A motion device for detecting the inner surface of a pressurized pipeline

Abstract

The present invention discloses a moving device for detecting the inner surface of a pressurized pipeline. The device comprises a forward power support and a lateral power support. Three front buoyancy blocks and three groups of power wheel modules are respectively installed in front of the forward power support, and a front cover is installed at the end. A forward power module is installed inside the forward power support. The lateral power support is connected to the rear end of the forward power support, and three rear buoyancy blocks and three groups of power wheel modules are provided at the other end of the lateral power support. A lateral power module is arranged between the lateral power support and the filter screen, and the installation direction of the lateral power module is consistent with the installation direction of one of the groups of power wheel modules. The present invention realizes the stable circumferential movement along the pipe wall without using complex devices such as electric slip rings and servos through simple mechanism design, providing a new idea for the detection task of the pressurized pipeline wall.

Description

Technical Field

[0001] The present invention relates to the field of pressure pipeline detection, and particularly to a motion device for detecting the inner surface of a pressure pipeline. Background Art

[0002] The in-pipe inspection technology for pressure pipelines is a detection method that has developed rapidly in recent years. It mainly uses pipeline fluid as power and can achieve observing the internal environment of the pipe and listening for leakage sounds inside the pipe. Currently, pressure pipeline detection equipment is increasingly applied to the leakage detection tasks of urban water supply pipelines. This detection method can provide a more intuitive view of the internal environment of the pipe and accurately detect the leakage location compared to traditional correlation methods, listening rods and other detection methods.

[0003] However, with the continuous growth of in-pipe inspection requirements, there have emerged many requirements such as in-pipe inspection in large tunnels, in-pipe inspection in raw water pipelines, and in-pipe inspection of the corrosion condition of the pipe wall. Currently, due to the presence of large tunnels or unclear inner walls in turbid pipelines such as raw water pipelines, the detection effect of pipeline detection equipment is greatly affected. On the other hand, tasks such as observing the corrosion condition of the pipe wall and detecting pipeline welds require the equipment to operate stably. The existing technology cannot make the detection equipment and the sensors on it operate stably. Even with power mechanisms such as propellers, it is difficult to maintain a stable state in the turbulent pipeline fluid environment.

[0004] On the other hand, it is also a difficult problem to place equipment inside a pressure pipeline in an operating state. The main external interfaces of water supply pipelines are valves with a diameter of DN100. In order to place equipment inside a pressure pipeline, the current pressure pipeline detection equipment on the market is mainly in the shape of a cylindrical cylinder, and the diameter is less than 100MM, which further limits the use of the existing technology for the detection task of the inner surface of the pipeline. Summary of the Invention

[0005] The present invention provides a motion device for detecting the inner surface of a pressure pipeline. The present invention realizes the stable circumferential movement along the pipe wall of the equipment without using complex devices such as electrical slip rings and servos through a simple mechanism design, providing a new idea for the detection task of the pressure pipeline wall. See the following description for details:

[0006] A motion device for detecting the inner surface of a pressure pipeline, the device comprising: a forward power support and a lateral power support,

[0007] Three front buoyancy blocks and three groups of power wheel modules are respectively installed in front of the forward power support, and a front cover is installed at the end. A forward power module is installed inside the forward power support. The lateral power support is connected to the rear end of the forward power support, and three rear buoyancy blocks and three groups of power wheel modules are provided at the other end of the lateral power support;

[0008] A lateral power module is provided between the lateral power support and the filter screen, and the installation direction of the lateral power module is consistent with the installation direction of one set of power wheel modules.

[0009] Among them, three front power wheel brackets are symmetrically distributed on the forward power support, and the geometric centers of the three front power wheel brackets coincide with the center of the forward power support.

[0010] Further, the front power wheel bracket is provided with a first movable groove, a first limiting groove, a first shaft hole and a front cover seat.

[0011] The first movable groove is located in the middle of the front power wheel bracket and is used to pass through the power wheel module. First shaft holes are provided on both sides of the first movable groove for supporting the power wheel module, and a first limiting groove is provided at the bottom of the first movable groove for limiting the power wheel module.

[0012] Among them, the power wheel module includes: a wheel support.

[0013] One end of the wheel support is provided with a nut for fixing the wheel, and the nut is embedded inside the support. A symmetrically centered rotatable rotating shaft is provided in the middle of the wheel support for installation in the first shaft hole. Limiting inclined surfaces are symmetrically provided on both sides of the wheel support between the rotating shaft and the nut, and the included angle between the two inclined surfaces is exactly equal to the included angle of the first limiting groove on the forward power support. A cut-off surface is provided at the intersection of the limiting inclined surfaces.

[0014] The other end of the wheel support is provided with a spring fixing hole for installing one end of the spring, and the other end of the spring is installed on the cross beam of the front cover or the corresponding hook on the lateral power support.

[0015] Three rear power wheel brackets are symmetrically distributed on the lateral power support. One end of the three rear power wheel brackets is connected to the lateral thruster fixing seat, and a connecting bracket for connecting to the forward power support is provided on the other side. The lateral power module is installed in the middle of the lateral thruster fixing seat, and the power direction is perpendicular to the direction of the forward power module.

[0016] The rear power wheel bracket is provided with a second movable groove, a second limiting groove, a second shaft hole and a gland fixing seat. A hook is provided at the end of the rear power wheel bracket away from the second limiting groove for connecting with one end of the spring.

[0017] The device is also provided with a rear buoyancy block, which is installed in the middle of the three rear power wheel brackets.

[0018] Both the front and rear buoyancy blocks adopt a thin-walled hollow structure and are integrally formed by 3D printing with resin material, or formed by separate injection molding and then adhered together. The internal chamber of the integrally formed buoyancy block is filled with air.

[0019] The beneficial effects of the technical solution provided by the present invention are:

[0020] 1. The present invention adopts two simply vertically arranged power modules, achieving the mode of circular motion along the pipe wall circumference and the mode of being stationary while conforming to the pipe wall without using complex servos to assist the device.

[0021] 2. The power wheel modules designed in the present invention are distributed in an equilateral triangle, and their directions are organically combined with the power directions of the lateral power modules, achieving the randomness of the circular operation direction, ensuring that the probabilities of counterclockwise and clockwise movements are the same, without the need for other complex control logics, and further protecting the possible twisting damage of the cables at the end of the device, avoiding the use of complex connection mechanisms such as electrical slip rings.

[0022] 3. The present invention can use a simple spring to fold inward and bend or expand freely, so that the outer diameter size can be reduced during deployment. After the outer diameter is reduced, the device can pass through a DN100 or smaller gate valve on the pipeline, which brings great convenience to the deployment. After entering the pipeline, under the action of the spring, the power wheel modules automatically expand into the working mode without the need for other complex control modules.

[0023] 4. The power wheel modules designed in the present invention can only bend and close in the direction away from the cable. When recovering the device, the power wheel modules automatically close inward under the action of the narrow inner wall of the gate valve and other deployment ports, so that the entire device can be smoothly recovered without the need for other auxiliary power.

[0024] 5. The present invention has a simple structure and powerful functions, with great application value and potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is the external shape structure diagram of the in-pipe surface detection and movement device for a pressurized pipeline;

[0026] Figure 2 It is the schematic diagram of the installation of the lateral power module;

[0027] Figure 3 It is the structure diagram of the forward power support;

[0028] Figure 4 It is the structure diagram of the power wheel module;

[0029] Figure 5 It is the structure diagram of the front cover;

[0030] Figure 6 It is the structure diagram of the lateral power support;

[0031] Figure 7 It is the sectional view of the lateral power support;

[0032] Figure 8 It is the sectional view of the in-pipe surface detection and movement device for a pressurized pipeline;

[0033] Figure 9 Schematic diagram of the recovery of the driving wheel module;

[0034] Figure 10 Front view of the driving wheel module after recovery;

[0035] Figure 11 Structure diagram of the buoyancy block;

[0036] Figure 12 Position relationship diagram of the driving wheel module;

[0037] Figure 13 Schematic diagram of the movement mode of the in-pipe surface inspection device for pressurized pipelines on the ground;

[0038] Figure 14 Schematic diagram of the circumferential movement mode of the in-pipe surface inspection device for pressurized pipelines on the pipe wall;

[0039] Figure 15 Schematic diagram of the static fit of the in-pipe surface inspection device for pressurized pipelines on the pipe wall.

[0040] In the attached drawings, the list of components represented by each label is as follows:

[0041] 1: Forward power support; 2: Lateral power support;

[0042] 3: Front buoyancy block; 4: Rear buoyancy block;

[0043] 5: Driving wheel module; 6: Front cover;

[0044] 7: Gland; 8: Cable;

[0045] 9: Spring; 10: Forward power module;

[0046] 11: Lateral power module; 12: Filter screen;

[0047] 100: Front driving wheel support; 101: First movable groove;

[0048] 102: First limiting groove; 103: First shaft hole;

[0049] 104: Forward thruster fixing seat; 105: Front cover seat;

[0050] 106: Lateral support; 200: Rear driving wheel support;

[0051] 201: Second movable groove; 202: Second limiting groove;

[0052] 203: Second shaft hole; 204: Lateral thruster fixing seat;

[0053] 205: Gland fixing seat; 206: Connecting support;

[0054] 207: Hook; 500: Wheel support;

[0055] 501: Limit inclined plane; 502: Wheel;

[0056] 503: Bearing screw; 504: Nut;

[0057] 505: Rotating shaft; 506: Spring fixing hole;

[0058] 507: Cut-off surface. Detailed implementation mode

[0059] To make the objectives, technical solutions and advantages of the present invention clearer, the following further describes the implementation modes of the present invention in detail.

[0060] See Figures 1 to 15 , the technical solution adopted in the embodiment of the present invention is to use two vertically placed power modules, one providing forward power and the other providing lateral power to achieve forward and lateral movement. A foldable power wheel module is adopted, which realizes the functions of the device moving clockwise or counterclockwise along the pipe wall and staying stationary in contact with the pipe wall under the action of the lateral power module. The small-size delivery port can be realized through the folding mechanism of the power wheel module.

[0061] Such as Figure 1 , 2 , as shown in 8, the embodiment of the present invention provides a motion device for detecting the inner surface of a pressurized pipeline, including: forward power bracket 1, lateral power bracket 2, front buoyancy block 3, rear buoyancy block 4, power wheel module 5, front cover 6, gland 7, cable 8, spring 9, forward power module 10, lateral power module 11 and filter screen 12.

[0062] Three front buoyancy blocks 3 and three groups of power wheel modules 5 are respectively installed in front of the forward power bracket 1, and the front cover 6 is installed at the end. The forward power module 10 is installed inside the forward power bracket 1. The lateral power bracket 2 is connected to the rear end of the forward power bracket 1. The other end of the lateral power bracket 2 is provided with three rear buoyancy blocks 4, three groups of power wheel modules 5 and gland 7. The cable 8 passes through the middle of the gland 7 and is respectively connected to the input interfaces of the forward power module 10 and the lateral power module 11. The lateral power module 11 is located between the lateral power bracket 2 and the filter screen 12, as Figure 2 shown. In addition, the installation direction (power direction) of the lateral power module 11 is consistent with the installation direction of one group of power wheel modules 5.

[0063] The forward power support 1 is mainly used for support and connection. Its overall structure is cylindrical, and it is provided with a front power wheel support 100, a first movable groove 101, a first limiting groove 102, a first shaft hole 103, a forward thruster fixing seat 104, a front cover seat 105, and a lateral support 106 on it, as Figure 3 shown. The overall structure of the forward power support 1 can be integrally formed or machined, and the materials include but are not limited to nylon, aluminum alloy, carbon fiber, etc. The front power wheel support 100 is used to support the power wheel module 5. In this embodiment, six groups of power wheel modules 5 are adopted and are respectively installed at the front and rear ends of the whole device. There are just three symmetrically distributed front power wheel supports 100 on the forward power support 1. The geometric centers of the three front power wheel supports 100 coincide with the center of the forward power support 1. A forward thruster fixing seat 104 is provided at the bottom of the three front power wheel supports 100. The forward thruster fixing seat 104 is used to fixedly install the forward power module 10, and the forward power module 10 can adopt a standard underwater thruster. The front power wheel support 100 is provided with a first movable groove 101, a first limiting groove 102, a first shaft hole 103, and a front cover seat 105. The first movable groove 101 is located in the middle of the front power wheel support 100 and is used to pass through the power wheel module 5. First shaft holes 103 are provided on both sides of the first movable groove 101 and are used to support the power wheel module 5. A first limiting groove 102 is provided at the bottom of the first movable groove 101 and is used to limit the power wheel module 5. The front cover seat 105 is used to install the front cover 6. The lateral support 106 at the other end of the forward power support 1 is mainly used to connect with the lateral power support 2 in the second half of the device to form the overall framework of the device.

[0064] The structure of the power wheel module 5 is as Figure 4As shown in the figure, its main function is to provide support and directional rotation when the device moves in contact with the inner wall of the pipeline, so as to ensure that the entire device moves along the circumferential circle of the pipeline. The power wheel module 5 includes: a wheel support 500, a limiting inclined plane 501, a wheel 502, a bearing screw 503, a nut 504, a rotating shaft 505, a spring fixing hole 506, and a cut-off surface 507. One end of the wheel support 500 is provided with a nut 504 for fixing the wheel 502. The nut 504 is embedded inside the bracket to prevent loosening. The wheel 502 is fixed to the nut 504 by a bearing screw 503. The wheel 502 can rotate freely around the bearing screw 503. The wheel 502 can be integrally formed or machined, and the materials include but are not limited to nylon, ABS, BOM, etc. The middle of the wheel support 500 is provided with a symmetrically centered and freely rotatable rotating shaft 505 for installation on the first shaft hole 103. The installation method is interference fit. The material of the rotating shaft 505 is 45 carbon steel, stainless steel or POM. On the wheel support 500 between the rotating shaft 505 and the nut 504, there are symmetrically arranged limiting inclined planes 501 on both sides. The included angle between the two inclined planes is exactly equal to the included angle of the first limiting groove 102 on the forward power support 1, which plays a role in circumferential limiting of the power wheel module 5. In addition, a cut-off surface 507 is provided at the intersection of the limiting inclined planes 501. The function of this surface is to prevent insufficient contact between the limiting inclined plane 501 and the first limiting groove 102 caused by machining errors, or to avoid excessive constraints and functional failures.

[0065] The other end of the wheel support 500 is provided with a spring fixing hole 506 for installing one end of the spring 9. The other end of the spring 9 is installed on the cross beam 600 on the front cover 6 or the corresponding hook on the lateral power support 2. Further, there are three cross beams 600 on the front cover 6, as Figure 5 、 8 shown in the figure. The material of the front cover 600 can be selected from nylon, ABS, acrylic, etc.

[0066] Under the action of the spring 9, the entire power wheel module 5 can rotate around the rotating shaft 505. In the free state of the spring 9, the power wheel module 5 is in an unfolded state, and the position corresponds to Figure 1 shown in the figure.

[0067] Similar to the forward power support 1, the main function of the lateral power support 2 is also support and connection. The overall structure is similar to two intersecting cylinders, and it is provided with a rear power wheel support 200, a second movable groove 201, a second limiting groove 202, a second shaft hole 203, a lateral thruster fixing seat 204, a gland fixing seat 205, a connecting bracket 206, and a hook 207, as Figure 6 、 7As shown in the figure. The overall structure of the lateral power support 2 can be integrally formed or machined, and the materials include but are not limited to nylon, aluminum alloy, carbon fiber, etc. The rear power wheel support 200 is used to support the power wheel module 5. In the embodiment of the present invention, six groups of power wheel modules 5 are adopted, with 3 groups installed on the forward power support 1 and the remaining three groups installed on the lateral power support 2. Similar to the forward power support 1, there are also three symmetrically distributed rear power wheel supports 200 on the lateral power support 2. One end of the three rear power wheel supports 200 is connected to the lateral thruster fixing seat 204. The lateral thruster fixing seat 204 is integrally cylindrical, and on the other side, there is a connecting bracket 206 connected to the forward power support 1. The lateral power module 11 is installed in the middle of the lateral thruster fixing seat 204, and the power direction is perpendicular to the direction of the forward power module 10. When working, the lateral power module 11 generates lateral power. The lateral power module 11 can adopt a standard underwater thruster, and the embodiment of the present invention does not make further restrictions.

[0068] The rear power wheel support 200 is provided with a second movable groove 201, a second limiting groove 202, a second shaft hole 203, and a gland fixing seat 205. The structures and functions of the second movable groove 201, the second limiting groove 202, and the second shaft hole 203 are the same as those of the first movable groove 101, the first limiting groove 102, and the first shaft hole 103, and will not be repeated here. Inside the rear power wheel support 200, away from the end of the second limiting groove 202, there is a hook 207 for connecting with one end of the spring 9. The spring 9 has a pulling force between the hook 207 and the spring fixing hole 506, so as to ensure that the power wheel module 5 is always in the position as shown in Figure 8 In the figure, the gland fixing seat 205 is used to fixedly install the gland 7, and the gland 7 is used to fix the cable 8.

[0069] When the device is put into use, the six groups of power wheel modules 5 need to be manually bent inward at an angle of 90 degrees, so as to reduce the overall external dimension. As shown in Figure 9 、 10 When the power wheel module 5 rotates to the limit, the effective outer diameter of the entire device only depends on the outer diameter of the forward power support 1, and the outer diameter of the forward power support 1 can be set according to the size of the forward power module 10. After the outer diameter is reduced, the device can pass through a DN100 or smaller gate valve on the pipeline, which brings great convenience to the placement. After entering the pipeline, under the action of the spring 9, the power wheel module 5 returns to the position as shown in Figure 1 In the figure. Since the designed power wheel module 5 can only be retracted in the direction away from the cable 8, when the device is retrieved, the power wheel module 5 automatically closes inward under the action of the narrow inner wall of the placement opening such as the gate valve, so that the entire device can be smoothly retrieved without other auxiliary power.

[0070] The entire device relies on the front buoyancy block 3 and the rear buoyancy block 4 to achieve a zero-buoyancy state inside the pipeline. The structures of the front buoyancy block 3 and the rear buoyancy block 4 are slightly different, but the structural principles are the same. In this embodiment, the front buoyancy block 3 is used as an example for illustration. As Figure 11 shown, the buoyancy block 3 adopts a thin-walled hollow structure and can be integrally formed by 3D printing with resin material, or formed by separate injection molding and then adhered together. The internal chamber of the integrally formed buoyancy block 3 is filled with air, thereby increasing the buoyancy of the entire device. Three buoyancy blocks 3 and three rear buoyancy blocks 4 are required respectively, and they are installed in the middle of three groups of front power wheel brackets 100 and three groups of rear power wheel brackets 200. As Figure 1 shown, the installation method can adopt bonding or other mechanical fixing methods.

[0071] As Figure 12 shown, the two groups of power wheel modules 5 installed on the front and rear power wheel brackets respectively form an equilateral triangle structure, and the front and rear triangles coincide. To facilitate distinguishing the relative positions and analyzing the motion modes, the power wheel modules 5 in the view are denoted as A, B, and C. At the same time, it is stipulated that the power wheel module 5 with the same power direction as the lateral power module 11 is located at A.

[0072] Figure 13 shows the motion mode of the entire device on a flat ground when the lateral power module 11 provides a downward power F. In the figure, the middle device is defaulted to the initial state. At this time, the direction of the force F coincides with the center of the power wheel module 5 at A. Since the center of the force application point of the device is above the power wheel module 5, and the wheel 502 on the power wheel module 5 is approximately in point contact with the ground, the entire device is unstable under force, and the entire device will tilt and fall to one side under a very small disturbance, and the probability of falling to the left or to the right is the same. Figure 13 The left figure in

[0073] shows the result after falling to the right. y force and the F x force parallel to the ground. The F x force pushes the device to move to the left. Figure 13 The right figure in y shows the result after the device falls to the left. Under the action of the force F, the device generates a F x force perpendicular to the ground and a F x force parallel to the ground. The F

[0074] Figure 14 will Figure 13The ground in the figure is replaced with the inner wall of a partial pipeline. The direction perpendicular to the picture in the figure represents the direction of fluid movement in the pipeline, which is also the moving direction when the device moves forward. When the device needs to move along the circumference of the pipe wall, the lateral power module 11 is turned on, so that the whole device is subjected to a downward force F (relative to the device in the figure). The force F in the figure is equivalent to the force pointing to the power wheel module 5 at point A. Under the action of the force F, the device moves laterally towards the pipe wall. The lateral movement structure is as Figure 14 shown by the device in the middle position. Here, the device and Figure 13 in the plane situation as shown, it will randomly fall to both sides due to unstable force. After falling, it can rotate clockwise or counterclockwise along the pipe wall. Since the device is in a zero buoyancy state in the pipeline, during the whole circular motion process, the force F y always provides the centripetal force for the circular motion of the device, and the force F x provides the tangential force to overcome the fluid resistance for the movement along the pipe wall. During the movement, the device always maintains an equidistant movement from the pipe wall, thus providing an ideal platform for further detecting the pipe wall. This method realizes the mode of circular motion along the pipe wall without using a complex servo to control the device, and the randomness of its running direction ensures that the counterclockwise and clockwise movements are equally probable, which further protects the twisting force of the cable at the end of the device and does not require connection mechanisms such as electric slip rings.

[0075] Furthermore, when the lateral power module 11 is turned on in the reverse direction, the whole device is subjected to an upward force, denoted as -F. The result of the lateral movement of the device is as Figure 15 shown. At this position, the device is subjected to an upward thrust and is balanced with the reaction force of the pipe wall, and the device enters a stationary state fitting the pipe wall. This mode is beneficial for carefully observing the inner surface of the pipe.

[0076] In the embodiments of the present invention, except for those with special descriptions for the models of each device, the models of other devices are not limited, as long as the devices can perform the above functions.

[0077] Those skilled in the art can understand that the drawings are only schematic diagrams of a preferred embodiment. The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[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, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A motion device for detecting the inner surface of a pressurized pipeline, characterized in that The device includes: a forward power support and a lateral power support, Three front buoyancy blocks and three groups of power wheel modules are respectively installed in front of the forward power support, and a front cover is installed at the end. A forward power module is installed inside the forward power support. The lateral power support is connected to the rear end of the forward power support, and three rear buoyancy blocks and three groups of power wheel modules are provided at the other end of the lateral power support; A lateral power module is arranged between the lateral power support and the filter screen, and the installation direction of the lateral power module is consistent with the installation direction of one of the groups of power wheel modules; Among them, three groups of front power wheel supports are symmetrically distributed on the forward power support, and the geometric centers of the three groups of front power wheel supports coincide with the center of the forward power support; Among them, three groups of rear power wheel supports are symmetrically distributed on the lateral power support. One end of the three groups of rear power wheel supports is connected to the lateral thruster fixing seat, and a connecting support connected to the forward power support is provided on the other side. The lateral power module is installed in the middle of the lateral thruster fixing seat, and the power direction is perpendicular to the direction of the forward power module; Two vertically placed power modules, the forward power module provides forward power, and the lateral power module provides lateral power. Under the action of the lateral power module, the device realizes the functions of circular motion along the pipe wall clockwise or counterclockwise and sticking to the pipe wall to keep still; The zero buoyancy state in the device pipeline is achieved by relying on the front buoyancy blocks and the rear buoyancy blocks; the two groups of power wheel modules installed on the front and rear power wheel supports respectively form an equilateral triangle structure, and the front and rear triangles coincide; the lateral power module rotates forward and backward; at most two of the power wheel modules forming the same triangle are in contact with the pipe wall.

2. The in-pipe surface inspection motion device for pressurized pipes according to claim 1, wherein, The front power wheel support is provided with a first movable groove, a first limiting groove, a first shaft hole and a front cover seat, The first movable groove is located in the middle of the front power wheel support and is used for passing through the power wheel module. First shaft holes are provided on both sides of the first movable groove for supporting the power wheel module. A first limiting groove is provided at the bottom of the first movable groove for limiting the power wheel module.

3. The inner surface inspection moving device for a pressurized pipeline according to claim 1 or 2, characterized in that, The power wheel module includes: a wheel support, One end of the wheel support is provided with a nut for fixing the wheel, and the nut is embedded inside the support. A rotatable rotating shaft is symmetrically centered in the middle of the wheel support for installing on the first shaft hole. Limiting inclined surfaces are symmetrically provided on both sides of the wheel support between the rotating shaft and the nut, and the included angle between the two inclined surfaces is exactly equal to the included angle of the first limiting groove on the forward power support. A cut-off surface is provided at the intersection of the limiting inclined surfaces; The other end of the wheel support is provided with a spring fixing hole for installing one end of the spring, and the other end of the spring is installed on the cross beam of the front cover or the corresponding hook on the lateral power support.

4. A movement device for detecting the inner surface of a pressurized pipeline according to claim 1, characterized in that, The rear power wheel support is provided with a second movable groove, a second limiting groove, a second shaft hole and a gland fixing seat. A hook is provided at the end of the rear power wheel support away from the second limiting groove for connecting with one end of the spring.

5. A motion device for detecting the inner surface of a pressurized pipeline according to claim 1, characterized in that, The device is also provided with a rear buoyancy block, which is installed in the middle of the three groups of rear power wheel supports, Both the front and rear buoyancy blocks adopt a thin-walled hollow structure and are integrally formed by 3D printing with resin materials, or are formed by separate injection molding and then adhered together. The internal chamber of the integrally formed buoyancy block is filled with air.

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