Spherical tank welding seam magnetization array eddy current wall-climbing detection robot

Abstract

A spherical tank welding seam magnetization array eddy current wall-climbing detection robot disclosed by the present invention comprises a vehicle frame, two wheels, a driving mechanism and a detection mechanism, the two wheels are rotatably arranged on the vehicle frame at an interval, the two wheels are permanent magnets, the inner rings and the outer rings of the wheels have different magnetisms, and the driving mechanism and the detection mechanism are arranged on the vehicle frame. And the inner rings of the two wheels are opposite in magnetism. The array eddy current detection mechanism has the beneficial effects that the magnetic fields of the two permanent magnets form a magnetic circuit in a detected welding seam area, and the magnetic fields uniformly diffused to the periphery of the two permanent magnets are gathered in the magnetic circuit in the detected welding seam area, so that the interference of the peripheral diffused magnetic fields on the detection mechanism is reduced, and the stability of array eddy current detection signals is ensured; the magnetic flux density of the detected welding seam area can be increased, the detected welding seam area is further magnetized, the relative permeability of the detected welding seam area is reduced, the detection depth of the array eddy current detection signal can be greatly increased, and therefore cracks in the deep position of the welding seam can be detected.

Description

Technical Field

[0001] The invention relates to the technical field of spherical tank weld detection, and in particular to a spherical tank weld magnetization array eddy current wall climbing detection robot. Background Art

[0002] As special pressure-bearing storage equipment, large industrial spherical tanks are usually more than ten meters in diameter and are welded from multiple sets of thick steel plates. Due to corrosion of stored materials, changes in internal pressure, release of welding stress and other reasons, internal defects and damage may occur at the weld joints, affecting the safe use of spherical tank equipment. At present, with the continuous development of non-destructive testing technologies such as digital flat-panel radiography (DR) and ultrasonic TOFD, there are incomparable advantages in detection reliability, result traceability, and operation efficiency. However, the on-site implementation and application of these new non-destructive testing technologies rely heavily on efficient and reliable technical process equipment. Wall-climbing robots can carry equipment and tools to operate in high-altitude spherical tank environments for automated inspection and maintenance, effectively reducing the labor intensity of personnel and the risk of accidents at high altitudes, and improving inspection efficiency.

[0003] The existing spherical tank weld inspection wall-climbing robots (such as a multi-drive wheel combined curved surface adaptive spherical tank inspection robot disclosed in application number 202310866271.4) have a shallow signal detection depth and are difficult to detect cracks deep in the weld. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned technical deficiencies and propose a spherical tank weld magnetization array eddy current wall climbing detection robot to solve the technical problem that the robot signal detection depth in the prior art is shallow and it is difficult to detect cracks deep in the weld.

[0005] In order to achieve the above technical objectives, the technical solution of the present invention provides a spherical tank weld magnetization array eddy current wall climbing detection robot, comprising: Frame; Two wheels are rotatably arranged on the frame at an interval, both wheels are permanent magnets, the inner ring and the outer ring of the wheels have different magnetic properties, the inner rings of the two wheels have opposite magnetic properties, and the outer rings of the two wheels have opposite magnetic properties; A driving mechanism connected to both wheels, and used to drive the two wheels to rotate so as to make the frame move forward, backward or turn; The detection mechanism is arranged on the vehicle frame and located between the two wheels, and is used for transmitting array eddy current detection signals to the weld area between the two wheels.

[0006] Furthermore, the frame includes a front frame and a rear frame, the front frame and the rear frame are spaced apart, and the mutually adjacent ends of the front frame and the rear frame are rotationally connected via a rotating shaft, and the two wheels are rotationally arranged on the front frame and the rear frame respectively.

[0007] Furthermore, the two wheels each include a central axis, a wheel body and two side plates, the wheel body is sleeved on the central axis, the two side plates are both detachably fixedly sleeved on the central axis, and are respectively arranged on both sides of the wheel body, and the two side plates are also detachably fixedly connected to the wheel body.

[0008] Furthermore, the wheel body is a permanent magnet, and the central axis and the two side plates are made of non-magnetic materials.

[0009] Furthermore, the diameter of the wheel body gradually increases from the middle to both ends.

[0010] Furthermore, the driving mechanism includes two first driving assemblies and a second driving assemblies, the two first driving assemblies are respectively connected to the two wheels, and are used to drive the two wheels to rotate in the same direction and at the same speed so that the frame moves forward or backward, and the two ends of the second driving assembly are respectively connected to the front frame and the rear frame, and are used to drive the front frame to swing back and forth around its rotating axis toward both sides of the rear frame so that the frame turns.

[0011] Furthermore, the two first drive components each include a first rotating drive member and a transmission component, the two first rotating drive members are respectively fixed on the front frame and the rear frame, one end of the two transmission components are respectively connected to the output end of the corresponding first rotating drive member, and the other end of the two transmission components are respectively connected to the corresponding wheels to convert the rotation of the corresponding output end of the first rotating drive member into the rotation of the corresponding wheel.

[0012] Furthermore, the second driving assembly includes a second rotating driving member, which is fixed on the rear frame, and an output end of the second rotating driving member is fixedly connected to the rotating axis of the front frame, so as to drive the front frame to swing back and forth around its rotating axis toward both sides of the rear frame.

[0013] Furthermore, the detection mechanism is arranged between the front frame and the rear frame, and the detection mechanism includes a probe and two telescopic driving members. The probe can emit an array eddy current detection signal. The two telescopic driving members are fixed on the rear frame, and the output ends of the two telescopic driving members are fixedly connected to the probe for driving the probe to move up and down so that the probe can be lowered or retracted.

[0014] Furthermore, the spherical tank weld magnetized array eddy current wall-climbing detection robot also includes a control mechanism, which is arranged on the frame and is electrically connected to the driving mechanism and the detection mechanism, and is used to output control signals to the driving mechanism and the detection mechanism and receive and process the weld information detected by the detection mechanism.

[0015] Compared with the prior art, the beneficial effects of the present invention include: when in use, the robot is placed on the surface of the spherical tank. Since the spherical tank is made of iron and the wheels are permanent magnets, the wheels are adsorbed on the surface of the spherical tank due to magnetic force. The robot moves forward, backward or turns on the surface of the spherical tank and can move to the weld area to be detected. When the wall-climbing robot is adsorbed on the surface of the spherical tank and reaches the weld area to be detected, since the inner rings of the two wheels have opposite magnetism and the outer rings of the two wheels have opposite magnetism, the magnetic fields of the two permanent magnets form a magnetic circuit in the weld area to be detected. The two permanent magnets evenly diffuse the magnetic field around and gather in the magnetic circuit of the weld area to be detected, reducing the interference of the diffused magnetic field around on the detection mechanism, ensuring the stability of the array eddy current detection signal, and being able to increase the magnetic flux density of the weld area to be detected, further magnetize the weld area to be detected, and reduce the relative magnetic permeability of the weld area to be detected. It can be seen from the skin depth formula of the induced current: When other detection conditions remain unchanged, reducing the relative magnetic permeability μ can greatly increase the detection depth of the array eddy current detection signal, thereby detecting cracks deep in the weld. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional structural schematic diagram of a spherical tank weld magnetization array eddy current wall climbing detection robot provided by the present invention; Figure 2 yes Figure 1 A schematic diagram of the three-dimensional structure of a wheel in a spherical tank weld magnetization array eddy current wall climbing inspection robot; Figure 3 It is a schematic diagram of magnetizing the weld area by two wheels in a spherical tank weld magnetization array eddy current wall climbing inspection robot provided by the present invention; Figure 4 It is a detection simulation diagram under different magnetization intensities provided by the present invention; In the figure: 100 - frame, 110 - front frame, 120 - rear frame, 200 - wheel, 210 - central axis, 220 - wheel body, 230 - side plate, 300 - driving mechanism, 310 - first driving assembly, 311 - first rotating driving member, 312 - transmission assembly, 320 - second driving assembly, 321 - second rotating driving member, 400 - detection mechanism, 410 - probe, 420 - telescopic driving member. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0018] The present invention provides a spherical tank weld magnetization array eddy current wall climbing detection robot, the structure of which is as follows: Figure 1 - Figure 3 As shown, it includes a frame 100, two wheels 200, a driving mechanism 300 and a detection mechanism 400. The two wheels 200 are arranged on the frame 100 at an interval and rotated. The two wheels 200 are permanent magnets. The inner ring and the outer ring of the wheel 200 have different magnetism. The inner rings of the two wheels 200 have opposite magnetism, and the outer rings of the two wheels 200 have opposite magnetism. The driving mechanism 300 is connected to the two wheels 200 and is used to drive the two wheels 200 to rotate so that the frame 100 moves forward, backward or turns. The detection mechanism 400 is arranged on the frame 100 and is located between the two wheels 200 to emit an array eddy current detection signal to the weld area between the two wheels 200.

[0019] When in use, the robot is placed on the surface of the spherical tank. Since the spherical tank is made of iron, the wheel 200 is a permanent magnet. The wheel 200 is adsorbed on the surface of the spherical tank due to magnetic force. The robot moves forward, backward or turns on the surface of the spherical tank and can move to the weld area to be detected. When the wall-climbing robot is adsorbed on the surface of the spherical tank and reaches the weld area to be detected, since the inner rings of the two wheels 200 have opposite magnetism and the outer rings of the two wheels 200 have opposite magnetism, the magnetic fields of the two permanent magnets form a magnetic circuit in the weld area to be detected. The two permanent magnets evenly diffuse the magnetic field around and gather in the magnetic circuit of the weld area to be detected, reducing the interference of the diffuse magnetic field around on the detection mechanism 400, ensuring the stability of the array eddy current detection signal, and can increase the magnetic flux density of the weld area to be detected, further magnetize the weld area to be detected, and reduce the relative magnetic permeability of the weld area to be detected. It can be seen from the induced current skin depth formula: When other detection conditions remain unchanged, reducing the relative magnetic permeability μ can greatly increase the detection depth of the array eddy current detection signal, thereby detecting cracks deep in the weld.

[0020] As a preferred embodiment, please refer to Figure 1The frame 100 includes a front frame 110 and a rear frame 120, the front frame 110 and the rear frame 120 are spaced apart, and the mutually adjacent ends of the front frame 110 and the rear frame 120 are rotationally connected via a rotating shaft, and the two wheels 200 are rotationally arranged on the front frame 110 and the rear frame 120, respectively, so that the front frame 110 and the rear frame 120 can rotate relative to each other, which is convenient for realizing the steering function, so that the wall-climbing robot can crawl on surfaces with different curvatures.

[0021] As a preferred embodiment, please refer to Figure 2 The two wheels 200 each include a central axis 210, a wheel body 220 and two side plates 230. The wheel body 220 is sleeved on the central axis 210. The two side plates 230 are both detachably fixedly sleeved on the central axis 210 and are respectively arranged on both sides of the wheel body 220. The two side plates 230 are also detachably fixedly connected to the wheel body 220, which facilitates the disassembly and assembly of the structure of the wheel 200 and the timely replacement of the wheel body 220.

[0022] As a preferred embodiment, the wheel body 220 is a permanent magnet, the inner ring and the outer ring of the wheel body 220 have different magnetism, the inner rings of the two wheel bodies 220 have opposite magnetism, the outer rings of the two wheel bodies 220 have opposite magnetism, and the center axis 210 and the two side plates 230 are made of non-magnetic materials, which facilitates the disassembly and assembly of the structure of the wheel 200 and the timely replacement of the wheel body 220, so that the wheel 200 can maintain a high magnetism.

[0023] As a preferred embodiment, please refer to Figure 2 The diameter of the wheel body 220 gradually increases from the middle to both ends. Since the surface of the weld area is uneven, if the wheel 200 is a traditional cylindrical structure, the wheel 200 is prone to shake during driving. The diameter of the wheel body 220 gradually increases from the middle to both ends, which can improve the stability of the wheel 200 during driving, thereby improving the stability of the detection mechanism 400 and avoiding the lifting change of the detection mechanism 400 caused by shaking. The lifting change refers to the distance between the detection mechanism 400 and the surface of the spherical tank, which ensures that the signal will not be missed or misdetected, and can also ensure that when the wheel 200 is driving on the weld, the wheel 200 can better fit the surface of the spherical tank, and the magnetic lines of force in the permanent magnet are more evenly and vertically introduced into the inspected area, so as to better form a new magnetic circuit.

[0024] As a preferred embodiment, please refer to Figure 4, a crack defect with a buried depth of 5.0mm and a length×width×depth=10.0mm×1.0mm×3.0mm was detected and simulated under different magnetization intensities of the permanent magnet. The simulation results show that when there is no magnetization, the buried defect cannot be detected. When the magnet is magnetized and a certain magnetization intensity is reached, the signal peak of the buried defect increases with the increase of the magnetization intensity. The magnetic circuit design of the wheel 200 enhances the detection depth of the signal.

[0025] As a preferred embodiment, please refer to Figure 1 The driving mechanism 300 includes two first driving assemblies 310 and a second driving assembly 320. The two first driving assemblies 310 are respectively connected to the two wheels 200 to drive the two wheels 200 to rotate in the same direction and at the same speed so that the frame 100 moves forward or backward. The two ends of the second driving assembly 320 are respectively connected to the front frame 110 and the rear frame 120 to drive the front frame 110 to swing back and forth around its rotation axis to the two sides of the rear frame 120 so that the frame 100 turns. The first driving components 310 are started synchronously to drive the two wheels 200 to rotate in the same direction and at the same speed, so that the frame 100 can move forward. The two first driving components 310 are started synchronously to drive the two wheels 200 to rotate in the same direction and at the same speed, so that the frame 100 can move backward. The second driving components 320 are started to drive the front frame 110 to swing back and forth around its rotation axis toward the two sides of the rear frame 120, so that the frame 100 can turn, and the wall-climbing robot can crawl freely on the surface of the spherical tank.

[0026] As a preferred embodiment, please refer to Figure 1The two first driving components 310 each include a first rotating driving member 311 and a transmission component 312. The two first rotating driving members 311 are respectively fixed to the front frame 110 and the rear frame 120. One end of the two transmission components 312 is respectively connected to the output end of the corresponding first rotating driving member 311. The other end of the two transmission components 312 is respectively connected to the corresponding wheel 200 to convert the rotation of the output end of the corresponding first rotating driving member 311 into the rotation of the corresponding wheel 200. The other end of the two transmission components 312 is respectively connected to one end of the central axis 210 of the corresponding wheel 200. The two first rotating driving members 311 are respectively fixed to the front frame 110 and the rear frame 120. One end of the two transmission components 312 is respectively connected to the output end of the corresponding first rotating driving member 311. The other end of the two transmission components 312 is respectively connected to one end of the central axis 210 of the corresponding wheel 200. 11 are started synchronously. When the output ends of the two first rotating drive members 311 rotate forward synchronously, the positive rotation of the corresponding output end of the first rotating drive member 311 can be converted into the positive rotation of the corresponding wheel 200 via the corresponding transmission assembly 312, so that the frame 100 can be moved forward. When the output ends of the two first rotating drive members 311 rotate backward synchronously, the positive rotation of the corresponding output end of the first rotating drive member 311 can be converted into the reverse rotation of the corresponding wheel 200 via the corresponding transmission assembly 312, so that the frame 100 can be moved backward. The transmission assembly 312 is a pulley transmission, which will not be described in detail in this solution.

[0027] As a preferred embodiment, please refer to Figure 1 The second driving assembly 320 includes a second rotating driving member 321, which is fixed on the rear frame 120. The output end of the second rotating driving member 321 is fixedly connected to the rotating axis of the front frame 110, and is used to drive the front frame 110 to swing back and forth around its rotating axis toward the two sides of the rear frame 120. When the second rotating driving member 321 is started, when the output end of the second rotating driving member 321 rotates forward, the front frame 110 can be driven to rotate around its rotating axis to one side of the rear frame 120. When the output end of the second rotating driving member 321 rotates reversely, the front frame 110 can be driven to rotate around its rotating axis to the other side of the rear frame 120, thereby making the frame 100 turn.

[0028] As a preferred embodiment, please refer to Figure 1The detection mechanism 400 is arranged between the front frame 110 and the rear frame 120. The detection mechanism 400 includes a probe 410 and two telescopic driving members 420. The probe 410 can emit array eddy current detection signals. The two telescopic driving members 420 are fixed on the rear frame 120. The output ends of the two telescopic driving members 420 are fixedly connected to the probe 410, which is used to drive the probe 410 to move up and down so that the probe 410 can be lowered or folded. When detection is required, the probe 410 is lowered. When detection is not required or obstacles are crossed, the probe 410 box is folded to avoid collision of the probe 410.

[0029] As a preferred embodiment, the spherical tank weld magnetization array eddy current wall-climbing detection robot also includes a control mechanism, which is arranged on the frame 100 and is electrically connected to the drive mechanism 300 and the detection mechanism 400, and is used to output control signals to the drive mechanism 300 and the detection mechanism 400 and receive and process the weld information detected by the detection mechanism 400. The output end of the control mechanism is electrically connected to the two first rotating drive members 311, the second rotating drive member 321 and the two telescopic drive members 420, and is used to control the start and stop of the two first rotating drive members 311, the second rotating drive member 321 and the two telescopic drive members 420. The input end of the control mechanism is electrically connected to the probe 410, and is used to receive and process the weld information detected by the probe 410. The control mechanism is an electronic control system and will not be described in detail in this scheme.

[0030] In order to better understand the present invention, the following Figure 1 - Figure 3 The working principle of the technical solution of the present invention is described in detail: When in use, the robot is placed on the surface of the spherical tank. Since the spherical tank is made of iron, the wheel body 220 is a permanent magnet. The wheel body 220 is adsorbed on the surface of the spherical tank due to magnetic force. The robot moves forward, backward or turns on the surface of the spherical tank and can move to the weld area to be detected. When the wall-climbing robot is adsorbed on the surface of the spherical tank and reaches the weld area to be detected, since the inner rings of the two wheel bodies 220 have opposite magnetism and the outer rings of the two wheel bodies 220 have opposite magnetism, the magnetic fields of the two permanent magnets form a magnetic circuit in the weld area to be detected. The two permanent magnets evenly diffuse the magnetic field around and gather in the magnetic circuit of the weld area to be detected, reducing the interference of the diffused magnetic field around on the detection mechanism 400, ensuring the stability of the array eddy current detection signal, and can increase the magnetic flux density of the weld area to be detected, further magnetize the weld area to be detected, and reduce the relative magnetic permeability of the weld area to be detected. It can be seen from the induced current skin depth formula: When other detection conditions remain unchanged, reducing the relative magnetic permeability μ can greatly increase the detection depth of the array eddy current detection signal, thereby detecting cracks deep in the weld.

[0031] The spherical tank weld magnetization array eddy current wall climbing detection robot provided by the present invention has the following beneficial effects: (1) The diameter of the wheel body 220 gradually increases from the middle to both ends, which can improve the stability of the wheel 200 during driving, thereby improving the stability of the detection mechanism 400 and avoiding the lifting change of the detection mechanism 400 caused by shaking. The lifting change refers to the distance between the detection mechanism 400 and the surface of the spherical tank, which ensures that the signal will not be missed or misdetected. It can also ensure that when the wheel 200 drives on the weld, the wheel 200 can better fit the surface of the spherical tank, and the magnetic lines of force in the permanent magnet are more evenly and vertically introduced into the detected area, so as to better form a new magnetic circuit; (2) This wall-climbing inspection robot uses non-contact array eddy current inspection for spherical tank welds, which has the advantages of high precision and high efficiency, and does not require pretreatment of the spherical tank surface. It can adapt to different spherical tank curvatures and can replace manual inspection; (3) The magnetic fields of the two permanent magnets form a magnetic circuit in the weld area to be inspected. The two permanent magnets evenly diffuse the magnetic fields in the surrounding areas and gather in the magnetic circuit in the weld area to be inspected, thereby reducing the interference of the diffused magnetic fields in the surrounding areas on the detection mechanism 400, ensuring the stability of the array eddy current detection signal, and increasing the magnetic flux density in the weld area to be inspected, further magnetizing the weld area to be inspected, reducing the relative magnetic permeability of the weld area to be inspected, and greatly increasing the detection depth of the array eddy current detection signal, thereby detecting cracks deep in the weld.

[0032] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A spherical tank weld magnetization array eddy current wall climbing detection robot, characterized in that: include: Frame; Two wheels are rotatably arranged on the frame at an interval, both wheels are permanent magnets, the inner ring and the outer ring of the wheels have different magnetic properties, the inner rings of the two wheels have opposite magnetic properties, and the outer rings of the two wheels have opposite magnetic properties; A driving mechanism connected to both wheels, and used to drive the two wheels to rotate so as to make the frame move forward, backward or turn; The detection mechanism is arranged on the vehicle frame and located between the two wheels, and is used for transmitting array eddy current detection signals to the weld area between the two wheels.

2. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 1 is characterized in that: The frame comprises a front frame and a rear frame, wherein the front frame and the rear frame are spaced apart from each other, and the mutually adjacent ends of the front frame and the rear frame are rotationally connected via a rotating shaft, and the two wheels are rotationally arranged on the front frame and the rear frame respectively.

3. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 1 is characterized in that: The two wheels each include a central axis, a wheel body and two side plates. The wheel body is sleeved on the central axis. The two side plates are both detachably and fixedly sleeved on the central axis and are respectively arranged on both sides of the wheel body. The two side plates are also detachably fixedly connected to the wheel body.

4. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 3 is characterized in that: The wheel body is a permanent magnet, and the central axis and the two side plates are made of non-magnetic materials.

5. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 3 is characterized in that: The diameter of the wheel body gradually increases from the middle to both ends.

6. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 2 is characterized in that: The driving mechanism includes two first driving assemblies and a second driving assembly. The two first driving assemblies are respectively connected to the two wheels to drive the two wheels to rotate in the same direction and at the same speed so that the frame moves forward or backward. The two ends of the second driving assembly are respectively connected to the front frame and the rear frame to drive the front frame to swing back and forth around its rotation axis to the two sides of the rear frame so that the frame turns.

7. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 6 is characterized in that: The two first drive components each include a first rotating drive member and a transmission component. The two first rotating drive members are respectively fixed on the front frame and the rear frame. One end of the two transmission components are respectively connected to the output end of the corresponding first rotating drive member, and the other end of the two transmission components are respectively connected to the corresponding wheels to convert the rotation of the corresponding output end of the first rotating drive member into the rotation of the corresponding wheel.

8. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 6 is characterized in that: The second driving assembly includes a second rotating driving member, which is fixed on the rear frame. The output end of the second rotating driving member is fixedly connected to the rotating axis of the front frame to drive the front frame to swing back and forth around its rotating axis toward both sides of the rear frame.

9. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 2 is characterized in that: The detection mechanism is arranged between the front frame and the rear frame, and includes a probe and two telescopic driving members. The probe can emit array eddy current detection signals. The two telescopic driving members are fixed on the rear frame, and the output ends of the two telescopic driving members are fixedly connected to the probe for driving the probe to move up and down so that the probe can be lowered or retracted.

10. The spherical tank weld magnetization array eddy current wall climbing detection robot according to claim 1, characterized in that: It also includes a control mechanism, which is arranged on the frame and electrically connected to the driving mechanism and the detection mechanism, and is used to output control signals to the driving mechanism and the detection mechanism and receive and process the weld information detected by the detection mechanism.

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