A self-propelled pipeline flaw detection device and method

Abstract

This invention discloses a self-propelled pipeline flaw detection device and method, relating to the field of pipeline maintenance technology. It includes a frame, a drive mechanism for self-propelled movement, and an information acquisition device for collecting information about the pipeline's internal structure. The frame is a rigid-flexible, segmentally adjustable connecting pipe. A bending drive mechanism is also provided, installed in the middle of the connecting pipe, for partially bending the connecting pipe to achieve steering of the pipeline flaw detection device. A drive mechanism is located on the connecting pipe, one in front of and one behind the bending drive mechanism. The information acquisition device is installed at the front end of the connecting pipe. This invention significantly improves the operational adaptability of the detection device in complex pipeline networks and increases flaw detection efficiency. It is particularly suitable for pipeline flaw detection operations in long-distance, multi-node complex pipeline networks, exhibiting strong adaptability to operating conditions, a simple and compact structure, and suitability for various working conditions.

Description

Technical Field

[0001] This invention relates to the field of pipeline maintenance technology, and more specifically to a device for internal flaw detection in complex pipeline networks. Background Technology

[0002] Pipelines are common industrial facilities that require regular internal inspection and maintenance. For pipelines with large diameters, high strength, short access distances, and low entry risks, internal inspection and maintenance are performed by personnel entering the pipeline facility, but this work inevitably carries a certain degree of danger. For pipelines with small diameters, long access distances, or high entry risks, pipeline inspection robots are used for internal inspection and maintenance.

[0003] In existing technologies, pipeline inspection robots are equipped with information acquisition devices to collect information, including images, about the inside of the pipeline for flaw detection. However, existing pipeline inspection robots are large and unsuitable for small pipelines or complex pipeline networks. Pipeline inspection robots with flexible connections between the pipeline and the information acquisition device often struggle to cross large-diameter "+" or "T" shaped pipeline nodes; while those with rigid connections cannot adapt to curved or bend-shaped pipeline structures. Currently, these problems are overcome by dividing the pipeline into segments and conducting segmented flaw detection, which is time-consuming, labor-intensive, and inefficient. Furthermore, existing pipeline inspection robots are particularly inadequate for detecting flaws inside pipelines with upward bends, which require manual entry for inspection. Summary of the Invention

[0004] To avoid the shortcomings of the prior art, the present invention provides a self-propelled pipeline flaw detection device and method.

[0005] To solve the technical problem, this invention adopts the following technical solution: a self-propelled pipeline flaw detection device, comprising a frame, a drive mechanism for driving itself forward, and an information acquisition device for collecting information about the inside of the pipeline. The frame is a rigid-flexible, segmentally adjustable connecting pipe. It is also provided with a bending drive mechanism, which is installed in the middle of the connecting pipe. A drive mechanism is provided on the connecting pipe in front of and behind the bending drive mechanism. The information collection device is installed at the front end of the connecting pipe. The bending drive mechanism includes a rotating ring, a connecting block, a clamping wheel, and a telescopic rod; The number of connecting blocks is at least two. Each of the connecting blocks is sequentially sleeved onto the connecting tube. At least one of the connecting blocks located at the front end or the rear end has a rotating ring connected to the connecting tube in front of or behind it. The rotating ring has a built-in rotating drive motor for driving the connecting block to rotate around the connecting tube. Each of the connecting blocks is hinged to the adjacent connecting block on the same side of the connecting pipe; a clamping wheel with its rim pressed against the outside of the connecting pipe is rotatably mounted on each of the connecting blocks on both sides of the connecting pipe, and a telescopic rod is provided between two adjacent connecting blocks in an offset manner; the two ends of the telescopic rod are rotatably mounted to the clamping wheels on the two adjacent connecting blocks on both sides of the connecting pipe, and the offset direction of each telescopic rod is the same; the telescopic rod has a built-in linear drive motor for driving its own extension or retraction.

[0006] Furthermore, the connecting pipe includes a flexible outer tube, an inner tube, and a magnetic field generating device, or the connecting pipe includes a flexible outer tube, an inner tube, and an electric field generating device; The outer tube is fitted over the inner tube, and the interlayer cavity formed between them is divided into multiple non-communicating small chambers by diaphragms arranged in the interlayer; the small chambers are filled with magnetorheological fluid or electrorheological fluid.

[0007] Furthermore, the driving mechanism includes a fixed water bag, a driving water bag, a movable water bag, a return spring, and a water injection device; The fixed water bag, the return spring, and the movable water bag are sequentially sleeved onto the outside of the connecting pipe from front to back. The fixed water bag is fixedly installed to the connecting pipe, and the movable water bag is slidably connected to the connecting pipe through a sealing slip ring, forming a sliding pair along the axial direction of the connecting pipe. The driving water bag is located between the fixed water bag and the movable water bag, and both ends of the driving water bag and the return spring are respectively connected and fixed to the fixed water bag and the movable water bag. The fixed water bag, the driving water bag, and the movable water bag are all connected to a water pumping or injecting device for pumping water from or into them. The fixed water bag and the movable water bag contract or expand radially along the connecting pipe when pumping water and injecting water, respectively, and the driving water bag contracts or expands axially along the connecting pipe when pumping water and injecting water.

[0008] Furthermore, the driving water bag has an axisymmetric structure about the axis of the connecting pipe or the driving water bag is arranged axisymmetrically about the axis of the connecting pipe.

[0009] Furthermore, the fixed water bag and the movable water bag are in the shape of annular bags, and the driving water bag is in the shape of a long strip bag, arranged in pairs symmetrically on both sides of the connecting pipe.

[0010] Furthermore, it also includes an adjustment mechanism for adjusting the acquisition angle of the information acquisition device.

[0011] Furthermore, the adjustment mechanism is an annular water bag; The information collection device is located at the center of the annular structure and is fixedly installed with the regulating water bag; the inner cavity of the regulating water bag is divided into small, non-communicating cavities by circumferentially arranged partitions, and each small cavity is independently connected to a water pumping or injecting device that pumps water from or injects water into it.

[0012] Furthermore, the telescopic rod is a hydraulic cylinder or a pneumatic cylinder, and the information acquisition device is a camera.

[0013] A self-injecting pipeline flaw detection method, using the aforementioned self-injecting pipeline flaw detection device to perform flaw detection inside the pipeline, includes the following process: Adjust the installation position of the drive mechanism on the connecting pipe according to the pipe diameter and shape. After adjustment, fix the water bag of the drive mechanism to the connecting pipe. The pipeline flaw detection device is placed inside the pipeline, and its operating mode is adjusted based on the information collected and fed back by the information acquisition device. If the environment inside the pipeline requires the pipeline flaw detection device to travel straight, the pipeline flaw detection device will enter straight-travel mode. If the environment inside the pipeline requires the pipeline flaw detection device to turn, the pipeline flaw detection device will enter the turning mode. If there are obstacles in the environment ahead of the pipeline, the pipeline flaw detection device will enter obstacle-crossing mode. Straight-through mode: The first step is to activate the magnetic field generator or electric field generator so that the part of the connecting tube corresponding to the drive mechanism position is expressed as a rigid structure. The second step is to inject water into the movable water bag using the water injection device, so that the movable water bag extends radially along the connecting pipe until it is pressed against the inner wall of the pipe and fixed. The water injection device injects water into the driving water bag, causing the driving water bag to extend along the axial direction of the connecting pipe, pushing the fixed water bag and the connecting pipe fixedly installed with the fixed water bag to move forward relative to the movable water bag. The driving mechanism and information acquisition device installed on the connecting pipe move forward with the connecting pipe. During this process, the return spring is stretched; The third step is to inject water into the fixed water bag using the water injection device, so that the fixed water bag extends radially along the connecting pipe until it is pressed against the inner wall of the pipe and fixed. The water pumping device draws water from the movable water bag and the driving water bag, causing the movable water bag to contract radially along the connecting pipe and separate from the inner wall of the pipe, and the driving water bag to shorten axially along the connecting pipe. Subsequently, the movable water bag compresses the driving water bag under the elastic force of the return spring and slides forward along the connecting pipe. Fourth, repeat steps two and three until the information collected by the information acquisition device indicates a change in the environmental type in front of the pipeline flaw detection device. Then, re-evaluate and adjust the working mode of the pipeline flaw detection device. Steering mode: In the first step, the pipeline flaw detection device advances in straight-line mode until the drive mechanism located at the rear reaches the turning position, and the movable water bag in the drive mechanism located at the rear is filled with water until it is pressed against the inner wall of the pipeline and fixed, while the drive mechanism located at the front remains separated from the inner wall of the pipeline. The second step is to change the operating parameters of the electric field generating device or the magnetic field generating device so that the connecting pipe at the corresponding position of the bending drive mechanism is expressed as a flexible structure, and the other positions are expressed as a rigid structure. Third, the rotating ring drives the bending drive mechanism to rotate around the connecting pipe according to the steering requirements until the hinged side of each connecting block is located inside the steering trajectory. Then, each telescopic rod extends, causing the connecting pipe, which is a flexible structure, to bend into an arc shape that adapts to the steering trajectory. Fourth, the drive mechanism located on the rear side works in straight-line mode until the drive mechanism located on the front side contacts the pipe inner wall located on the far side after the steering. At this time, in the drive mechanism located on the front side, the movable water bag is filled with water until it is pressed against the inner wall of the pipe and fixed. The drive mechanism located on the rear side pumps water until it is separated from the inner wall of the pipe. Fifth, the drive mechanism located on the front side operates in straight-line mode until the pipeline flaw detection device completes its turn. At this time, the drive mechanism located on the rear side also enters the pipeline area after the turn.

[0014] Subsequently, based on the information collected and fed back by the information acquisition device, the working mode of the pipeline flaw detection device was reassessed and adjusted. Furthermore, the acquisition position and angle of the information acquisition device are adjusted as follows: The water injection or extraction device independently injects or pumps water into each small cavity, adjusts the shape of each small cavity, and causes the information acquisition device to shift and flip to one side.

[0015] This invention provides a self-propelled pipeline flaw detection device and method, which has the following beneficial effects: This invention can greatly improve the adaptability of the detection device in complex pipeline networks and improve the efficiency of flaw detection. It is particularly suitable for pipeline flaw detection operations in complex pipeline networks with long distances and multiple nodes. It has strong adaptability to operating conditions, simple and compact structure, and is suitable for various working conditions. At the same time, this invention is mainly driven by hydraulic and water power, which is especially suitable for pipelines that may contain dangerous gases, and has high working safety. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the front cross-sectional structure of the present invention; Figure 2 This is a partially enlarged cross-sectional view of the connecting pipe of the present invention; Figure 3 This is a right-side cross-sectional view of the adjustment mechanism of the information acquisition device of the present invention when it is centered. Figure 4 This is a right-side cross-sectional view of the information acquisition device bias adjustment mechanism of the present invention. Figure 5 This is a schematic diagram of the state before the present invention changes direction; Figure 6 This is a schematic diagram of the first state during the turning process of the present invention; Figure 7 This is a schematic diagram of the second state during the turning process of the present invention; Figure 8 This is a schematic diagram of the state after the present invention has been turned.

[0017] In the picture: 1. Connecting pipe; 11. Outer pipe; 12. Inner pipe; 13. Diaphragm; 14. Chamber; 2. Information acquisition device; 3. Drive mechanism; 31. Fixed water bag; 32. Drive water bag; 33. Movable water bag; 34. Return spring; 4. Bending drive mechanism; 41. Rotating ring; 42. Connecting block; 43. Clamping wheel; 44. Telescopic rod; 5. Adjustment mechanism; 51. Partition; 52. Chamber. Detailed Implementation

[0018] 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 in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] A self-propelled pipe flaw detection device, such as Figures 1-2As shown, its structural relationship is as follows: it includes a frame, a drive mechanism 3 for driving itself forward, and an information acquisition device 2 for collecting information inside the pipeline. The frame is a rigid and flexible segmented adjustable connecting pipe 1. In actual installation, the wires and signal lines used for controlling or powering the pipeline flaw detection device can be arranged inside the connecting pipe 1. It is also equipped with a bending drive mechanism 4, which is installed in the middle of the connecting pipe 1. A drive mechanism 3 is provided in front of and behind the bending drive mechanism 4 on the connecting pipe 1. The information acquisition device 2 is installed at the front end of the connecting pipe 1. The bending drive mechanism 4 includes a rotating ring 41, a connecting block 42, a clamping wheel 43, and a telescopic rod 44; The number of connecting blocks 42 is at least two, and in actual installation, the number of connecting blocks 42 can preferably be five; each connecting block 42 is sequentially sleeved onto the connecting pipe 1, and at least one of the connecting blocks 42 located at the front end or the rear end has a rotating ring 41 sleeved onto the connecting pipe 1 connected in front of or behind it, and the rotating ring 41 has a built-in rotating drive motor for driving the connecting block 42 to rotate around the connecting pipe 1. Each connecting block 42 is hinged to the adjacent connecting block 42 on the same side of the connecting pipe 1; a clamping wheel 43 with its rim pressed against the outside of the connecting pipe 1 is rotatably mounted on each of the connecting blocks 42 on both sides of the connecting pipe 1, and a telescopic rod 44 is provided between two adjacent connecting blocks 42 in an offset manner and installed and connected to both of them; the two ends of the telescopic rod 44 are rotatably installed and connected to the clamping wheels 43 on the two adjacent connecting blocks 42 on both sides of the connecting pipe 1, and the offset direction of each telescopic rod 44 is the same; the telescopic rod 44 has a built-in linear drive motor for driving itself to extend or shorten.

[0020] Preferably, the connecting tube 1 includes a flexible outer tube 11, an inner tube 12, and a magnetic field generating device, or the connecting tube 1 includes a flexible outer tube 11, an inner tube 12, and an electric field generating device. The outer tube 11 is fitted outside the inner tube 12, and the interlayer cavity formed between the two is divided into multiple non-communicating small chambers 14 by diaphragms arranged in the interlayer; the small chambers are filled with magnetorheological fluid or electrorheological fluid.

[0021] Magnetorheological fluids or electrorheological fluids can change their rigidity and flexibility under the action of an external magnetic field or an external electric field. The rigidity and flexibility of the magnetorheological fluids or electrorheological fluids in different chambers 14 can be independently adjusted to support the segmented adjustment of the rigidity and flexibility of the connecting tube 1.

[0022] Preferably, the drive mechanism 3 includes a fixed water bag 31, a drive water bag 32, a movable water bag 33, a return spring 34, and a water injection device; The fixed water bag 31, the return spring 34, and the movable water bag 33 are sequentially fitted onto the outside of the connecting pipe 1 from front to back. The fixed water bag 31 is fixedly installed to the connecting pipe 1, and the movable water bag 33 is slidably connected to the connecting pipe 1 through a sealing slip ring, forming a sliding pair along the axial direction of the connecting pipe 1. The driving water bag 32 is located between the fixed water bag 31 and the movable water bag 33, and both ends of the driving water bag 32 and the return spring 34 are respectively connected and fixed to the fixed water bag 31 and the movable water bag 33. The fixed water bag 31, the driving water bag 32, and the movable water bag 33 are all connected to a water pumping or injecting device for pumping water from or into them. The fixed water bag 31 and the movable water bag 33 contract or expand radially along the connecting pipe when pumping water and injecting water, respectively, while the driving water bag 32 contracts or expands axially along the connecting pipe 1 when pumping water and injecting water.

[0023] Preferably, the driving water bag 32 has an axisymmetric structure about the axis of the connecting pipe 1 or the driving water bag 32 is arranged axisymmetrically about the axis of the connecting pipe.

[0024] Preferably, the fixed water bag 31 and the movable water bag 33 are in the shape of annular bags, and the driving water bag 32 is in the shape of a long strip bag, and are arranged symmetrically in pairs on both sides of the connecting pipe 1.

[0025] Preferably, it also includes an adjustment mechanism 5 for adjusting the acquisition angle of the information acquisition device 2.

[0026] Preferably, the adjusting mechanism 5 is an adjusting water bag with a ring structure; The information acquisition device 2 is located at the center of the ring structure and is fixedly installed with the regulating water bag. The inner cavity of the regulating water bag is divided into small cavities 52 that are not connected to each other by the circumferentially arranged partitions 51. Each small cavity 52 is independently connected to a water pumping or injecting device that pumps water from or injects water into it.

[0027] Preferably, the telescopic rod 44 is a hydraulic cylinder or a pneumatic cylinder, and the information acquisition device 2 is a camera.

[0028] The method for performing internal pipe flaw detection using the above-mentioned self-entering pipe flaw detection device includes the following steps: According to the pipe diameter and shape, adjust the installation position of the drive mechanism 3 on the connecting pipe 1. After adjustment, fix the fixed water bag 31 of the drive mechanism 3 to the connecting pipe 1. The pipeline flaw detection device is placed inside the pipeline, and the working mode of the pipeline flaw detection device is adjusted according to the information collected and fed back by the information acquisition device 2. If the environment inside the pipeline requires the pipeline flaw detection device to travel straight, the pipeline flaw detection device will enter straight-travel mode. If the environment inside the pipeline requires the pipeline flaw detection device to turn, the pipeline flaw detection device will enter the turning mode. If there are obstacles in the environment ahead of the pipeline, the pipeline flaw detection device will enter obstacle-crossing mode. Straight-through mode: The first step is to activate the magnetic field generator or electric field generator so that the part of the connecting pipe 1 corresponding to the position of the driving mechanism 3 is expressed as a rigid structure. The second step is to inject water into the movable water bag 33 by the water injection device, so that the movable water bag 33 extends radially along the connecting pipe 1 and is fixed against the inner wall of the pipe. The water injection device injects water into the driving water bag 32, causing the driving water bag 32 to extend along the axial direction of the connecting pipe 1, pushing the fixed water bag 31 and the connecting pipe 1 fixedly installed with the fixed water bag 31 to move forward relative to the movable water bag 33. The driving mechanism 3 and the information acquisition device 2 installed on the connecting pipe 1 move forward with the connecting pipe 1. During this process, the return spring 34 is stretched; The third step is to inject water into the fixed water bag 31 by the water injection device, so that the fixed water bag 31 extends radially along the connecting pipe 1 and is fixed against the inner wall of the pipe. The water pumping device draws water from the movable water bag 33 and the driving water bag 32, causing the movable water bag to contract radially along the connecting pipe 1 and separate from the inner wall of the pipe. The driving water bag 32 shortens axially along the connecting pipe 1. Then, under the elastic force of the return spring 34, the movable water bag 33 compresses the driving water bag 32 and slides forward along the connecting pipe 1. Fourth, repeat steps two and three until the information collected by the information acquisition device 2 indicates a change in the environmental type in front of the pipeline flaw detection device inside the pipeline, and re-evaluate and adjust the working mode of the pipeline flaw detection device. In straight-line mode, the pipe flaw detection device can be driven straight-line by only one of the two drive devices 3, or the two drive devices can be controlled to move synchronously and work together to drive the pipe flaw detection device straight-line. Steering mode: In the first step, the pipeline flaw detection device advances in straight-line mode until the drive mechanism 3 located at the rear reaches the turning position, and the movable water bag 33 in the drive mechanism 3 located at the rear is filled with water until it is pressed against the inner wall of the pipeline and fixed, while the drive mechanism 3 located at the front remains separated from the inner wall of the pipeline. The second step is to change the operating parameters of the electric field generating device or the magnetic field generating device so that the connecting pipe 1 at the corresponding position of the bending drive mechanism 4 is expressed as a flexible structure, and the other positions are expressed as a rigid structure. Third, the rotating ring 41 drives the bending drive mechanism 4 to rotate around the connecting pipe 1 according to the steering requirements, until the hinged side of each connecting block 42 is located inside the steering trajectory. Then, each telescopic rod 44 extends, so that the connecting pipe 1, which is a flexible structure expressed by the bending drive mechanism 4, deforms and bends into an arc shape that adapts to the steering trajectory. Fourth, the drive mechanism 3 located on the rear side works in straight mode until the drive mechanism 3 located on the front side contacts the pipe inner wall located on the far side in the pipe area after the steering. At this time, in the drive mechanism 3 located on the front side, the movable water bag 33 is filled with water until it is pressed against the inner wall of the pipe and fixed. The drive mechanism 3 located on the rear side pumps water until it is separated from the inner wall of the pipe. Fifth, the drive mechanism 3 located on the front side operates in straight-line mode until the pipeline flaw detection device completes its turn. At this time, the drive mechanism 3 located on the rear side also enters the pipeline area after the turn.

[0029] Subsequently, based on the information collected and fed back by the information acquisition device 2, the working mode of the pipeline flaw detection device was re-evaluated and adjusted. In steering mode, relying on the rotation drive of the rotating ring 41, the pipe flaw detection device can not only turn in the current plane of travel, but also flip and turn upwards or downwards, which has extremely high flexibility.

[0030] Preferably, the acquisition position and angle of the information acquisition device 2 are adjusted as follows: The water injection or pumping device independently injects or pumps water into each small cavity 52, adjusts the shape of each small cavity 52, and drives the information acquisition device 2 to shift and flip to one side.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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 of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-propelled pipeline flaw detection device, comprising a frame, a drive mechanism (3) for driving itself forward, and an information acquisition device (2) for acquiring information about the inside of the pipeline, characterized in that: The frame is a rigid-flexible, segmented, adjustable connecting pipe (1). A bending drive mechanism (4) is also provided. The bending drive mechanism (4) is installed in the middle of the connecting pipe (1). A drive mechanism (3) is provided in front of and behind the bending drive mechanism (4) on the connecting pipe (1). The information acquisition device (2) is installed at the front end of the connecting pipe (1). The bending drive mechanism (4) includes a rotating ring (41), a connecting block (42), a clamping wheel (43), and a telescopic rod (44). The number of the connecting blocks (42) is at least two. Each of the connecting blocks (42) is sequentially sleeved onto the connecting pipe (1). At least one of the connecting blocks (42) located at the front end or the rear end has a rotating ring (41) sleeved onto the connecting pipe (1) connected in front of or behind it. The rotating ring (41) has a built-in rotating drive motor for driving the connecting block (42) to rotate around the connecting pipe (1). Each of the connecting blocks (42) is hinged to the adjacent connecting block (42) on the same side of the connecting pipe (1); each of the connecting blocks (42) has a clamping wheel (43) with its rim pressed against the outside of the connecting pipe (1) on each side of the connecting pipe (1), and a telescopic rod (44) is provided between two adjacent connecting blocks (42) in an offset manner and installed and connected to both of them; the two ends of the telescopic rod (44) are respectively rotatably installed and connected to the clamping wheels (43) on the two adjacent connecting blocks (42) on both sides of the connecting pipe (1), and the offset direction of each telescopic rod (44) is the same; the telescopic rod (44) has a built-in linear drive motor for driving itself to extend or shorten; The connecting tube (1) includes a soft outer tube (11), an inner tube (12) and a magnetic field generating device, or the connecting tube (1) includes a soft outer tube (11), an inner tube (12) and an electric field generating device; The outer tube (11) is fitted over the inner tube (12), and the interlayer cavity formed between them is divided into multiple non-communicating small chambers (14) by a diaphragm arranged in the interlayer; the small chambers are filled with magnetorheological fluid or electrorheological fluid.

2. The self-propelled pipeline flaw detection device according to claim 1, characterized in that: The drive mechanism (3) includes a fixed water bag (31), a drive water bag (32), a movable water bag (33), a return spring (34), and a water injection device; The fixed water bag (31), the return spring (34), and the movable water bag (33) are sequentially sleeved onto the outside of the connecting pipe (1) from front to back. The fixed water bag (31) is fixedly installed to the connecting pipe (1), and the movable water bag (33) is slidably connected to the connecting pipe (1) through a sealing slip ring, forming a sliding pair along the axial direction of the connecting pipe (1). The driving water bag (32) is located between the fixed water bag (31) and the movable water bag (33), and both ends of the driving water bag (32) and the return spring (34) are respectively connected and fixed to the fixed water bag (31) and the movable water bag (33). The fixed water bag (31), the driving water bag (32), and the movable water bag (33) are all connected to a water pumping or injecting device for pumping water from or injecting water into them. The fixed water bag (31) and the movable water bag (33) contract or expand radially along the connecting pipe when pumping water and injecting water, respectively. The driving water bag (32) contracts or expands axially along the connecting pipe (1) when pumping water and injecting water.

3. The self-propelled pipeline flaw detection device according to claim 2, characterized in that: The driving water bag (32) is axially symmetric about the axis of the connecting pipe (1) or the driving water bag (32) is axially symmetric about the axis of the connecting pipe.

4. The self-propelled pipeline flaw detection device according to claim 3, characterized in that: The fixed water bag (31) and the movable water bag (33) are in the shape of annular bags, and the driving water bag (32) is in the shape of a long strip bag, and are arranged symmetrically in pairs on both sides of the connecting pipe (1).

5. A self-propelled pipeline flaw detection device according to claim 2, characterized in that: It also includes an adjustment mechanism (5) for adjusting the acquisition angle of the information acquisition device (2).

6. The self-propelled pipeline flaw detection device according to claim 5, characterized in that: The adjustment mechanism (5) is an annular water bag; The information collection device (2) is located at the center of the ring structure and is fixed to the regulating water bag; the inner cavity of the regulating water bag is divided into small cavities (52) that are not connected to each other by the circumferentially arranged partitions (51), and each small cavity (52) is independently connected to a water pumping device that pumps water from or injects water into it.

7. A self-propelled pipeline flaw detection device according to claim 2, characterized in that: The telescopic rod (44) is a hydraulic cylinder or a pneumatic cylinder, and the information acquisition device (2) is a camera.

8. A self-propelled pipe flaw detection method, using the self-propelled pipe flaw detection device as described in any one of claims 2-4 or claim 7 to perform flaw detection inside the pipe, characterized in that, The process includes the following: According to the pipe diameter and shape, adjust the installation position of the drive mechanism (3) on the connecting pipe (1). After adjustment, fix the water bag (31) of the drive mechanism (3) to the connecting pipe (1). The pipeline flaw detection device is placed inside the pipeline, and the working mode of the pipeline flaw detection device is adjusted according to the information collected and fed back by the information acquisition device (2): If the environment inside the pipeline requires the pipeline flaw detection device to travel straight, the pipeline flaw detection device will enter straight-travel mode. If the environment inside the pipeline requires the pipeline flaw detection device to turn, the pipeline flaw detection device will enter the turning mode. If there are obstacles in the environment ahead of the pipeline, the pipeline flaw detection device will enter obstacle-crossing mode. Straight-through mode: The first step is to operate the magnetic field generating device or the electric field generating device so that the part of the connecting pipe (1) corresponding to the position of the driving mechanism (3) is expressed as a rigid structure; The second step is to inject water into the movable water bag (33) using the water injection device, so that the movable water bag (33) extends radially along the connecting pipe (1) until it is pressed against the inner wall of the pipe and fixed. The water injection device injects water into the driving water bag (32), causing the driving water bag (32) to extend along the axial direction of the connecting pipe (1), pushing the fixed water bag (31) and the connecting pipe (1) fixedly installed with the fixed water bag (31) to move forward relative to the movable water bag (33). The driving mechanism (3) and the information acquisition device (2) installed on the connecting pipe (1) move forward along with the connecting pipe (1). During this process, the return spring (34) is stretched; The third step is to inject water into the fixed water bag (31) using the water injection device, so that the fixed water bag (31) extends radially along the connecting pipe (1) and is fixed against the inner wall of the pipe. The water pumping device draws water from the movable water bag (33) and the driving water bag (32), causing the movable water bag to contract radially along the connecting pipe (1) and separate from the inner wall of the pipe. The driving water bag (32) shortens axially along the connecting pipe (1). Subsequently, the movable water bag (33) compresses the driving water bag (32) under the elastic force of the return spring (34) and slides forward along the connecting pipe (1). Fourth step, repeat the second and third steps until the information collection device (2) collects and feedback information indicating that the environment type in front of the pipeline flaw detection device has changed, and re-judge and adjust the working mode of the pipeline flaw detection device. Steering mode: In the first step, the pipeline flaw detection device advances to the drive mechanism (3) located on the rear side in the straight-line working mode and reaches the turning position. Water is injected into the movable water bag (33) in the drive mechanism (3) located on the rear side until it is pressed against the inner wall of the pipeline and fixed. The drive mechanism (3) located on the front side remains separated from the inner wall of the pipeline. The second step is to change the working parameters of the electric field generating device or the magnetic field generating device so that the connecting pipe (1) at the corresponding position of the bending drive mechanism (4) is expressed as a flexible structure, and the other positions are expressed as a rigid structure. Third step, the rotating ring (41) drives the bending drive mechanism (4) to rotate around the connecting pipe (1) according to the steering requirements, until the hinged side of each connecting block (42) is located inside the steering trajectory. Then each telescopic rod (44) extends, so that the connecting pipe (1) with the corresponding position of the bending drive mechanism (4) is deformed and bent into an arc shape that adapts to the steering trajectory. Fourth step, the drive mechanism (3) located on the rear side works in straight mode until the drive mechanism (3) located on the front side contacts the pipe inner wall located on the far side in the pipe area after the steering. At this time, in the drive mechanism (3) located on the front side, the movable water bag (33) is filled with water until it is pressed against the inner wall of the pipe and fixed. The drive mechanism (3) located on the rear side pumps water until it is separated from the inner wall of the pipe. Fifth step, the drive mechanism (3) located on the front side works in straight mode until the pipeline flaw detection device completes the turn. At this time, the drive mechanism (3) located on the rear side also enters the pipeline area after the turn. Subsequently, based on the information collected and fed back by the information acquisition device (2), the working mode of the pipeline flaw detection device is re-evaluated and adjusted.

9. A self-propelled pipeline flaw detection method according to claim 8, characterized in that: The self-entering pipeline flaw detection device used in the self-entering pipeline flaw detection method also includes an adjustment mechanism (5) for adjusting the acquisition angle of the information acquisition device (2); the adjustment mechanism (5) is an annular structure adjustment water bag, the information acquisition device (2) is located at the center of the annular structure and is fixedly installed with the adjustment water bag; the inner cavity of the adjustment water bag is divided into non-communicating small cavities (52) by circumferentially arranged partitions (51), and each small cavity (52) is independently connected to a water pumping or injecting device that pumps water from or injects water into it; In the self-propelled pipeline flaw detection method, the acquisition position and angle of the information acquisition device (2) are adjusted as follows: The water injection or pumping device independently injects or pumps water into each small cavity (52), adjusts the shape of each small cavity (52), and drives the information acquisition device (2) to shift and flip to one side.

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