Pipeline pressure leakage detection method

Abstract

The invention relates to the technical field of pipeline detection, and discloses a pipeline pressure leakage detection method which comprises the following steps: S1, closing a mounting base body around a to-be-detected pipeline, and completing mechanical fixation through a quick locking structure; s2, a self-adaptive adjusting mechanism automatically adjusts a detection gap according to the temperature of the pipeline; s3, the differential pressure sensor array continuously collects circumferential pressure gradient data of the pipeline; s4, the signal processing unit executes temperature compensation and noise filtering processing; s5, the mode recognition module judges a leakage event based on the convolutional neural network and calculates a positioning coordinate; s6, the alarm unit triggers sound-light alarm and sends a wireless alarm signal; the pressure gradient change is captured through the layout of the annular array differential pressure sensor, and precise leakage detection and positioning are realized in combination with the self-adaptive adjusting mechanism; the data of the differential pressure sensor is processed and recorded through the signal processing unit; the pipeline can be remotely monitored through the wireless transmission module, and the system is suitable for pipeline system monitoring under complex working conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline detection, and more particularly to a pipeline leak pressure detection method. Background Art

[0002] Petroleum, one of the main objects of geological exploration, is a viscous, dark brown liquid, known as the "blood of industry". There is petroleum storage in some areas of the upper crust. Its main components are mixtures of various alkanes, cycloalkanes, and aromatic hydrocarbons. Currently, petroleum is transported through pipelines, so the leak detection of pipelines is very important.

[0003] Currently, when detecting pipeline leaks, first manually read the digital pressure gauge to record the initial pressure value in the pipeline, then use an inflation hose to fill the pipeline with compressed air. After inflation, manually read the digital pressure gauge again to record the final pressure value in the air pipeline. By judging whether the difference between the initial pressure value and the final pressure value is within the specified range, it is determined whether there is a leakage in the pipeline.

[0004] This detection method has the following problems: manually recording data is time-consuming and laborious, the data has human errors, and it is not convenient for management. Summary of the Invention

[0005] The purpose of the present invention is to provide a pipeline leak pressure detection method, aiming to solve the problem that in the prior art, it is time-consuming and laborious to detect pipeline leaks by manually recording data.

[0006] The present invention is implemented as follows. The pipeline leak pressure detection method includes the following steps:

[0007] S1. Surround the pipeline to be measured with the installation base and complete mechanical fixation through a quick-locking structure; a pressure detection unit, a signal processing unit, an alarm unit, and a wireless transmission module are provided in the installation base;

[0008] S2. An adaptive adjustment mechanism is provided on the inner side of the installation base, and the adaptive adjustment mechanism automatically adjusts the detection gap according to the pipeline temperature;

[0009] S3. The pressure detection unit includes at least three differential pressure sensors distributed circumferentially along the pipe body; the differential pressure sensor array continuously collects pipeline circumferential pressure gradient data;

[0010] S4. The signal processing unit includes a signal amplification circuit, an FIR digital filter, and a pattern recognition module; the signal processing unit performs temperature compensation and noise filtering processing;

[0011] S5. The pattern recognition module determines leakage events and calculates positioning coordinates based on a convolutional neural network;

[0012] S6. The alarm unit triggers an audible and visual alarm and sends a wireless alarm signal.

[0013] Further, in step S1, the pressure detection unit further includes a temperature compensation module, and the temperature compensation module includes NTC thermistors symmetrically arranged on both sides of the differential pressure sensor.

[0014] Further, in step S3, the differential pressure sensor adopts a MEMS piezoresistive sensor, which forms an annular array layout at 120° intervals, and a detection gap of 0.5 - 2 mm is formed between the detection surface of each sensor and the pipe wall; a nano-hydrophobic coating is provided on the detection surface of the differential pressure sensor.

[0015] Further, in step S2, the adaptive adjustment mechanism includes a shape memory alloy spring, a sliding guide rail, and a sensor bracket for installing the differential pressure sensor. The sliding guide rail is arranged parallel to the inner wall of the installation base along the circumferential direction. The sensor bracket is slidably matched with the sliding guide rail. One end of the shape memory alloy spring is inserted into the inner side wall of the installation base, and the other end of the shape memory alloy spring presses against the sensor bracket; the sensor bracket is connected to the shape memory alloy spring through a hinge ball head.

[0016] Further, in step S1, a contact gasket is provided on the installation base. The contact gasket is in a semi-circular structure and is fixed to the open end of the installation base through a pre-tightening bolt. A silicone rubber sealing layer is provided on the inner surface of the contact gasket.

[0017] Further, the installation base adopts a segmented snap structure. The installation base includes an upper half ring and a lower half ring arranged symmetrically; the quick locking structure includes a spring steel sheet and a magnetic attraction fastener. The spring steel sheet is in a double-bent sheet structure. The root of the spring steel sheet is fixed to the inner side of the upper half ring, and a wedge-shaped locking tongue is provided at the free end of the spring steel sheet;

[0018] The magnetic attraction fastener is composed of a permanent magnet and a magnetic conductive plate. The permanent magnet is embedded in the groove of the lower half ring, and the magnetic conductive plate is installed on the top of the permanent magnet. A positioning groove is formed by inwards depression in the magnetic conductive plate, and the wedge-shaped locking tongue is inserted into the positioning groove and magnetically attracted and matched with the magnetic conductive plate.

[0019] Further, a silicone rubber buffer layer is provided on the contact surface between the magnetic conductive plate and the wedge-shaped locking tongue.

[0020] Further, a visualization display unit is further included. The visualization display unit includes a flexible electronic paper display screen and a three-color LED warning light, and the electronic paper display screen can display the pressure distribution cloud map in real time.

[0021] Further, in step S6, the three-color LED warning light switches the display mode according to the severity of the leakage: when the probability is >90%, it flashes red (2 Hz); when the probability is 70-90%, it lights yellow constantly.

[0022] The electronic paper display screen generates a pressure gradient cloud map and marks the leakage hot spot area.

[0023] Further, it also includes a redundancy detection unit. The redundancy detection unit includes an ultrasonic sensor and an infrared thermal imager, and the detection data of both are fused and processed with the pressure detection unit.

[0024] Redundancy verification step S5: When the pressure detection unit determines leakage, start the ultrasonic sensor to detect the acoustic emission signal in the frequency band of 20-50 kHz; the infrared thermal imager scans the surface temperature distribution of the pipeline; when the three-source data is consistent, confirm the leakage event.

[0025] Compared with the prior art, the pipeline leakage pressure detection method provided by the present invention can install the installation base on the pipeline through a quick-locking structure, capture the pressure gradient change through the annular array differential pressure sensor layout, and combine with the adaptive adjustment mechanism to achieve accurate leakage detection and positioning; the signal processing unit processes and records the data of the differential pressure sensor, and when the data is abnormal, an alarm can be issued through the alarm unit; the pipeline can be remotely monitored through the wireless transmission module, which is applicable to the monitoring of pipeline systems under complex working conditions; it solves the problem that it is time-consuming and laborious to manually record data for pipeline leakage detection. Brief Description of the Drawings

[0026] Figure 1 is a schematic flow chart of the pipeline leakage pressure detection method provided by the present invention;

[0027] Figure 2 is a schematic structural diagram of the installation base provided by the present invention;

[0028] Figure 3 is a sectional structural diagram of the installation base provided by the present invention;

[0029] Figure 4 is an open structural diagram of the installation base provided by the present invention;

[0030] Figure 5 is the present invention Figure 2 an enlarged structural diagram of A therein;

[0031] Figure 6 is the present invention Figure 2 an enlarged structural diagram of B therein.

[0032] In the figure: mounting base 10, adaptive adjustment mechanism 20, quick locking structure 30, differential pressure sensor 40, electronic paper display screen 50, upper half ring 11, lower half ring 12, contact gasket 13, silicone rubber sealing layer 14, shape memory alloy spring 21, sliding guide 22, sensor bracket 23, hinge ball head 24, spring steel sheet 31, magnetic attraction fastener 32, wedge-shaped locking tongue 33, permanent magnet 321, magnetic conductive plate 322, silicone rubber buffer layer 323. Detailed implementation mode

[0033] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0035] In the drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation of the present invention. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0036] Refer to Figures 1-6 As shown, it is a preferred embodiment provided by the present invention.

[0037] The pipeline leakage pressure detection method includes the following steps:

[0038] S1. Surround the pipeline to be measured with the mounting base 10 and complete mechanical fixation through the quick locking structure 30; a pressure detection unit, a signal processing unit, an alarm unit and a wireless transmission module are arranged in the mounting base 10;

[0039] S2. An adaptive adjustment mechanism 20 is arranged on the inner side of the mounting base 10, and the adaptive adjustment mechanism 20 automatically adjusts the detection gap to 1.2 ± 0.2 mm according to the pipeline temperature;

[0040] S3. The pressure detection unit includes at least three differential pressure sensors 40 distributed circumferentially along the pipe body; the differential pressure sensor array continuously collects pipeline circumferential pressure gradient data;

[0041] S4. The signal processing unit includes a signal amplification circuit, an FIR digital filter, and a pattern recognition module; the signal processing unit performs temperature compensation and noise filtering processing;

[0042] S5. The pattern recognition module determines the leakage event based on a convolutional neural network and calculates the positioning coordinates;

[0043] S6. The alarm unit triggers an audible and visual alarm and sends a wireless alarm signal.

[0044] For the pipeline leakage pressure detection method provided above, the installation base 10 can be installed on the pipeline through the quick locking structure 30, and the pressure gradient change is captured through the layout of the annular array differential pressure sensor 40. Combined with the adaptive adjustment mechanism 20, accurate leakage detection and positioning are achieved; the data of the differential pressure sensor 40 is processed and recorded by the signal processing unit. When the data is abnormal, an alarm can be issued through the alarm unit; the pipeline can be remotely monitored through the wireless transmission module, which is applicable to the monitoring of pipeline systems under complex working conditions; it solves the problem that it is time-consuming and laborious to manually record data for pipeline leakage detection.

[0045] The signal processing unit includes: a signal amplification circuit, an FIR digital filter, and a pattern recognition module, where the pattern recognition module stores 12 typical leakage waveform features.

[0046] FIR digital filter: Design a 128th-order band-pass filter (cutoff frequency 0.1 - 200 Hz);

[0047] Neural network model: TensorFlow Lite architecture, the input layer is 3×256 pressure time series data, and the output layer includes leakage probability and positioning quadrant.

[0048] The wireless transmission module can upload the data of the pressure detection unit to a mobile phone or a terminal network for easy viewing and saving.

[0049] In this embodiment, in step S1, the pressure detection unit further includes a temperature compensation module. The temperature compensation module includes NTC thermistors symmetrically arranged on both sides of the differential pressure sensor 40. The signal processing unit has a built-in temperature-pressure coupling compensation algorithm. The temperature compensation module plays a key role in pipeline leakage pressure detection and is mainly used to eliminate the influence of temperature changes on the measurement accuracy of the sensor.

[0050] The annular array differential pressure sensor 40 cooperating with the temperature compensation module: breaks through the limitation of traditional single-point detection, captures the pressure gradient change through the circumferentially distributed sensor array, and combines temperature compensation to eliminate environmental interference, which can improve the positioning accuracy.

[0051] In this embodiment, in step S3, the differential pressure sensor 40 adopts a MEMS piezoresistive sensor, which is arranged in an annular array layout at intervals of 120°, and a detection gap of 0.5-2 mm is formed between the detection surface of each sensor and the pipe wall;

[0052] The MEMS sensor is an important branch of MEMS devices. As an important part of the microelectromechanical system, the MEMS sensor is a functional device that realizes the sensing and signal processing of the microelectromechanical system.

[0053] The differential pressure sensor 40 selects a Bosch BMP581 type MEMS sensor (range 0-10 MPa, accuracy ±0.05% FS);

[0054] The detection surface of the differential pressure sensor 40 is provided with a nano-hydrophobic coating. The coating thickness is 50-80 μm, and the contact angle is ≥150°. The nano-hydrophobic coating is formed by molecular-level surface modification + nano-structure construction, which prevents liquid penetration interference. While ensuring the differential pressure sensing accuracy, it significantly enhances the robustness of the device in a complex fluid environment.

[0055] In this embodiment, in step S2, the adaptive adjustment mechanism 20 includes a shape memory alloy spring 21, a sliding guide rail 22, and a sensor bracket 23 for installing the differential pressure sensor 40. The sliding guide rail 22 is arranged parallel to the inner wall of the installation base 10 in the circumferential direction. The sensor bracket 23 is slidably matched with the sliding guide rail 22. One end of the shape memory alloy spring 21 is inserted into the inner side wall of the installation base 10, and the other end of the shape memory alloy spring 21 presses against the sensor bracket 23; the sensor bracket 23 is connected to the shape memory alloy spring 21 through a hinge ball head 24. The rotation angle range of the hinge ball head 24 is ±15°. The deformation of the shape memory alloy spring 21 has a linear relationship with the temperature, and the detection gap is automatically adjusted when the temperature changes.

[0056] The sensor bracket 23 is made of a flexible material. In this way, the sensor bracket 23 moves radially inward along the sliding guide rail 22 to compensate for the pipe expansion. The shape memory alloy spring 21 is used to push the sensor bracket 23 to improve the positioning detection of the sensor bracket 23 driving the differential pressure sensor 40.

[0057] In this embodiment, in step S1, a contact gasket 13 is provided on the installation base 10. The contact gasket 13 is in a semi-circular structure and is fixed to the open end of the installation base 10 through a pre-tightening bolt. A silicone rubber sealing layer 14 is provided on the inner surface of the contact gasket 13.

[0058] Through the cooperation of the contact gasket 13 and the silicone rubber sealing layer 14, the open end of the installation base 10 is clamped and sealed around the pipeline, thereby reducing the influence of the external environment on the differential pressure sensor 40 and reducing the vibration interference of the installation base 10.

[0059] In this embodiment, the installation base 10 adopts a segmented snap structure. The installation base 10 includes an upper half-ring 11 and a lower half-ring 12 which are symmetrically arranged; the quick-locking structure 30 includes a spring steel sheet 31 and a magnetic snap 32, and can complete the closing of the pipe body within 3 seconds; the spring steel sheet 31 is a double-bent sheet structure, the root of the spring steel sheet 31 is fixed to the inner side of the upper half-ring 11, and a wedge-shaped locking tongue 33 is arranged at the free end of the spring steel sheet 31;

[0060] The magnetic snap 32 is composed of a permanent magnet 321 (NdFeB-42H) and a magnetic conductive plate 322 (430 stainless steel). The permanent magnet 321 is embedded in the groove of the lower half-ring 12, the magnetic conductive plate 322 is installed on the top of the permanent magnet 321, and the magnetic conductive plate 322 is magnetically coupled with the wedge-shaped locking tongue 33; a positioning groove is formed by inward depression in the magnetic conductive plate 322, and the wedge-shaped locking tongue 33 is inserted into the positioning groove to be magnetically coupled with the magnetic conductive plate 322.

[0061] The quick-locking structure 30 can be quickly inserted into the magnetic snap 32 through the cooperation of the spring steel sheet 31 and the wedge-shaped locking tongue 33. The magnetic snap 32 uses the permanent magnet 321 and the magnetic conductive plate 322 to magnetically hold the wedge-shaped locking tongue 33, so as to quickly close between the upper half-ring 11 and the lower half-ring 12; the magnetic conductive plate 322 positions the wedge-shaped locking tongue 33 through the positioning groove.

[0062] In this embodiment, a silicone rubber buffer layer 323 is arranged on the contact surface between the magnetic conductive plate 322 and the wedge-shaped locking tongue 33. In this way, the contact collision during the magnetic adsorption between the wedge-shaped locking tongue 33 and the magnetic conductive plate 322 can be reduced, the damage of both can be prevented, and the service life of the structure is increased.

[0063] In this embodiment, it further includes a visualization display unit. The visualization display unit includes a flexible electronic paper display screen 50 and a three-color LED warning light, and the electronic paper display screen 50 can display the pressure distribution cloud map in real time.

[0064] In this way, the user can view the data of the pressure detection unit through the visualization display unit, improving the practicability. When the data is abnormal, the alarm unit can emit an alarm sound through the three-color LED warning light.

[0065] In this embodiment, in step S6, the three-color LED warning light switches the display mode according to the severity of the leakage: when the probability is >90%, it flashes red (2Hz), and when the probability is 70-90%, it lights yellow constantly;

[0066] The electronic paper display screen 50 generates a pressure gradient cloud map and marks the leakage hot spot area.

[0067] Example of the working process, step 1: Leakage trigger

[0068] When there is a leakage hole with a diameter of 1.2 mm in the pipeline:

[0069] The differential pressure sensor 40 detects a sudden change in the differential pressure on both sides of the leakage point (ΔP = 0.37 MPa); the ultrasonic sensor captures the acoustic emission signal in the characteristic frequency band of 20 - 50 kHz;

[0070] Step 2: Data processing

[0071] The signal amplification circuit amplifies the original signal to the range of 0 - 5V, the FIR filter removes the pump valve vibration noise (the main frequency band > 500 Hz), the pattern recognition module calculates the leakage probability up to 92.7%, and the positioning error is ±11 cm;

[0072] Step 3: Execution response

[0073] The three - color LED switches to the red flashing mode (frequency 2 Hz), sends an alarm message to the monitoring center through NB - IoT, and the electronic paper display screen 50 generates a pressure gradient cloud map to mark the leakage area.

[0074] In this embodiment, it further includes a redundant detection unit. The redundant detection unit includes an ultrasonic sensor and an infrared thermal imager, and the detection data of both are fused with the data of the pressure detection unit;

[0075] Redundant verification step S5: When the pressure detection unit determines leakage, start the ultrasonic sensor to detect the acoustic emission signal in the frequency band of 20 - 50 kHz; the infrared thermal imager scans the surface temperature distribution of the pipeline; when the three - source data is consistent, confirm the leakage event. In this way, the diversity of pipeline detection can be improved, and the three independent detection technologies can also be used alone.

[0076] Ultrasonic sensor: Adopt Olympus Panametrics NDT type, center frequency 1 MHz;

[0077] Infrared thermal imager: FLIR A315, temperature measurement range - 20 ~ 150 °C, spatial resolution 1.3 mrad.

[0078] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A pipeline pressure leakage detection method, characterized in that: The following steps are involved: S1. The installation base is closed around the pipeline to be tested and mechanically fixed by a quick locking structure; the installation base is provided with a pressure detection unit, a signal processing unit, an alarm unit and a wireless transmission module; S2. An adaptive adjustment mechanism is provided on the inner side of the mounting base, and the adaptive adjustment mechanism automatically adjusts the detection gap according to the pipeline temperature; S3, the pressure detection unit comprises at least three differential pressure sensors distributed along the circumference of the pipe body; the differential pressure sensor array continuously collects the circumferential pressure gradient data of the pipeline; S4, the signal processing unit includes a signal amplification circuit, a FIR digital filter and a pattern recognition module; the signal processing unit performs temperature compensation and noise filtering processing; S5, the pattern recognition module determines the leakage event and calculates the positioning coordinates based on the convolutional neural network; S6. The alarm unit triggers an audible and visual alarm and sends a wireless alarm signal.

2. The pipeline pressure leakage detection method according to claim 1, characterized in that: In the step S1, the pressure detection unit further includes a temperature compensation module, and the temperature compensation module includes NTC thermistors symmetrically arranged on both sides of the differential pressure sensor.

3. The pipeline pressure leakage detection method according to claim 2, characterized in that: In step S3, the differential pressure sensor uses a MEMS piezoresistive sensor, which is arranged in a circular array at intervals of 120°, and a detection gap of 0.5-2 mm is formed between the detection surface of each sensor and the pipe wall; the detection surface of the differential pressure sensor is provided with a nano-hydrophobic coating.

4. The pipeline pressure leakage detection method according to claim 3, characterized in that: In step S2, the adaptive adjustment mechanism includes a memory alloy spring, a sliding guide rail and a sensor bracket for installing a differential pressure sensor, the sliding guide rail is arranged parallel to the inner wall of the mounting base along the circumferential direction, the sensor bracket slides with the sliding guide rail, one end of the memory alloy spring is inserted into the inner wall of the mounting base, and the other end of the memory alloy spring is pressed against the sensor bracket; the sensor bracket is connected to the memory alloy spring through a hinge ball head.

5. The pipeline pressure leakage detection method according to claim 1, characterized in that: In the step S1, a contact gasket is provided on the mounting base. The contact gasket is a half-moon-shaped structure and is fixed to the open end of the mounting base by pre-tightening bolts. The inner surface of the contact gasket is provided with a silicone rubber sealing layer.

6. The pipeline pressure leakage detection method according to claim 1, characterized in that: The mounting base adopts a segmented buckle structure, and the mounting base includes an upper half ring and a lower half ring that are symmetrically arranged; the quick locking structure includes a spring steel sheet and a magnetic fastener, and the spring steel sheet is a double-bent sheet structure, the root of the spring steel sheet is fixed to the inner side of the upper half ring, and the free end of the spring steel sheet is provided with a wedge-shaped lock tongue; The magnetic fastener consists of a permanent magnet and a magnetic conductive plate. The permanent magnet is embedded in the groove of the lower half ring, and the magnetic conductive plate is installed on the top of the permanent magnet. A positioning groove is formed in the magnetic conductive plate. The wedge-shaped lock tongue is inserted in the positioning groove and magnetically cooperates with the magnetic conductive plate.

7. The pipeline pressure leakage detection method according to claim 6, characterized in that: The contact surface between the magnetic conductive plate and the wedge-shaped lock tongue is provided with a silicone rubber buffer layer.

8. The pipeline pressure leakage detection method according to any one of claims 1 to 7, characterized in that: It also includes a visual display unit, which includes a flexible electronic paper display screen and a three-color LED warning light. The electronic paper display screen can display a pressure distribution cloud map in real time.

9. The pipeline pressure leakage detection method according to claim 8, characterized in that: In step S6, the three-color LED warning light switches the display mode according to the severity of the leakage: red flashing (2Hz) when the probability is greater than 90%, and yellow always on when the probability is 70-90%; The electronic paper display screen generates a pressure gradient cloud map and marks the leakage hot spot area.

10. The pipeline pressure leakage detection method according to any one of claims 1 to 7, characterized in that: It also includes a redundant detection unit, which includes an ultrasonic sensor and an infrared thermal imager, and the detection data of the two are fused with the pressure detection unit; Redundancy verification step S5: when the pressure detection unit determines that there is a leak, the ultrasonic sensor is started to detect the acoustic emission signal in the 20-50kHz frequency band; the infrared thermal imager scans the temperature distribution on the pipeline surface; and the leak event is confirmed when the three-source data are consistent.

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