Magnetic flux leakage scanning device

Abstract

The invention provides a magnetic flux leakage scanning device which comprises a magnetic bridge, a driving wheel assembly, a driving mechanism used for driving a driving wheel of the driving wheel assembly to rotate, a first excitation unit and a second excitation unit, the first excitation unit and the second excitation unit are meshed with the driving wheel, and a first permanent magnet and a second permanent magnet are arranged in the first excitation unit and the second excitation unit respectively. The magnetic bridge can communicate the magnetic poles of the first permanent magnet and the second permanent magnet to form a loop, and the driving wheel rotates to drive the first excitation unit and the second excitation unit to rotate, so that the magnetic poles of the first permanent magnet and the second permanent magnet change the orientation relative to the magnetic bridge and the distance from the end of each magnetic pole to the magnetic bridge. The magnetisability and the magnetic attraction force of the magnetic flux leakage scanning device are adjustable, so that the operation of the magnetic flux leakage scanning device is simplified, the detection application range is expanded, and the detection efficiency and the system signal-to-noise ratio are improved.

Description

Technical Field

[0001] The present invention relates to the field of nondestructive testing equipment design and operation, and in particular to a magnetic flux leakage scanning device. Background Art

[0002] Industrial storage tanks are large containers used to hold industrial products such as crude oil, intermediate oil, and finished oil. The bottom plate of the tank is prone to failure due to the dual erosion of corrosive media and water vapor. Usually, it is necessary to scan and test the bottom plate of the tank to determine whether it affects the use. Magnetic flux leakage detection is the most commonly used technology for detecting the bottom plate of the tank. With the increasing number of large storage tanks, the thickness of the bottom plate of the tank has also increased. Therefore, it is necessary to increase the excitation unit of the magnetic flux leakage scanning device to provide a stronger magnetic field.

[0003] The existing excitation unit usually fixes two rows of permanent magnets at the front and rear ends of the magnetic bridge. To form a magnetic circuit, the lower surfaces of the two rows of permanent magnets (that is, the side close to the bottom plate of the tank) are the S pole and the N pole respectively. The sensor strip is suspended in the middle position of the magnetic bridge. During detection, the excitation unit scans across the upper surface of the bottom plate of the tank. Since the permanent magnet is fixed relative to the magnetic bridge in the design of this excitation unit, its magnetization ability to the tank bottom plate is also fixed. For tank bottom plates with a large thickness (for example, greater than 20 mm), the leakage magnetic flux scanning device has the following disadvantages due to the need to use an excitation unit with a strong magnet: the attraction between the leakage magnetic flux scanning device and the tank bottom plate increases. When the leakage magnetic flux scanning device is repeatedly pried up and lowered, the operator needs to use his feet to support the tank bottom plate, and then skillfully move and exert force to pry up the leakage magnetic flux scanning device. In the process of lowering it after turning around, a large impact is formed between the leakage magnetic flux scanning device and the bottom plate, which can easily cause the tank bottom plate to flip up; the burden on the traction motor increases, and the energy of the battery used by the leakage magnetic flux scanning device is consumed too quickly, which slows down the scanning speed and thus reduces the detection efficiency; the tank bottom plate is magnetized, and a leakage magnetic field appears on the bottom plate and the background magnetic field increases, which in turn leads to a decrease in the signal-to-noise ratio of the leakage magnetic flux scanning device and a decrease in the scanning ability. Summary of the invention

[0004] An object of the present invention is to provide a magnetic flux leakage scanning device, so as to simplify the operation of the magnetic flux leakage scanning device, expand the detection application range, and improve the detection efficiency and system signal-to-noise ratio by making the magnetization ability and magnetic attraction force of the magnetic flux leakage scanning device adjustable.

[0005] According to the present invention, a magnetic flux leakage scanning device is provided, comprising: a magnetic bridge, a driving wheel assembly, a driving mechanism for driving the driving wheel of the driving wheel assembly to rotate, and a first excitation unit and a second excitation unit engaged with the driving wheel. The interiors of the first excitation unit and the second excitation unit respectively have a first permanent magnet and a second permanent magnet. The magnetic bridge can connect the magnetic poles of the first permanent magnet and the second permanent magnet into a loop. The driving wheel drives the first excitation unit and the second excitation unit to rotate through rotation, so that the orientation of the magnetic poles of the first permanent magnet and the second permanent magnet relative to the magnetic bridge and the distance between the ends of the magnetic poles and the magnetic bridge are changed.

[0006] In a preferred embodiment, the driving mechanism includes a backplane assembly and a pulling handle connected to the backplane assembly. The driving wheel assembly includes a connecting shaft and a rotating shaft bearing box for restricting the movement of the connecting shaft. The driving wheel is arranged at the end of the connecting shaft. The pulling handle is connected to the connecting shaft. The backplane assembly can pull the pulling handle through rotation, and the pulling handle can pull the connecting shaft to rotate to drive the driving wheel to rotate.

[0007] In a preferred embodiment, the first excitation unit includes a cylinder for accommodating the first permanent magnet. A central shaft is disposed through the interior of the cylinder, and a transmission wheel engaged with the driving wheel is arranged at the end of the central shaft.

[0008] In a preferred embodiment, the contact surface between the first permanent magnet and the inner wall of the cylinder is formed as an arc surface.

[0009] In a preferred embodiment, shaft holes for passing through the central shaft are formed in the centers of the first permanent magnet and the second permanent magnet.

[0010] In a preferred embodiment, the magnetic flux leakage scanning device further includes a chassis, and the driving wheel assembly, the first excitation unit, and the second excitation unit are all mounted on the chassis.

[0011] In a preferred embodiment, the backplane assembly includes two backplanes arranged in parallel, a backplane connecting rod connected between the two backplanes, and an adjustable connecting rod with two ends respectively connected to the backplane connecting rod and the pulling handle. The bottom end of the backplane is rotatably connected to the chassis, and the backplane connecting rod pulls the pulling handle through the adjustable connecting rod.

[0012] In a preferred embodiment, the adjustable connecting rod is perpendicular to the backplane connecting rod.

[0013] In a preferred embodiment, the pulling handle includes a pulling handle connecting rod parallel to the backplane connecting rod and two connecting plates. The tops of the two connecting plates are rotatably connected to both ends of the pulling handle connecting rod, and the bottoms are fixedly connected to the connecting shaft.

[0014] In a preferred embodiment, the second excitation unit has the same structure as the first excitation unit, and the magnetic poles of the first permanent magnet and the second permanent magnet close to the magnetic bridge are opposite.

[0015] The present invention includes a driving wheel assembly, a driving mechanism for driving the rotation of the driving wheel of the driving wheel assembly, a first excitation unit and a second excitation unit meshing with the driving wheel, and a magnetic bridge. The first excitation unit and the second excitation unit respectively have a first permanent magnet and a second permanent magnet inside. The magnetic bridge can connect the magnetic poles of the first permanent magnet and the second permanent magnet into a loop, and the driving wheel drives the first excitation unit and the second excitation unit to rotate through rotation, so that the magnetic poles of the first permanent magnet and the second permanent magnet change the orientation relative to the magnetic bridge and the distance between the ends of the magnetic poles and the magnetic bridge, thereby being able to adjust the magnetization ability and magnetic suction force of the first excitation unit and the second excitation unit of the magnetic flux leakage scanning device, greatly improving the detection application range of the magnetic flux leakage scanning device, being able to output different magnetization abilities for storage tank bottom plates of different thicknesses, optimizing the magnetization degree of the storage tank bottom plate, and obtaining the best signal-to-noise ratio and detection sensitivity.

[0016] In addition, by adjusting the magnetization ability and magnetic suction force of the first excitation unit and the second excitation unit of the magnetic flux leakage scanning device, the attraction force of the magnetic flux leakage scanning device on the storage tank bottom plate can be reduced, which is convenient for the inspector to pry up and put down the magnetic flux leakage scanning device, improving the detection efficiency; it can also reduce the impact force of the first excitation unit and the second excitation unit of the magnetic flux leakage scanning device on the storage tank bottom plate, thereby reducing the risk of mechanical damage to the bottom plate; it can also reduce the risk of generating electric sparks, improving the safety factor during the detection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematically shows the overall structure of the magnetic flux leakage scanning device according to the present invention;

[0018] Figure 2 Schematically shows another overall structure of the magnetic flux leakage scanning device according to the present invention;

[0019] Figure 3 Schematically shows a structural schematic diagram of the first excitation unit of the magnetic flux leakage scanning device according to the present invention in a state where the transmission wheel is not installed;

[0020] Figure 4 Schematically shows a schematic diagram of the magnetic flux leakage scanning device according to the present invention in a state where the magnetic circuit is connected;

[0021] Figure 5 Schematically shown is a schematic diagram of the magnetic flux leakage scanning device according to the present invention in a magnetic circuit closed state.

[0022] In this application, all the drawings are schematic drawings, only for explaining the principle of the present invention and not drawn to actual scale. Detailed implementation manners

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0024] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "inner", "outer", "upper", "lower", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0025] It should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0026] In the present invention, unless otherwise clearly defined and limited, the terms "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Such as Figures 1 to 4As shown in the figure, the magnetic flux leakage scanning device 100 of the present invention includes: a driving wheel assembly, a driving mechanism for driving the driving wheel 1 of the driving wheel assembly to rotate, a first excitation unit 2 and a second excitation unit 3 engaged with the driving wheel 1, and a magnetic bridge 4. The magnetic bridge 4 is disposed obliquely above the first excitation unit 2 and the second excitation unit 3. Optionally, the magnetic bridge 4 is in contact with the side surfaces of the first excitation unit 2 and the second excitation unit 3. The first excitation unit 2 and the second excitation unit 3 respectively have a first permanent magnet 21 and a second permanent magnet 31 inside. The magnetic bridge 4 can connect the magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 into a loop. The driving wheel 1 drives the first excitation unit 2 and the second excitation unit 3 to rotate by rotation, so that the magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 change the orientation relative to the magnetic bridge 4 and the distance between the ends of the magnetic poles and the magnetic bridge, so as to adjust the magnetization ability and magnetic suction of the magnetic flux leakage scanning device 100. Optionally, the driving wheel 1 is disposed obliquely above the first excitation unit 2 and the second excitation unit 3, and the driving wheel 1 can drive the first excitation unit 2 and the second excitation unit 3 to rotate by rotation. Exemplarily, both the first permanent magnet 21 and the second permanent magnet 31 rotate counterclockwise.

[0028] The driving wheel 1 is driven to rotate by the driving mechanism, and the driving wheel 1 further drives the first excitation unit 2 and the second excitation unit 3 to rotate. The first permanent magnet 21 and the second permanent magnet 31 inside the first excitation unit 2 and the second excitation unit 3 respectively follow the first excitation unit 2 and the second excitation unit 3 to rotate, and can change the orientation of the magnetic poles of the two relative to the magnetic bridge 4 and the distance between the ends of the magnetic poles and the magnetic bridge 4. The magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 close to the magnetic bridge 4 are opposite. As Figure 4 shown, when the magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 face the magnetic bridge 4, the first permanent magnet 21, the second permanent magnet 31 and the magnetic bridge 4 can be connected into a magnetic circuit, so that the magnetic flux leakage scanning device 100 has magnetization ability and magnetic suction. The first excitation unit 2 and the second excitation unit 3 can magnetize the storage tank bottom plate below them together while performing detection. And when the first permanent magnet 21 and the second permanent magnet 31 rotate to face the magnetic bridge 4 and the magnetic pole ends of the two are closest to the magnetic bridge 4, the magnetic flux leakage scanning device 100 has the maximum magnetization ability and magnetic suction. As Figure 5 shown, when the first permanent magnet 21 and the second permanent magnet 31 rotate to the magnetic poles no longer facing the magnetic bridge 4, the first permanent magnet 21, the second permanent magnet 31 and the magnetic bridge 4 cannot be connected into a magnetic circuit, so that the magnetic flux leakage scanning device 100 does not have magnetization ability and magnetic suction.

[0029] It should be noted that the magnetic flux leakage scanning device 100 further includes a first horseshoe 5 and a second horseshoe 6. When the first permanent magnet 21 and the second permanent magnet 31 rotate until their magnetic poles no longer face the magnetic bridge 4, a magnetic circuit is formed by the first permanent magnet 21, the magnetic bridge 4, and the first horseshoe 5, and a magnetic circuit is formed by the second permanent magnet 31, the magnetic bridge 4, and the second horseshoe 6. When the magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 face the magnetic bridge 4, the first permanent magnet 21, the second permanent magnet 31, the magnetic bridge 4, the first horseshoe 5, and the second horseshoe 6 can be connected into a magnetic circuit. The upper surfaces of the first horseshoe 5 and the second horseshoe 6 both have arc-shaped portions, which are respectively used to contact the side surfaces of the first excitation unit 2 and the second excitation unit 3.

[0030] The present invention includes a driving wheel assembly, a driving mechanism for driving the driving wheel 1 of the driving wheel assembly to rotate, a first excitation unit 2 and a second excitation unit 3 meshing with the driving wheel 1, and a magnetic bridge 4. The first excitation unit 2 and the second excitation unit 3 respectively have a first permanent magnet 21 and a second permanent magnet 31 inside. The magnetic bridge 4 can connect the magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 into a loop, and the driving wheel 1 drives the first excitation unit 21 and the second excitation unit 31 to rotate by rotation, so that the magnetic poles of the first permanent magnet 21 and the second permanent magnet 31 change the orientation relative to the magnetic bridge 4 and the distance between the ends of the magnetic poles and the magnetic bridge 4. Thus, the magnetization ability and magnetic suction force of the first excitation unit 2 and the second excitation unit 3 of the magnetic flux leakage scanning device 100 can be adjusted, greatly improving the detection application range of the magnetic flux leakage scanning device 100. It can output different magnetization abilities for storage tank bottom plates of different thicknesses, optimize the magnetization degree of the storage tank bottom plate, and obtain the best signal-to-noise ratio and detection sensitivity.

[0031] In addition, by adjusting the magnetization ability and magnetic suction force of the first excitation unit 2 and the second excitation unit 3 of the magnetic flux leakage scanning device 100, the attraction of the magnetic flux leakage scanning device 100 to the storage tank bottom plate can be reduced, facilitating the inspector to pry up and put down the magnetic flux leakage scanning device 100 and improving the detection efficiency; it can also reduce the impact force of the first excitation unit 2 and the second excitation unit 3 of the magnetic flux leakage scanning device on the storage tank bottom plate, thereby reducing the risk of mechanical damage to the bottom plate; it can also reduce the risk of generating electric sparks and improve the safety factor during the detection process.

[0032] In one or more embodiments, the driving mechanism includes a back plate assembly and a pulling handle 91 connected to the back plate assembly. The driving wheel assembly includes a connecting shaft 5 and a rotating shaft bearing box 6 connected to the connecting shaft 5 and used to limit the movement of the connecting shaft 5. The driving wheel 1 is arranged at the end of the connecting shaft 5. The pulling handle 91 is connected to the connecting shaft 5. The back plate assembly can pull the pulling handle 91 by rotation, and the pulling handle 91 can pull the connecting shaft 5 to rotate to drive the driving wheel 1 to rotate.

[0033] In one or more embodiments, the first excitation unit 2 includes a cylinder 22 that houses a first permanent magnet 21. A central shaft 24 passes through the interior of the cylinder 22, and a transmission wheel 23 that meshes with the drive wheel 1 is provided at the end of the central shaft 24. The second excitation unit 3 has the same structure as the first excitation unit 2, and the poles of the first permanent magnet 21 and the second permanent magnet 31 that are close to the magnetic bridge 4 are opposite. It should be noted that drive wheels 1 are provided at both ends of the connecting shaft 5, and transmission wheels 23 that mesh with the drive wheels 1 are provided at both ends of the central shafts 24 of the first excitation unit 2 and the second excitation unit 3. Both the drive wheels 1 and the transmission wheels can be gears.

[0034] In one or more embodiments, the contact surface between the first permanent magnet 21 and the inner wall of the cylinder 22 is formed as an arc surface. Specifically, the main body of the first permanent magnet 21 is a columnar body, and spherical bodies are integrally formed at the upper end and the lower end of the main body respectively, and the two spherical bodies are in contact with the inner wall of the cylinder 22. The second permanent magnet 31 has the same structure as the first permanent magnet 21.

[0035] In one or more embodiments, a shaft hole for passing through the central shaft 24 is provided at the center of the first permanent magnet 21. Correspondingly, a shaft hole for passing through the central shaft 24 is also provided at the center of the second permanent magnet 31.

[0036] In one or more embodiments, the magnetic leakage scanning device 100 of the present invention further includes a chassis 6, and the drive wheel assembly, the first excitation unit 2, and the second excitation unit 3 are all installed on the chassis 6.

[0037] In one or more embodiments, the backplane assembly includes two backplanes 7 arranged in parallel, a backplane link 8 connected between the two backplanes 7, and an adjustable link 9 whose two ends are respectively connected to the backplane link 8 and the pulling handle 91. The bottom end of the backplane 7 is rotatably connected to the chassis 6. Specifically, the bottom end of the backplane 7 is hinged to the chassis 6, and the backplane link 8 pulls the pulling handle 91 through the adjustable link 9. By rotating the backplane 7, the backplane link 8 can pull the adjustable link 9, and the adjustable link can then pull the pulling handle 91. Optionally, the backplane link 8 is perpendicular to the two backplanes 7.

[0038] In one or more embodiments, the adjustable link 9 is perpendicular to the backplane link 8.

[0039] In one or more embodiments, the pulling handle 91 includes a pulling handle connecting rod 92 and two parallel connecting plates 93. The tops of the two connecting plates 93 are rotatably connected to the two ends of the pulling handle connecting rod 92, and the bottoms of the two connecting plates 93 are fixedly connected to the connecting shaft 5. The connecting plates 93 are perpendicularly arranged with respect to the pulling handle connecting rod 92.

[0040] In one or more embodiments, the adjustable connecting rod 9 includes a connecting rod body and a first connecting sleeve and a second connecting sleeve provided at both ends of the connecting rod body. Through holes are formed in both the first connecting sleeve and the second connecting sleeve. The backplane connecting rod 8 passes through the through hole formed in the first connecting sleeve, and the pulling handle connecting rod 92 passes through the through hole formed in the second connecting sleeve and is connected to the backplane connecting rod 8 through a shaft hole. The length of the adjustable connecting rod 9 can be adjusted by adjusting the length of the main body.

[0041] In one or more embodiments, the backplane assembly further includes a handle 94 vertically connected between the two backplanes. By providing the handle, it is convenient for the inspector to operate.

[0042] Although the present invention has been described with reference to the preferred embodiments, various improvements can be made to it and components therein can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A magnetic flux leakage scanning device, comprising: a magnetic bridge, a driving wheel assembly, a driving mechanism for driving the driving wheel of the driving wheel assembly to rotate, and a first excitation unit and a second excitation unit engaged with the driving wheel, wherein the first excitation unit and the second excitation unit respectively have a first permanent magnet and a second permanent magnet inside. The magnetic bridge can connect the magnetic poles of the first permanent magnet and the second permanent magnet into a loop. The driving wheel drives the first excitation unit and the second excitation unit to rotate through rotation, so that the orientation of the magnetic poles of the first permanent magnet and the second permanent magnet relative to the magnetic bridge and the distance between the ends of the magnetic poles from the magnetic bridge are changed.

2. The magnetic flux leakage scanning device according to claim 1, characterized in that the driving mechanism includes a backplane assembly and a pulling handle connected to the backplane assembly. The driving wheel assembly includes a connecting shaft and a rotating shaft bearing box for restricting the movement of the connecting shaft. The driving wheel is arranged at the end of the connecting shaft. The pulling handle is connected to the connecting shaft. The backplane assembly can pull the pulling handle through rotation, and the pulling handle can pull the connecting shaft to rotate to drive the driving wheel to rotate.

3. The magnetic flux leakage scanning device according to claim 2, characterized in that the first excitation unit includes a cylinder for accommodating the first permanent magnet. A central shaft is arranged inside the cylinder, and a transmission wheel engaged with the driving wheel is arranged at the end of the central shaft.

4. The magnetic flux leakage scanning device according to claim 3, characterized in that the contact surface between the first permanent magnet and the inner wall of the cylinder is made into an arc surface.

5. The magnetic flux leakage scanning device according to claim 3, characterized in that axial holes for passing through the central shaft are formed in the centers of the first permanent magnet and the second permanent magnet.

6. The magnetic flux leakage scanning device according to claim 2, characterized in that the magnetic flux leakage scanning device further includes a chassis, and the driving wheel assembly, the first excitation unit and the second excitation unit are all installed on the chassis.

7. The magnetic flux leakage scanning device according to claim 6, characterized in that the backplane assembly includes two backplanes arranged in parallel, a backplane connecting rod connected between the two backplanes, and an adjustable connecting rod with two ends respectively connected to the backplane connecting rod and the pulling handle. The bottom end of the backplane is rotatably connected to the chassis, and the backplane connecting rod pulls the pulling handle through the adjustable connecting rod.

8. The magnetic flux leakage scanning device according to claim 7, characterized in that the adjustable connecting rod is perpendicular to the backplane connecting rod.

9. The magnetic flux leakage scanning device according to claim 7, characterized in that the pulling handle includes a pulling handle connecting rod parallel to the backplane connecting rod and two connecting plates. The top ends of the two connecting plates are rotatably connected to both ends of the pulling handle connecting rod, and the bottom ends are fixedly connected to the connecting shaft.

10. The magnetic flux leakage scanning device according to claim 1, characterized in that the second excitation unit has the same structure as the first excitation unit, and the magnetic poles of the first permanent magnet and the second permanent magnet close to the magnetic bridge are opposite.

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