A pipeline inner wall scale detector, detection system and detection method

Abstract

The present application relates to the technical field of pipeline fouling detection, and particularly relates to a pipeline inner wall fouling detector, a detection system and a detection method, aiming to solve the problem of high detection time and labor cost of existing pipeline fouling detection. The pipeline inner wall fouling detector comprises a spherical shell, a first hydrophone, a second hydrophone, a counterweight, a circuit board and a power supply unit; the first hydrophone and the second hydrophone are installed on the spherical shell; the axes of the two shock absorbers are collinear with the Z-axis, and the two shock absorbers are sleeved on the spherical shell and symmetrically arranged on the two sides of the equatorial plane; the circuit board and the power supply unit are installed in the inner cavity of the spherical shell, and an acceleration sensor is arranged on the circuit board. The characteristics of the fluid pushing the spherical detector to roll along the detected pipeline, the increased flow rate at the pipeline fouling position, the change in the frequency and regularity of the acceleration signal and the acoustic noise generated by the rolling of the spherical detector at the fouling position are used to determine the fouling section and determine the position, so that automatic monitoring is realized, the detection efficiency is greatly improved, and the labor cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of pipe internal scaling detection technology, and in particular to a pipe internal scaling detector, detection system and detection method. Background Technology

[0002] Pipelines are the most economical and efficient way to continuously transport liquid resources such as crude oil and petroleum products, as well as gaseous resources such as natural gas. However, oil and gas transported over long distances contain impurities such as organic matter, hydrogen sulfide, and carbon dioxide. Under the influence of high temperature and high pressure, these impurities will evaporate and concentrate, and undergo chemical reactions to precipitate insoluble crystals, which will then form scale on the inner wall of the pipeline, reducing the inner diameter of the pipeline. In severe cases, this can cause pipeline blockage, leading to casualties and economic losses.

[0003] Currently, direct methods are commonly used for scale detection, which involve measuring the thickness of furnace tubes or vessel walls using thickness gauges (such as ultrasonic thickness gauges). However, due to the significant difference in acoustic impedance between the scale layer and the pipe body, ultrasonic waves undergo multiple reflections and refractions inside the pipe wall, making it difficult for them to penetrate the scale layer. In addition, ultrasonic guided waves and acoustic resonance methods are also used for non-destructive testing of pipe inner walls. However, these methods typically require point-to-point measurements of each pipe section, resulting in high time and labor costs and inconvenient construction. Summary of the Invention

[0004] The purpose of this invention is to provide a pipe internal wall scaling detector, detection system and detection method to solve the problems of high time and labor cost in existing pipe scaling detection.

[0005] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows: A pipe internal wall scaling detector includes a spherical shell, a first hydrophone, a second hydrophone, a counterweight, a shock-absorbing ring, a circuit board, and a power supply unit. The first and second hydrophones are mounted on the spherical shell. The first hydrophone is located on the equatorial plane of the spherical shell, with the Z-axis being an axis perpendicular to the equatorial plane and passing through the center of the spherical shell. The second hydrophone is located on the Z-axis. The counterweight is aligned with the equatorial plane and mounted inside the spherical shell, which rolls around the Z-axis. The axis of the shock-absorbing ring is collinear with the Z-axis, and the two shock-absorbing rings are fitted onto the spherical shell and symmetrically arranged on both sides of the equatorial plane. The circuit board and the power supply unit are mounted inside the spherical shell, and an acceleration sensor is mounted on the circuit board.

[0006] Furthermore, the pipe inner wall scaling detector also includes a suspension unit, which includes a suspension ball and a suspension support; the suspension ball is connected above the suspension support, and the suspension support is rotatably connected to the ball shell with the rotation axis being the Z-axis; a pin is provided on the suspension support, and the pin abuts against the damping ring to tilt the damping ring.

[0007] Furthermore, the power supply unit includes a battery and a wireless charging coil, the wireless charging coil being connected to the battery, which is used to power the circuit board, the first hydrophone, and the second hydrophone.

[0008] Furthermore, a power regulator module is also installed on the circuit board, which is connected to the battery.

[0009] Furthermore, the spherical shell includes an upper shell and a lower shell. The second hydrophone and circuit board are mounted in the upper shell, while the battery and wireless charging coil are mounted in the lower shell.

[0010] Furthermore, a magnetometer is also installed on the circuit board.

[0011] Furthermore, the circuit board is also equipped with an MCU, an onboard flash memory module, and a wireless transmission module; the MCU is connected to the first hydrophone, the second hydrophone, the accelerometer, the onboard flash memory module, and the wireless transmission module.

[0012] Furthermore, the ratio of the rotational inertia of the detector's Z-axis to X-axis is k, where k ∈ [1.1, 1.9].

[0013] In another aspect, the present invention provides a pipe inner wall scaling detection system, including the above-mentioned pipe inner wall scaling detector, and further including an external magnetic field, wherein multiple external magnetic fields are spaced apart along the length of the pipe.

[0014] A third aspect of the present invention provides a method for detecting scale buildup on the inner wall of a pipe, employing the aforementioned pipe inner wall scale detector, comprising the following steps: Signal acquisition: The scale detector on the inner wall of the pipe is placed into the pipe and rolled along the pipe under the action of water flow. The first hydrophone and the second hydrophone collect the sound signal, and the accelerometer collects the acceleration signal. Data analysis: The acceleration signal of the pipe inner wall scaling detector is a sinusoidal signal, and the frequency of the sinusoidal signal in the scaling section is greater than that in the non-scaling section; at the same time, the pipe inner wall scaling detector generates noise signals when entering and exiting the scaling section, which are used to determine whether there is scaling and diameter change; when the surface of the scaling section is uneven, the amplitude of the acceleration signal in the scaling section is greater than that in the non-scaling section or the integrity of the acceleration signal waveform is destroyed, showing a non-sinusoidal shape.

[0015] In summary, the technical effects achieved by this invention are as follows: The pipe internal wall scaling detector provided by this invention includes a spherical shell, a first hydrophone, a second hydrophone, a counterweight, a circuit board, and a power supply unit. The first and second hydrophones are installed on the spherical shell. The first hydrophone is located on the equatorial plane of the spherical shell, with the axis perpendicular to the equatorial plane and passing through the center of the spherical shell as the Z-axis. The second hydrophone is located on the Z-axis. The counterweight is aligned with the equatorial plane and installed in the inner cavity of the spherical shell, and the spherical shell rolls around the Z-axis. The axis of the damping ring is collinear with the Z-axis, and the two damping rings are fitted onto the spherical shell and symmetrically arranged on both sides of the equatorial plane. The circuit board and the power supply unit are installed in the inner cavity of the spherical shell, and an acceleration sensor is provided on the circuit board.

[0016] The pipe scaling detector provided by this invention utilizes fluid to propel the detector along the inspected pipe for automatic pipe inspection, eliminating the need for manual segment-by-segment inspection. A counterweight causes the spherical detector to roll along a fixed axis. Taking advantage of the increased flow velocity at the scaling point and the acoustic noise generated by the rolling of the sphere, a first hydrophone, a second hydrophone, and an accelerometer detect acoustic and acceleration signals. The location of the scaling section is determined by analyzing the frequency and regularity of the acceleration signal and the characteristics of the acoustic noise generated by the detector's rolling motion. The internal counterweight combined with an external shock-absorbing ring avoids the need for an elastic coating layer covering the spherical shell and external counterweight, reducing the detector's diameter, improving throughput, and facilitating passage through scaling sections to ensure successful inspection. Simultaneously, the elastic coating layer avoids obstructing the acoustic signal, improving the quality of acoustic signal acquisition.

[0017] Compared to manual, segment-by-segment, point-by-point inspection, the pipe internal wall scaling detector only requires fluid propulsion, offering advantages such as simple operation and high efficiency, which can greatly reduce inspection costs. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A cross-sectional schematic diagram of a pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 2 A three-dimensional schematic diagram of a pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 3 This is an exploded view of a pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 4 A schematic diagram of the coordinate axes of a pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the upper shell structure; Figure 6 This is a schematic diagram of the lower shell structure; Figure 7 This is a connection diagram of electrical components; Figure 8 This is a schematic diagram of the rolling of a pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 9 This is a schematic diagram of the operation of the pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of the time-domain variation of the Y-axis acceleration of the pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 11 This is a schematic diagram showing the flow velocity changes in the scaling section of the pipeline. Figure 12 A schematic diagram illustrating the changes in acoustic signals collected by the pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 13 This is another structural schematic diagram of the pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 14 The left view of the pipe inner wall scaling detector provided in an embodiment of the present invention; Figure 15 This is a schematic diagram of the levitation unit. Figure 16 Acceleration data of the pipe inner wall scaling detector in the non-scaling section provided in the embodiments of the present invention; Figure 17 The acceleration data of the pipe inner wall scaling detector in the scaling section provided in the embodiments of the present invention; Figure 18 The time-frequency diagram of the acceleration signal collected by the accelerometer in the non-scalded section during actual use of the pipe inner wall scaling detector provided in this embodiment of the invention; Figure 19 The time-frequency diagram of the acceleration signal collected by the accelerometer in the scaling section during actual use of the pipe inner wall scaling detector provided in this embodiment of the invention; Figure 20 The sound collected by the microphone during actual use of the pipe inner wall scaling detector provided in this embodiment of the invention; Figure 21 The time-frequency diagram of the sound signal collected by the microphone during actual use of the pipe inner wall scaling detector provided in this embodiment of the invention.

[0020] Icons: 100-Spherical shell; 200-First hydrophone; 300-Second hydrophone; 400-Counterweight; 500-Shock absorber ring; 600-Circuit board; 700-Power supply unit; 800-Suspension unit; 900-Adapter ring; 110-Upper shell; 120-Lower shell; 111-Upper mounting bracket; 112-Mounting hole; 121-Lower mounting bracket; 710-Battery; 720-Wireless charging coil; 810-Suspension ball; 820-Suspension bracket; 830-Magnet; 821-Pin; 822-Connecting ring. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0023] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0024] Currently, the direct method is commonly used for scale detection, which involves measuring the thickness of the furnace tube or vessel wall using a thickness measuring instrument. However, due to the significant difference in acoustic impedance between the scale layer and the pipe body, ultrasonic waves undergo multiple reflections and refractions inside the pipe wall, making it difficult for them to penetrate the scale layer. In addition, ultrasonic guided waves and acoustic resonance methods are also used for non-destructive testing of pipe inner walls. However, these methods typically require point-to-point measurements of each pipe section, resulting in high time and labor costs and inconvenient construction.

[0025] In view of this, the present invention provides a pipe inner wall scaling detector, including a spherical shell 100, a first hydrophone 200, a second hydrophone 300, a counterweight 400, a circuit board 600, and a power supply unit 700; the first hydrophone 200 and the second hydrophone 300 are installed on the spherical shell 100, the first hydrophone 200 is located on the equatorial plane of the spherical shell 100, with the axis perpendicular to the equatorial plane and passing through the center of the spherical shell 100 as the Z-axis, and the second hydrophone 300 is located on the Z-axis; the counterweight 400 is overlapped with the equatorial plane and installed in the inner cavity of the spherical shell 100, and the spherical shell 100 rolls around the Z-axis; the axis of the damping ring 500 is collinear with the Z-axis, and the two damping rings 500 are fitted onto the spherical shell 100 and symmetrically arranged on both sides of the equatorial plane; the circuit board 600 and the power supply unit 700 are installed in the inner cavity of the spherical shell 100, and an acceleration sensor is provided on the circuit board 600.

[0026] The pipe scaling detector provided by this invention utilizes fluid to propel the detector along the pipe being inspected, automatically completing the pipe inspection without the need for manual segment-by-segment inspection. A counterweight 400 causes the spherical detector to roll along a fixed axis. Utilizing the increased flow velocity at the scaling point and the acoustic noise generated by the rolling of the ball at the scaling point, combined with the detection of acoustic and acceleration signals by a first hydrophone 200, a second hydrophone 300, and an accelerometer, the scaling section is identified and its location determined by the frequency and regularity changes in the acceleration signal and the characteristics of the acoustic noise generated by the detector's rolling at the scaling point. The internal design of the counterweight 400 combined with an external shock-absorbing ring 500 avoids the need for an elastic wrapping layer covering the spherical shell 100 and an external counterweight, reducing the detector's diameter, improving throughput, and facilitating passage through the scaling section to ensure successful inspection. Simultaneously, it avoids the elastic wrapping layer obstructing the acoustic signal, improving the quality of acoustic signal acquisition.

[0027] Compared to manual, segment-by-segment, point-by-point inspection, the pipe internal wall scaling detector only requires fluid propulsion, offering advantages such as simple operation and high efficiency, which can greatly reduce inspection costs.

[0028] The following combination Figures 1-21 The structure and shape of the pipe inner wall scaling detector provided in this embodiment are described in detail: In this embodiment, the equatorial plane of the spherical shell 100 is taken as the XOY plane, and the center of the spherical shell 100 is taken as point O, as follows: Figure 4 , Figure 8 As shown, the scale detector on the inner wall of the pipe rolls around a fixed axis (Z-axis). Specifically, to ensure fixed-axis rolling and that the fluid can smoothly push the detector, the ratio of the moment of inertia of the detector's Z-axis to X-axis is k, k∈[1.1, 1.9]. Preferably, k is 1.5 to ensure stable rolling while avoiding excessive weight, which would prevent the fluid from pushing the detector through the scaled section or the slope section.

[0029] Specifically, the counterweight 400 is made of tungsten metal and is disc-shaped to ensure uniform mass. The axis of the counterweight 400 is collinear with the Z-axis so that the detector rolls around the Z-axis. Figure 8 As shown. Furthermore, symmetrical through holes are provided on the counterweight 400 to facilitate wiring. Because the detector's Z-axis moment of inertia is greater than its Y-axis and X-axis moments of inertia, the detector rolls stably around a fixed axis Z in the pipe. Therefore, the speed and distance of the detector's rolling motion can be inferred from the periodic changes in the acceleration signal along the Z and Y axes.

[0030] In this embodiment, the power supply unit 700 includes a battery 710 and a wireless charging coil 720. The wireless charging coil 720 is connected to the battery 710. The battery 710 supplies power to the circuit board 600, the first hydrophone 200, and the second hydrophone 300. Charging the battery 710 via the wireless charging coil 720 avoids disassembling the spherical shell 100, maintaining the sealing and smoothness of the spherical shell 100. It also prevents eddies from forming on the surface of the spherical shell 100 when fluid pushes it, thus avoiding noise and reducing the rolling of the spherical shell 100. This ensures the sound signal acquisition quality and detection efficiency of the first hydrophone 200 and the second hydrophone 300. The battery 710 is a lithium battery to ensure energy density, reduce its weight, and facilitate the adjustment of the rotational inertia by the counterweight 400.

[0031] In this embodiment, the spherical shell 100 includes an upper shell 110 and a lower shell 120, as follows: Figure 5 , Figure 6 As shown, an upper fixing bracket 111 is provided inside the upper shell 110 for fixing the circuit board 600; a lower fixing bracket 121 is provided inside the lower shell 120 for fixing the battery 710, and a wireless charging coil 720 is installed on the top of the lower shell 120. Furthermore, a mounting hole 112 is provided at the top of the upper shell 110 for installing a second hydrophone 300; a groove is provided at the joint between the upper shell 110 and the lower shell 120 to form a rectangular hole for installing a first hydrophone 200. The arrangement of the first hydrophone 200 and the second hydrophone 300 ensures comprehensive acquisition of sound signals. In this embodiment, ultraviolet-cured adhesive is used to seal the joint between the upper shell 110 and the lower shell 120, as well as the mounting positions of the first hydrophone 200 and the second hydrophone 300, to ensure the waterproof performance of the detector.

[0032] In this embodiment, the shock-absorbing ring 500 can be made of rubber, and an O-ring can be selected. Correspondingly, annular grooves are provided on both the upper shell 110 and the lower shell 120 for installing the shock-absorbing ring 500. The first hydrophone 200 is disposed between the two shock-absorbing rings 500. When rolling, the shock-absorbing ring 500 contacts the inner wall of the pipe, which can protect the first hydrophone 200 and prevent the spherical shell 100 from directly contacting the pipe, thus avoiding acoustic signal interference. This makes it difficult to distinguish the acoustic signal of the scaled section from the non-scaled section, and at the same time avoids the acoustic signal generated when passing through the scaled section being too large, resulting in abnormal signals and making it impossible to accurately determine the length of the scaled section.

[0033] In this embodiment, the circuit board 600 is also equipped with a power supply regulator module, a magnetometer, an MCU, an onboard flash memory module, and a wireless transmission module, such as... Figure 7 As shown, the power supply regulator module is connected to the battery 710 and is used to provide stable power to the magnetometer, MCU, onboard flash memory module, wireless transmission module, accelerometer, first hydrophone 200, and second hydrophone 300. The MCU is connected to the first hydrophone 200, second hydrophone 300, accelerometer, onboard flash memory module, and wireless transmission module.

[0034] An accelerometer collects acceleration signals, a first hydrophone 200 and a second hydrophone 300 collect acoustic signals, and a magnetometer collects magnetic field signals. The MCU acquires the acceleration, acoustic, and magnetic field signals and writes the signal data into the onboard flash memory module. The wireless transmission module receives commands and transmits data so that the host computer can read the signal data and control the detectors. The wireless transmission module can use devices such as a Wi-Fi antenna or Bluetooth.

[0035] In this embodiment, a triaxial accelerometer is selected as the accelerometer to accurately analyze acceleration data, or three accelerometers are used for data acquisition.

[0036] The working process of the pipe inner wall scaling detector provided in this embodiment is as follows: The detector is placed at the beginning of the pipeline, allowing it to roll along a fixed axis under the propulsion of the water flow. Simultaneously, the host computer transmits a working command via a wireless transmission module to activate the detector. Upon receiving the command, the MCU begins operation, sampling data from the accelerometer and magnetometer at a 1000Hz sampling rate to obtain the acceleration signal during detector rolling and the magnetic signal in the environment. It also samples data from the hydrophone at an 8kHz sampling rate to obtain the surrounding acoustic signal, thus performing data acquisition and reading. Simultaneously, the MCU writes the collected data to the onboard flash memory module for storage. A ball-collecting net is placed at the detection endpoint to block the detector, allowing for targeted retrieval. After the detector reaches the endpoint, the host computer reads the data via the wireless transmission module and shuts down the detector. Data analysis is then performed; by plotting the accelerometer's spectrum and the acoustic signal waveform, the signal location of the scaled section in the pipeline can be found. Combining this with the number of rolling cycles from the accelerometer and the magnetic field strength collected by the magnetometer, mileage and pipe segment location can be determined, identifying the pipe segment where scale has occurred. Figure 9 As shown, the area within the dashed rectangle is the scaled section.

[0037] Specifically, such as Figure 11 As shown, the fluid velocity increases in the scaling section. The pipe inner diameter is 100mm, and the scaling section inner diameter is 80mm. Correspondingly, the detector's rolling speed also increases, and consequently, the detector's acceleration signal frequency increases. Figure 10 As shown, the area marked by the dashed line between 44 and 46 seconds corresponds to the scaling section. Here, the detector's rolling speed increases, and the frequency of its periodic acceleration changes increases. That is, when the detector performs stable fixed-axis rolling, its acceleration signal is a sinusoidal signal, and the acceleration signal frequency in the scaling section is greater than that in the non-scaling section. When the detector encounters an uneven surface, it will produce unstable fixed-axis rolling, disrupting the integrity of its acceleration signal waveform. The amplitude of the acceleration signal is greater than that in the non-scaling section, or the degree of disorder in the acceleration signal is greater than that in the non-scaling section, indicating that bumps have occurred, and scaling can be identified here. After calculating the speed from the frequency, the cross-sectional area can be calculated, and then the thickness of the scaling can be estimated. The disorder in the acceleration signal, as reflected in the waveform, means that the fundamental sinusoidal frequency component of the rolling signal is affected by other frequency components, causing spikes or waves in the waveform, making the waveform no longer smooth. The denser the spikes on the waveform, the greater the degree of disorder. Figure 10 The waveform in the area marked by the two dashed lines is caused by the uneven surface of the scaled section, i.e., many pits and depressions.

[0038] In addition, a noticeable acoustic signal is generated when the detector enters and exits the scaling section, such as... Figure 12As shown, the amplitude of the acoustic signal increases significantly at 1 second and 3 seconds. This is because at 1 second, the detector collides with the scale when entering the scaling zone, generating noise. Simultaneously, the increased flow velocity pushes the detector, creating pressure between the fluid and the detector, thus enhancing the acoustic signal. At 3 seconds, the detector leaves the scaling zone, experiencing a smaller collision than at 1 second, resulting in a relatively smaller acoustic signal amplitude. At the same time, the decreased fluid velocity obstructs the detector, creating pressure between the fluid and the detector, further enhancing the acoustic signal. In other words, the delay in detector velocity change compared to the slower fluid velocity change leads to increased thrust or resistance from the fluid, resulting in increased friction between the detector and the pipe wall, as well as between the liquid and the detector. This, combined with the impact between the liquid and the detector, causes a significant change in the acoustic signal when the detector enters and exits the scaling zone. Furthermore, the high-shift in the acoustic signal spectrum and the generally increased amplitude across all frequencies also indicate the presence of scaling. Figure 16 , Figure 17 The image shows a comparison of acceleration data between the non-scaling and scaling sections. Figure 17 The scaling phase occurs between 2.5 and 4 seconds. During this phase, the waveform undergoes significant changes, with a higher frequency and more burrs on the waveform. Correspondingly, such as... Figure 18 , Figure 19 As shown, in addition to the higher low-frequency sinusoidal energy generated by rolling in the scaled section, the energy at other high-frequency locations is significantly higher than that in the non-scaled section.

[0039] That is, by analyzing the acceleration signal, the position and length of the scaling section can be calculated, and the position and length of the scaling section can be confirmed based on the acoustic signal, eliminating interference signals during the rolling process and avoiding misjudgment.

[0040] Without using the 500 shock absorber ring, the detector will continuously generate noise signals as it rolls along the pipeline, making it impossible to accurately distinguish between scaled and non-scaled sections, and also impossible to accurately determine the length of the scaled section, which will interfere with the determination of the scaled section.

[0041] In addition, the geomagnetic field will change under the magnetic shielding effect of different pipeline sections, and the changes will be different for different pipelines. The magnetometer can perform mileage positioning and pipeline positioning by collecting the magnetic field strength, which can help determine the location.

[0042] The pipe internal wall scaling detector provided in this embodiment utilizes the fixed-axis stable rolling characteristics and the changes in fluid flow velocity and acoustic characteristics caused by pipe scaling to achieve low-cost, small-volume pipe scaling detection and location. Furthermore, by incorporating wireless charging and wireless communication, it can be assembled without the need for secondary opening, ensuring its waterproofness.

[0043] In an optional embodiment, to avoid the damping ring 500 obstructing signal acquisition and to reduce the squeezing of the pipe inner wall on the damping ring 500 to reduce interference signals, the pipe inner wall scaling detector also includes a suspension unit 800, such as... Figure 13 As shown. Specifically, the levitation unit 800 includes a levitation ball 810 and a levitation support 820, as... Figure 15 As shown, the suspended ball 810 is connected above the suspended support 820, and the suspended support 820 is rotatably connected to the spherical shell 100, with the rotation axis being the Z-axis. The suspended support 820 is equipped with two ejector pins 821, each located on one side of a shock-absorbing ring 500 facing away from each other and abutting against the shock-absorbing ring 500. The suspended ball 810 and the suspended support 820 are connected by a steel wire rope. Alternatively, the suspended ball 810 can be directly fixed to the top of the support, thus keeping the suspended support 820 relatively fixed and preventing it from rolling with the spherical shell 100. A connecting ring 822 is provided on the suspension bracket 820 to avoid the second hydrophone 300 located on the Z-axis of the spherical shell 100, so as to avoid interference with the second hydrophone 300. To ensure smooth rotation of the spherical shell 100 and the suspension bracket 820, a thrust bearing can be provided to connect the shell 100 and the suspension bracket 820, or a hollow shaft can be provided on the spherical shell 100. The hollow shaft is inserted into the connecting ring 822 and a rolling bearing is provided between the two. The second hydrophone 300 is installed inside the hollow shaft.

[0044] When the first hydrophone 300 rolls to the bottom, its limited space near the inner wall of the pipe makes it prone to generating interference signals such as echoes. Therefore, a pin 821 is installed on the suspension bracket 820. Simultaneously, the width of the annular grooves on the upper shell 110 and lower shell 120 is greater than that of the damping ring 500 to ensure that the damping ring 500 can swing along the Z-axis. By limiting the position of the damping ring 500 with the pin 821, the two damping rings 500 can maintain a state where the upper distance is smaller and the lower distance is larger, such as... Figure 14As shown, this provides ample space when the first hydrophone 300 is positioned below, reducing interference signals caused by factors such as echoes. Furthermore, to ensure the stability of the damping ring 500, adapter rings 900 are provided. Two adapter rings 900 are respectively installed in annular grooves on the upper half-shell 110 and the lower half-shell 120. The damping ring 500 is installed on the adapter rings 900, which have corresponding annular grooves. A pin 821 abuts against the side of the adapter ring 900 to keep it tilted. To reduce friction, a ball bearing can be provided at the end of the pin 821. Furthermore, to maintain the stability of the tilted state of the adapter ring, the suspension unit 800 also includes a magnet 830. The magnet 830 is connected to the suspension bracket 820 to attract the adapter ring 900, thereby maintaining the tilted state of the adapter ring 900 through the cooperation of the pin 821 and the magnet 830. In addition, ejector pins 821 can be provided on both sides of the adapter ring 900, and the two ejector pins 821 have different heights, so that the adapter ring 900 can be kept in an inclined state.

[0045] During operation, driven by the spherical shell 100 and buoyed by the suspended ball 810, the suspended support 820 moves along the length of the pipe in a stable posture, while the ejector pin 821 keeps the damping ring 500 in a figure-eight shape. The suspension unit 800 reduces the deformation of the damping ring 500 and its friction with the inner wall of the pipe, thereby reducing interference signals caused by friction and collision. At the same time, the figure-eight shape reduces the interference of echo signals, making signal acquisition more accurate.

[0046] Based on the pipe internal wall scaling detector proposed in this embodiment, a pipe internal wall scaling detection system is proposed, including the aforementioned pipe internal wall scaling detector and an external magnetic field, with multiple external magnetic fields spaced apart along the length of the pipe. Specifically, multiple magnets are spaced apart along the length of the pipe to form a magnetic field. When the detector passes through the magnetic field, the change in the magnetic field signal can be measured, thereby accurately determining the position parameters of the detector's current position. The point-distributed magnetic field can greatly improve the positioning accuracy, which is beneficial for more accurate determination of the location and length of the scaling section and eliminates the cumulative error caused by the pipe length.

[0047] Based on the pipe internal wall scaling detector proposed in this embodiment, a method for detecting pipe internal wall scaling is proposed. Using the aforementioned pipe internal wall scaling detector, the method includes the following steps: Signal acquisition: The scale detector on the inner wall of the pipe is placed into the pipe and rolled along the pipe under the action of water flow. The first hydrophone 200 and the second hydrophone 300 collect the sound signal, and the accelerometer collects the acceleration signal. Data Analysis: The acceleration signal from the rolling of the scale detector on the inner wall of the pipeline is a sinusoidal signal, with a higher frequency in the scaled section than in the non-scaled section. Simultaneously, the scale detector generates noise signals as it moves in and out of the scaled section, used to determine if there is scaling or a change in diameter. When the surface of the scaled section is uneven, the fixed-axis rolling of the scale detector becomes unstable, affecting the acceleration signal. This results in an acceleration signal amplitude greater than that in the non-scaled section or a disruption of the waveform's integrity, manifesting as a non-sinusoidal shape. During stable rolling, the acceleration signal waveform is smooth. When the waveform integrity is disrupted, spikes or waves appear. The denser the spikes or waves, the greater the unevenness of the scaled section. Waveform integrity disruption also occurs in the non-scaled section, but its density is less than in the scaled section.

[0048] Furthermore, due to the long span of actual pipelines, the signal length obtained after the detector is running is too long. Using traditional spectrum analysis methods in this case would lead to increased computational load, and manually locating the scale signal is also time-consuming. By combining a deep learning model, using a one-dimensional CNN network with an LSTM network, the original signal is detected after training, enabling rapid location of the scale signal and increasing detection speed.

[0049] Specifically, the dataset used for model training consists of manually labeled signal segments, categorized into three types: no pipe diameter change detected within the signal, pipe diameter decreasing from large to small, and pipe diameter increasing from small to large. These three signal segments represent no scaling, entering a scaling zone, and moving away from a scaling zone, respectively. After model training is complete, a sliding window approach can be used to traverse all signals over long-duration acoustic signals and pinpoint the time periods in which scaling occurs.

[0050] In addition, the acceleration spectrum can be analyzed for further judgment. A higher acceleration frequency or a greater amount of non-sinusoidal energy indicates scaling. After inferring the velocity from the frequency, the flow cross-sectional area can be calculated to estimate the thickness of the scaling. Simultaneously, the sound spectrum can be analyzed for further judgment. A high-shifted spectrum with generally increased amplitude across all frequencies also indicates scaling. Figure 20 , Figure 21 As shown, between 710 and 712 seconds, both the acceleration and acoustic signals changed significantly, indicating that scaling had occurred at this point.

[0051] The pipe internal wall scaling detector provided in this embodiment has the following advantages: 1. Compared to manual segment-by-segment and point-by-point inspection, using a small-diameter spherical detector that rolls along the pipeline under the propulsion of the fluid is simple to operate and has high inspection efficiency.

[0052] By utilizing the thrust, friction, and acoustic signals generated by the flow velocity changes as the fluid propels the detector into and out of the scaling section, the scaling section can be identified. This helps to avoid abnormal changes in the detector's acceleration due to fluid fluctuations and other factors, which could lead to misjudgments and cause non-scaling sections to be identified as scaling sections, resulting in unnecessary losses.

[0053] The method of estimating scale thickness by detecting changes in detector acceleration is more accurate than methods such as ultrasound, and can avoid interference caused by ultrasonic refraction and reflection.

[0054] 2. Once sealed, the detector does not need to be opened. It can be powered wirelessly and transmit data and commands wirelessly, making it convenient to use.

[0055] 3. The weight distribution of the detector is designed to satisfy the fixed-axis rolling condition, and the rolling speed of the ball is used to determine the scaled pipe section. The judgment condition is intuitive and quick.

[0056] 4. Deep learning is used to perform traversal analysis of acceleration signals, eliminating the need for manual searching and resulting in high data processing efficiency.

[0057] 5. The detector has high space utilization, small size and abundant sensors in the spherical shell 100. Therefore, it does not have high requirements for the inner diameter of the pipe and has good passability. It is not easy to get stuck when entering the scaling section.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pipe inner wall scaling detector, characterized in that, It includes a spherical shell (100), a first hydrophone (200), a second hydrophone (300), a counterweight (400), a shock absorber (500), a circuit board (600), and a power supply unit (700). The first hydrophone (200) and the second hydrophone (300) are mounted on the spherical shell (100). The first hydrophone (200) is located on the equatorial plane of the spherical shell (100), with the axis perpendicular to the equatorial plane and passing through the center of the spherical shell (100) as the Z-axis. The second hydrophone (300) is located on the Z-axis. The counterweight (400) is aligned with the equatorial plane and installed in the inner cavity of the spherical shell (100), enabling the spherical shell (100) to roll around the Z-axis; The axis of the damping ring (500) is collinear with the Z-axis, and the two damping rings (500) are fitted onto the spherical shell (100) and symmetrically arranged on both sides of the equatorial plane; The circuit board (600) and the power supply unit (700) are installed in the inner cavity of the spherical shell (100), and an acceleration sensor is provided on the circuit board (600); A magnetometer is also provided on the circuit board (600); The ratio of the rotational inertia of the detector's Z-axis and X-axis is k, k∈[1.1, 1.9].

2. The pipe inner wall scaling detector according to claim 1, characterized in that, It also includes a suspension unit (800), which includes a suspension ball (810) and a suspension support (820). The suspended ball (810) is connected above the suspended support (820), and the suspended support (820) is rotatably connected to the spherical shell (100), with the rotation axis being the Z-axis; The suspension bracket (820) is provided with a pin (821), which abuts against the shock absorber (500) to tilt the shock absorber (500).

3. The pipe inner wall scaling detector according to claim 2, characterized in that, The two ejector pins (821) are respectively disposed on opposite sides of the two damping rings (500) and abut against the damping rings (500).

4. The pipe inner wall scaling detector according to claim 1, characterized in that, The power supply unit (700) includes a battery (710) and a wireless charging coil (720), the wireless charging coil (720) being connected to the battery (710), the battery (710) being used to supply power to the circuit board (600), the first hydrophone (200) and the second hydrophone (300).

5. The pipe inner wall scaling detector according to claim 4, characterized in that, The circuit board (600) is also provided with a power supply voltage regulator module, which is connected to the battery (710).

6. The pipe inner wall scaling detector according to claim 4, characterized in that, The spherical shell (100) includes an upper shell (110) and a lower shell (120). The second hydrophone (300) and the circuit board (600) are mounted on the upper shell (110), and the battery (710) and the wireless charging coil (720) are mounted on the lower shell (120).

7. The pipe inner wall scaling detector according to claim 1, characterized in that, The circuit board (600) is also equipped with an MCU, an onboard flash storage module and a wireless transmission module; The MCU is connected to the first hydrophone (200), the second hydrophone (300), the accelerometer, the onboard flash memory module, and the wireless transmission module.

8. The pipe inner wall scaling detector according to claim 1, characterized in that, The shock absorber ring (500) is an O-ring.

9. A pipe inner wall scaling detection system, characterized in that, The device includes the pipe inner wall scaling detector as described in claim 1, and further includes an external magnetic field, wherein multiple external magnetic fields are spaced apart along the length of the pipe.

10. A method for detecting scale buildup on the inner wall of a pipe, using a pipe scale detector as described in any one of claims 1-8, characterized in that, Includes the following steps: Signal acquisition: The scale detector on the inner wall of the pipe is placed in the pipe and rolled along the pipe under the action of water flow. The first hydrophone (200) and the second hydrophone (300) collect sound signals, and the accelerometer collects acceleration signals. Data analysis: The acceleration signal of the pipe inner wall scaling detector is a sinusoidal signal, and the frequency of the sinusoidal signal in the scaling section is greater than that in the non-scaling section; at the same time, the pipe inner wall scaling detector generates noise signals when entering and exiting the scaling section, which are used to determine whether there is scaling and diameter change; when the surface of the scaling section is uneven, the amplitude of the acceleration signal in the scaling section is greater than that in the non-scaling section or the integrity of the acceleration signal waveform is destroyed, showing a non-sinusoidal shape.

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