Large non-planar complex steel structure local residual magnetism special portable demagnetization device

Abstract

The utility model discloses a portable demagnetization device special for large -scale non -plane complex steel structure local residual magnetism belongs to steel structure demagnetization processing technical field. In the device, controllable power supply is used for producing attenuation alternating current, and the demagnetization coil is electrically connected with the controllable power supply through a cable. The demagnetizer comprises a shell and a demagnetization coil arranged in the shell. The wire diameter of the demagnetization coil is 1mm-1.5mm. The single-layer number of turns of the demagnetization coil is 49-55 turns. The layer number of the demagnetization coil is 32-38 layers. The inner diameter of the demagnetization coil is 20-40mm. The utility model realizes convenient operation, high demagnetization efficiency and can cope with complex working conditions such as narrow space, curved surface or internal cavity in large components.

Description

Technical Field

[0001] This utility model belongs to the field of steel structure demagnetization technology, and specifically relates to a portable demagnetization device for local residual magnetism in large non-planar complex steel structures. Background Technology

[0002] According to GB 50205 "Standard for Acceptance of Construction Quality of Steel Structures", large steel structures must be free of cracks at the acceptance level. Magnetic particle testing is one of the commonly used methods for detecting microcracks on the surface of large steel structures (GB / T15822.1-2024 "Nondestructive Testing - Magnetic Particle Testing Part 1: General Principles", GB / T 15822.2-2024 "Nondestructive Testing - Magnetic Particle Testing Part 2: Testing Media"). However, large steel structures are susceptible to residual magnetism due to natural aging, geomagnetism, and welding repairs. The presence of residual magnetism can affect the accuracy of magnetic particle defect detection, causing magnetic particles to abnormally accumulate in crack-free areas, forming "false crack" signals. To distinguish between true cracks and residual magnetic artifacts, additional demagnetization treatment is required for large steel structures.

[0003] A demagnetizer mainly consists of a demagnetizing coil that generates a decaying magnetic field and a controllable power supply box. The controllable power supply box adjusts the voltage (or current) value and direction to make the coil generate a decaying alternating magnetic field, so that the residual magnetism of the parts to be demagnetized around the coil is reduced to meet the requirements.

[0004] Existing demagnetizers can be broadly categorized based on the type of component being demagnetized: general-purpose demagnetizers for small and medium-sized components, and localized demagnetizers for flat areas on large components. However, for complex structures such as narrow spaces, curved surfaces, or internal cavities within large components, existing demagnetizers are too bulky and lack flexibility to penetrate these complex structures effectively. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. Therefore, one objective of this invention is to provide a portable demagnetizing device specifically designed for the localized residual magnetism of large, non-planar, complex steel structures. This device is easy to operate, has high demagnetizing efficiency, and is suitable for large, non-planar, complex steel structures.

[0006] According to an embodiment of this utility model, a portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures includes: A controllable power supply, wherein the controllable power supply is used to generate a damped alternating current; A demagnetizer, wherein the demagnetizing coil is electrically connected to the controllable power supply via a cable; the demagnetizer includes a housing and a demagnetizing coil disposed within the housing, wherein the wire diameter of the demagnetizing coil is 1mm-1.5mm, the number of turns in a single layer of the demagnetizing coil is 49-55, the number of layers of the demagnetizing coil is 32-38, and the inner diameter of the demagnetizing coil is 20-40mm.

[0007] The portable demagnetizing device for local residual magnetism in large non-planar complex steel structures provided by this utility model has the following advantages: it is lightweight and simple in structure and easy to operate; it can go deep into the narrow space, curved surface or internal cavity of large components for demagnetization; it can be directly integrated into the existing testing process; it can effectively eliminate residual magnetism interference, avoid testing misjudgment, and reduce the cost of repeated testing.

[0008] In some embodiments, the demagnetizing coil has a wire diameter of 1 mm, a single layer of the demagnetizing coil has 53 turns, the demagnetizing coil has 35 layers, and the inner diameter of the demagnetizing coil is 30 mm.

[0009] In some embodiments, the demagnetizer further includes a coil frame on which the demagnetizing coil is wound; The housing includes a first housing and a second housing. The first housing is cylindrical and has an open end and a closed end. A central mounting post is provided inside the first housing. One end of the central mounting post is fixed to the closed end. The coil frame is fitted onto the central mounting post. The second housing is disposed at the open end of the first housing and is detachably fixed to the first housing to encapsulate the coil frame and the demagnetizing coil inside the housing.

[0010] In some embodiments, the central mounting post is integrally formed with the first housing.

[0011] In some embodiments, the demagnetizer further includes a damping pad disposed between the end face of the housing and the end face of the coil frame.

[0012] In some embodiments, the demagnetizer further includes a handle, one end of which is fixed to the second housing.

[0013] In some embodiments, one end of the handle is provided with a flange, which is mated with the end of the second housing and fixed by a first bolt.

[0014] In some embodiments, the central mounting post has an extension that passes through the second housing, extends into the handle, and is secured to the handle.

[0015] In some embodiments, the handle includes two mating handle housings, the extension of the central mounting post is sandwiched between the two handles, and is secured by a second bolt passing through the two handle housings and the extension.

[0016] In some embodiments, the demagnetizer further includes a switch for controlling the connection and disconnection of the circuit between the controllable power supply and the demagnetizer.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a portable demagnetizing device for localized residual magnetism in large, non-planar, complex steel structures, according to this utility model. Figure 2 This is a cross-sectional schematic diagram of the portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures, which is a utility model. Figure 3 This is a schematic diagram of the structure of the portable demagnetizing device for local residual magnetism in large non-planar complex steel structures, which is a demagnetizer according to this utility model.

[0019] Figure Labels Portable demagnetizing device 1000 for large non-planar complex steel structures with local residual magnetism; controllable power supply 1; demagnetizer 2; demagnetizing coil 201; outer shell 202; first outer shell 2021; central mounting column 20211; extension 202111; second outer shell 2022; coil frame 203; shock-absorbing pad 204; handle 205; handle housing 2051; switch 206; first bolt 207; second bolt 208. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0021] The following is combined with Figures 1 to 3 This invention describes a portable demagnetizing device 1000 for the local residual magnetism of large non-planar complex steel structures, based on an embodiment of the present invention.

[0022] like Figures 1 to 3As shown, the portable demagnetizing device 1000 for local residual magnetism of large non-planar complex steel structures according to this utility model includes a controllable power supply 1 and a demagnetizer 2.

[0023] Among them, the controllable power supply 1 is used to generate a decaying alternating current; the controllable power supply 1 converts the incoming 220V 50Hz AC power into a controlled decaying alternating current and outputs it.

[0024] The demagnetizing coil 201 is electrically connected to the controllable power supply 1 via a cable. The demagnetizer 2 includes a housing 202 and the demagnetizing coil 201 disposed within the housing 202. The housing 202 provides support and protection for the demagnetizing coil 201 and also serves as insulation. The demagnetizing coil 201 has a wire diameter of 1mm-1.5mm, 49-55 turns per layer, 32-38 layers, and an inner diameter of 20-40mm. The main function of the demagnetizing coil 201 is to generate a decaying alternating magnetic field using a decaying alternating current; it is the core component of the demagnetizing device. The above-mentioned structural parameters of the demagnetizing coil 201 were obtained in the following way: based on the remanence of the steel structure, the required structure of the demagnetizing coil 201 was calculated and optimized using COMSOL electromagnetic finite element simulation software, so that it can generate a magnetic field with a field strength that meets the demagnetization requirements under safe current conditions. The size of the demagnetizing coil 201 was optimized by orthogonal iteration of the number of coil layers and the number of turns per layer, so that the overall size of the demagnetizing coil 201 structure is as small as possible.

[0025] The demagnetizing coil 201 minimizes its size while ensuring electrical safety and the required demagnetizing magnetic field strength. Combined with the demagnetizer's structural design, it makes the demagnetizer structure more compact. It can achieve local demagnetization in complex shapes such as narrow spaces, curved surfaces, or internal cavities in large components. It can effectively eliminate residual magnetism caused by welding heat, thereby avoiding residual magnetism artifacts in the magnetic particle nondestructive testing process for cracks. This reduces misjudgments of whether a structure contains cracks and avoids waste of manpower and resources.

[0026] The portable demagnetizing device 1000 for localized residual magnetism in large, non-planar complex steel structures provided by this utility model has the following advantages: it is lightweight and simple in structure, and easy to operate; it can penetrate deep into narrow spaces, curved surfaces, or internal cavities of large components for demagnetization; it can be directly integrated into existing testing processes; it can effectively eliminate residual magnetism interference, avoid misjudgment, and reduce the cost of repeated testing. The portable demagnetizing device 1000 for localized residual magnetism in large, non-planar complex steel structures provided by this utility model is suitable for demagnetizing large, non-planar complex steel structures.

[0027] In some embodiments, the demagnetizing coil 201 has a wire diameter of 1 mm, a single layer of 53 turns, 35 layers, and an inner diameter of 30 mm. This demagnetizing coil 201 minimizes the overall size while ensuring electrical safety and the required demagnetizing magnetic field strength. Therefore, it results in a smaller overall size of the demagnetizer, more flexible operation, and suitability for demagnetizing large, non-planar, complex steel structures.

[0028] In some embodiments, the demagnetizer 2 further includes a coil frame 203 on which a demagnetizing coil 201 is wound. The coil frame 203 facilitates the winding of the demagnetizing coil 201 and also makes it easy to fix the demagnetizing coil 201 inside the housing 202.

[0029] The outer casing 202 includes a first outer casing 2021 and a second outer casing 2022. The first outer casing 2021 is cylindrical and has an open end and a closed end. A central mounting post 20211 is provided inside the first outer casing 2021, with one end of the central mounting post 20211 fixed to the closed end. The coil frame 203 is fitted onto the central mounting post 20211. The second outer casing 2022 is disposed at the open end of the first outer casing 2021 and is detachably fixed to the first outer casing 2021 to encapsulate the coil frame 203 and the demagnetizing coil 201 within the outer casing 202. The outer casing 202 provides support, protection, and installation space for the demagnetizing coil 201. The central mounting post 20211 fixes the coil frame 203, facilitating installation and effectively preventing the demagnetizing coil 201 from shifting during operational vibration, thus ensuring the stability of the magnetic field.

[0030] In some embodiments, the central mounting post 20211 is integrally formed with the first housing 2021, reducing the assembly process between the central mounting post 20211 and the first housing 2021.

[0031] In some embodiments, the demagnetizer 2 further includes a damping pad 204, which is disposed between the end face of the housing 202 and the end face of the coil frame 203. Since vibrations will occur during the demagnetization process, the damping pad 204 is used to buffer and absorb vibrations to avoid damage to the structure of the demagnetizing coil 201.

[0032] In some embodiments, the demagnetizer 2 further includes a handle 205, one end of which is fixed to the second housing 2022. The operator holds the handle 205 to complete the demagnetization operation, which is portable and operable.

[0033] In some embodiments, one end of the handle 205 is provided with a flange, which is mated with the end of the second housing 2022 and fixed by a first bolt 207. In this way, a high-strength and highly reliable detachable connection can be achieved between the handle 205 and the main body of the demagnetizer 2.

[0034] In some embodiments, the central mounting post 20211 has an extension 202111 that passes through the second housing 2022, extends into the handle 205, and is fixed to the handle 205. This results in a stronger and more reliable connection between the handle 205 and the housing 202.

[0035] In some embodiments, the handle 205 includes two mating handle housings 2051, with an extension 202111 of the central mounting post 20211 sandwiched between the two handles 205 and secured by a second bolt 208 passing through the two handle housings 2051 and the extension 202111. The mating design makes the handle housings 2051 easy to manufacture and assemble, and facilitates the internal cable layout.

[0036] In some embodiments, the demagnetizer 2 further includes a switch 206, which controls the connection and disconnection of the circuit between the controllable power supply 1 and the demagnetizer 2. The switch 206 is connected to a signal power supply and can output a control signal to control the connection and disconnection of the circuit between the controllable power supply 1 and the demagnetizer 2. The circuit of switch 206 on the handle 205, which is directly contacted by the operator, operates at a safe voltage. Even if the insulation of switch 206 or the signal line is damaged, it will not pose any risk of electric shock to the operator, thus increasing safety during use.

[0037] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A portable demagnetizing device specifically designed for localized residual magnetism in large, non-planar, complex steel structures, characterized in that: include: A controllable power supply, wherein the controllable power supply is used to generate a damped alternating current; A demagnetizer, wherein the demagnetizing coil is electrically connected to the controllable power supply via a cable; the demagnetizer includes a housing and a demagnetizing coil disposed within the housing, wherein the wire diameter of the demagnetizing coil is 1mm-1.5mm, the number of turns in a single layer of the demagnetizing coil is 49-55, the number of layers of the demagnetizing coil is 32-38, and the inner diameter of the demagnetizing coil is 20-40mm.

2. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 1, characterized in that, The demagnetizing coil has a wire diameter of 1mm, a single layer of the demagnetizing coil has 53 turns, the demagnetizing coil has 35 layers, and the inner diameter of the demagnetizing coil is 30mm.

3. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 1, characterized in that, The demagnetizer also includes a coil frame on which the demagnetizing coil is wound. The housing includes a first housing and a second housing. The first housing is cylindrical and has an open end and a closed end. A central mounting post is provided inside the first housing. One end of the central mounting post is fixed to the closed end. The coil frame is fitted onto the central mounting post. The second housing is disposed at the open end of the first housing and is detachably fixed to the first housing to encapsulate the coil frame and the demagnetizing coil inside the housing.

4. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 3, characterized in that, The central mounting post is integrally formed with the first outer shell.

5. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 3, characterized in that, The demagnetizer also includes a shock-absorbing pad, which is disposed between the end face of the housing and the end face of the coil frame.

6. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 5, characterized in that, The demagnetizer also includes a handle, one end of which is fixed to the second housing.

7. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 6, characterized in that, One end of the handle is provided with a flange, which is mated with the end of the second housing and fixed by a first bolt.

8. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 6, characterized in that, The central mounting post has an extension that passes through the second housing, extends into the handle, and is fixed to the handle.

9. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 8, characterized in that, The handle includes two mating handle housings, and the extension of the central mounting post is sandwiched between the two handles and fixed by a second bolt passing through the two handle housings and the extension.

10. The portable demagnetizing device for localized residual magnetism in large non-planar complex steel structures according to claim 1, characterized in that, The demagnetizer also includes a switch for controlling the connection and disconnection of the circuit between the controllable power supply and the demagnetizer.

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