pipeline and a downstream pipeline connected by a valve. Figure 5 , the method comprises the following steps L1-L5:

[0050] L1: Fix the first acoustic emission sensor on the upstream pipe far away from the valve through a magnetic clamp, and fix the second acoustic emission sensor on the downstream pipe close to the valve through a magnetic clamp.

[0051] L2: Connect the first acoustic emission sensor and the second acoustic emission sensor to the signal acquisition machine through a BNC-BNC coaxial cable or a SMA-BNC coaxial cable.

[0052] L3: The signal acquisition machine collects the non-leakage signal SW17 and the leakage signal SW18, and transmits the signal to the signal processing machine through serial communication;

[0053] L4: The signal processor processes the signal into internal leakage diagnosis data information SW19, and uploads the internal leakage diagnosis data information SW19 to the cloud server.

[0054] The internal leakage diagnosis data information SW19 includes the internal leakage data and internal leakage information described in the above embodiment.

[0055] L5: The cloud server pushes the internal leakage diagnosis data information SW19 to the client.

[0056] L6: The signal processor determines whether internal leakage occurs based on the internal leakage diagnosis data information SW19. When internal leakage occurs, it generates warning information and uploads it to the cloud server. The cloud server then pushes the alarm information and internal leakage diagnosis data SW19 to the WeChat client.

[0057] In some embodiments, before step L1, the method may also include: burning a machine learning model trained by the user himself (there is a preset model in the system, and this step can be omitted if there is no need).

[0058] In the above method, SW19 can be pushed to the user's mobile phone or computer terminal and other clients for display through the cloud server, which solves the problem that the inspection personnel must be present for the internal leakage detection in the past. By using the Jetson Nano processor in the signal processor, the acquisition efficiency can be effectively improved and the acquisition time can be reduced. The problem that the previous acoustic emission detection device collected data slowly and inaccurately is solved. The calculation module in the signal processor can be burned by the user's own program, which solves the problem of poor versatility of the previous acoustic emission internal leakage detector. The historical internal leakage data is saved by the cloud server and displayed on the client interface, which solves the problem that it is inconvenient for the internal leakage detection system to save historical data.

[0059] In some schemes, multiple embodiments of the present application can be combined, and the combined scheme can be implemented. Optionally, some operations in the process of each method embodiment are optionally combined, and / or the order of some operations is optionally changed. In addition, the execution order between the steps of each process is only exemplary and does not constitute a restriction on the execution order between the steps. There can also be other execution orders between the steps. It is not intended to indicate that the execution order is the only order in which these operations can be performed. A person of ordinary skill in the art will think of a variety of ways to reorder the operations described herein. In addition, it should be noted that the process details involved in a certain embodiment of this article are also applicable to other embodiments in a similar manner, or different embodiments can be used in combination.

[0060] In addition, some steps in the method embodiment may be equivalently replaced by other possible steps. Alternatively, some steps in the method embodiment may be optional and may be deleted in certain usage scenarios. Alternatively, other possible steps may be added to the method embodiment. Furthermore, the method embodiments may be implemented separately or in combination.

[0061] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the system can be divided into different functional modules to complete all or part of the functions described above.

[0062] In the several embodiments provided in the present application, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of systems or units, which can be electrical, mechanical or other forms.

[0063] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0064] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium, including several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor (processor) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program code.

[0065] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application shall be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An acoustic emission detection system for internal leakage of natural gas pipeline valves, characterized in that: The invention is applied to a natural gas pipeline, wherein the natural gas pipeline comprises an upstream pipeline (2) and a downstream pipeline (3) connected by a valve (1); the system comprises: A first acoustic emission sensor (4) installed on the upstream pipeline (2), a second acoustic emission sensor (5) installed on the downstream pipeline (3), a signal acquisition machine (6) connected to the first acoustic emission sensor (4) and the second acoustic emission sensor (5); and a signal processing machine (7) connected to the signal acquisition machine (6); The first acoustic emission sensor (4) is used to collect the acoustic signal propagating on the upstream pipeline (2); the second acoustic emission sensor (5) is used to collect the acoustic signal propagating on the downstream pipeline (3); the signal acquisition machine (6) is used to amplify the acoustic signal collected by the first acoustic emission sensor (4) to obtain a first acoustic signal, and to amplify the acoustic signal collected by the second acoustic emission sensor (5) to obtain a second acoustic signal; the signal processing machine (7) is used to determine the internal leakage data of the valve (1) based on the first acoustic signal and the second acoustic signal, and to determine the internal leakage information of the valve (1) based on the internal leakage data; the internal leakage information is used to indicate whether the valve (1) has internal leakage.

2. The system according to claim 1, characterized in that It also includes: a cloud server (8) and a client (9); the cloud server (8) is connected to the signal processor (7); the client (9) is connected to the cloud server (8); The cloud server (8) is used to receive and store the internal leakage data and the internal leakage information sent by the signal processor (7), and send the internal leakage data and the internal leakage information to the client (9); the client (9) is used to prompt the internal leakage data and the internal leakage information.

3. The system according to claim 2, characterized in that The signal processor (7) is also used to generate warning information when the internal leakage information indicates that the valve (1) has internal leakage, and send the warning information to the client (9) through the cloud server (8); the client (9) is also used to receive and prompt the warning information.

4. The system according to claim 3, characterized in that The warning information includes at least one of text, sound and pattern.

5. The system according to claim 4, characterized in that The signal acquisition machine (6) comprises: a preamplifier signal separator (61), an STM32 development board (62), a power supply module (63) and a voltage conversion module (64); The power supply module (63) is respectively connected to the preamplifier signal separator (61), the STM32 development board (62) and the transformer module (64), and the power supply module (63) is used to supply power to the preamplifier signal separator (61), the STM32 development board (62) and the transformer module (64); The voltage conversion module (64) is connected to the power supply module (63) and is used to adjust the voltage of the power supply module (63) supplying power to the preamplifier signal separator (61), the STM32 development board (62) and the voltage conversion module (64); The preamplifier signal separator (61) is connected to the STM32 development board (62), and the preamplifier signal separator (61) is used to amplify the acoustic signal collected by the first acoustic emission sensor (4) and the acoustic signal collected by the second acoustic emission sensor (5); the STM32 development board (62) is used to determine the first acoustic signal and the second acoustic signal based on the acoustic signal amplified by the preamplifier signal separator (61).

6. The system according to claim 5, characterized in that The signal processing machine (7) comprises a processor (71), a computing module (72) and a communication module (73) connected in sequence; The processor (71) is used to preprocess the first acoustic signal and the second acoustic signal to obtain the preprocessed first acoustic signal and the second acoustic signal; the calculation module (72) is used to determine the internal leakage data of the valve (1) based on the preprocessed first acoustic signal and the preprocessed second acoustic signal, and to determine the internal leakage information of the valve (1) based on the internal leakage data; and the communication module (73) is used to send the internal leakage data and the internal leakage information to the cloud server (8).

7. The system according to claim 6, characterized in that The internal leakage data is determined based on the first acoustic signal after preprocessing, the second acoustic signal after preprocessing and a signal feature value extraction algorithm, and the internal leakage data includes at least one of the signal root mean square value, average value, entropy, energy, maximum value, minimum value and peak value corresponding to the first acoustic signal and the second acoustic signal after preprocessing respectively; The internal leakage information includes first information and second information, wherein the first information is parameter information of the valve (1), and the first information includes the valve number and valve size of the valve (1); the second information is determined based on the internal leakage data, the internal leakage diagnosis algorithm and the internal leakage rate quantification algorithm, and the second information includes the valve pressure of the valve (1), the valve internal leakage rate, and the signal root mean square value and root mean square difference value corresponding to the first sound signal and the second sound signal after preprocessing.

8. The system according to claim 7, characterized in that The processor (71) is a Jetson Nano processor.

9. The system according to claim 8, characterized in that The first acoustic emission sensor (4) and the second acoustic emission sensor (5) are connected to the signal acquisition machine (6) via a BNC-BNC coaxial cable or a SMA-BNC coaxial cable.

10. An acoustic emission detection method for internal leakage of natural gas pipeline valves, characterized in that: Applied to a natural gas pipeline, the natural gas pipeline includes an upstream pipeline and a downstream pipeline connected by a valve; the method includes: respectively collecting acoustic signals propagating on the upstream pipeline and the downstream pipeline; Amplifying the acoustic signal propagating on the upstream pipeline to obtain a first acoustic signal, and amplifying the acoustic signal propagating on the downstream pipeline to obtain a second acoustic signal; Based on the first acoustic signal and the second acoustic signal, the internal leakage data of the valve is determined, and based on the internal leakage data, the internal leakage information of the valve is determined; the internal leakage information is used to characterize whether the valve has internal leakage; the internal leakage data includes at least one of the signal root mean square value, average value, entropy, energy, maximum value, minimum value and peak value corresponding to the first acoustic signal and the second acoustic signal respectively; the internal leakage information includes first information and second information, the first information is the parameter information of the valve, the first information includes the valve number and valve size of the valve; the second information includes the valve pressure of the valve, the valve internal leakage rate, and the signal root mean square value and root mean square difference corresponding to the first acoustic signal and the second acoustic signal respectively after preprocessing; Saving and prompting the endoleak data and the endoleak information; When the internal leakage information indicates that the valve has internal leakage, an early warning message is generated and prompted; the early warning message includes at least one of text, sound and pattern.

Images