Magnetic flux leakage internal inspection device for pipelines

Abstract

The utility model discloses a kind of magnetic flux leakage internal detection devices for pipeline. Including: mounting rack;Magnet assembly, at least part of mounting rack is sleeved, magnet assembly includes first magnet group and second magnet group;Transmission execution component, it is set to the side of first magnet group away from second magnet group, transmission execution component is configured as cleaning pipeline inner wall;Detection component, it is set between first magnet group and second magnet group, detection component is configured to receive the magnetic field change of magnet assembly. Through the position setting of detection component and magnet assembly, the accuracy of detection data is improved;Through the modularization setting of each component, the detachability of internal detection device is improved, and it is convenient to overhaul maintenance and replacement.

Description

Technical Field

[0001] This utility model relates to the field of pipeline inspection technology, and in particular to an internal magnetic flux leakage detection device for pipelines. Background Technology

[0002] In the pipeline transportation field, magnetic flux leakage (MF) testing is a crucial means of ensuring the safe operation of pipelines. Its principle lies in utilizing the property that ferromagnetic materials, when magnetized, generate a magnetic leakage field at defects. By detecting this leakage field, pipeline defects such as corrosion and cracks can be identified. This technology is widely used in the inspection of various transportation pipelines, including oil and gas pipelines and water pipelines. It can effectively assess the internal condition of pipelines without damaging their structure, promptly identifying potential safety hazards and providing crucial information for pipeline maintenance and repair.

[0003] In related technologies, during pipeline inspection, uneven pipeline material and inherent errors in the inspection device can lead to abnormal inspection data, making it impossible to accurately identify pipeline defects and causing misjudgments; or the device structure may be complex and inconvenient to disassemble and repair. Utility Model Content

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0005] In view of this, the present invention provides an internal magnetic flux leakage detection device for pipelines, wherein the accuracy of detection data is improved by the positional arrangement of the detection component and the magnet component; and the modular arrangement of each component improves the disassembly of the internal detection device, facilitating inspection, maintenance and replacement.

[0006] Specifically, the following technical solutions are included: This utility model provides an internal magnetic flux leakage detection device for pipelines, the internal detection device comprising: Install rack; A magnet assembly, fitted onto at least a portion of the mounting frame, the magnet assembly comprising a first magnet group and a second magnet group; A transmission actuator is disposed on the side of the first magnet group opposite to the second magnet group, and the transmission actuator is configured to clean the inner wall of the pipe; A detection component is disposed between the first magnet group and the second magnet group, and the detection component is configured to receive changes in the magnetic field of the magnet group.

[0007] Optionally, the mounting frame includes a first support and a second support connected to each other, the second support passing through the magnet assembly and the detection assembly.

[0008] Optionally, the first support member includes: a pair of support plates, a universal joint between the pair of support plates, both ends of the universal joint passing through the pair of support plates respectively, and the universal joint being fixedly connected to the support plates. Fixed steering shafts are provided on both ends of the universal joint, and the fixed steering shafts extend in a direction away from the support plates.

[0009] Optionally, the first magnet assembly includes an annular N-pole permanent magnet block, the second magnet assembly includes an S-pole permanent magnet block and a permanent magnet block, the permanent magnet block being disposed on the side of the S-pole permanent magnet block away from the N-pole permanent magnet block, and the detection assembly being disposed between the S-pole permanent magnet block and the N-pole permanent magnet block.

[0010] Optionally, the magnet assembly further includes: A magnetic guide ring is disposed on both sides of the N-pole permanent magnet block and on both sides of the S-pole permanent magnet block.

[0011] Optionally, the magnetic ring includes: The ring body is fitted onto the mounting frame, and the ring body forms a receiving space; A cover is provided on both sides of the ring body in the axial direction, and the cover is configured to close the receiving space; A magnetically conductive arc plate is disposed within the accommodating space. Multiple magnetically conductive heads are evenly disposed on the magnetically conductive arc plate. The magnetically conductive heads are located on both sides of the magnetically conductive arc plate and extend toward the sealing direction.

[0012] Optionally, the transmission actuation component includes: A rocker arm bracket is disposed on the side of the first magnet group away from the second magnet group, and the rocker arm bracket is fixedly connected to the mounting frame; The rotating rocker arm is rotatably connected to the rocker arm bracket. An iron brush is disposed at one end of the rotating rocker arm away from the rocker arm support. The iron brush includes a support rod and bristles spirally wound on the support rod.

[0013] Optionally, a plurality of springs are provided between the support rod and the rotating rocker arm.

[0014] Optionally, the detection component includes: A housing is fitted onto the mounting frame. Multiple magnetoresistive sensors are evenly arranged on the outer periphery of the housing. The housing has internal teeth on the side facing the mounting frame. A drive motor is located between the second magnet assembly and the housing. The output shaft of the drive motor is provided with a first gear and a second gear, and the first gear meshes with the internal gear. The third gear meshes with the second gear, and the third gear is fixedly connected to the transmission actuation component.

[0015] Optionally, the detection component and the magnet component are fixedly connected by a clamp assembly, the clamp assembly comprising: A first push rod is disposed on the detection assembly, and the first push rod has a first mounting slope and a first snap-fit ​​surface on some of its face toward the magnet assembly; The second push rod is hinged to the mounting shell of the magnet assembly. The second push rod has a second mounting slope and a second snap-fit ​​surface on the side facing the first push rod. The second mounting slope matches the first mounting slope. The first push rod and the second push rod are snap-fitted together through the first snap-fit ​​surface and the second snap-fit ​​surface. An abutment plate is fixedly connected to the mounting shell, and the end of the second push rod away from the detection component abuts against the abutment plate.

[0016] This utility model provides an internal magnetic flux leakage detection device for pipelines. The internal detection device includes a mounting frame, a magnet assembly, a transmission actuator, and a detection assembly. The mounting frame supports the entire internal detection device and allows for precise positioning of the magnet assembly, transmission actuator, and detection assembly, ensuring reliable detection. The magnet assembly and detection assembly work together. The magnet assembly uses a strong magnet to magnetize the pipeline wall. If the pipeline is free of defects, magnetic lines of force will pass evenly through the pipe wall. If defects exist (such as corrosion or holes), the magnetic permeability at that location will change, causing some magnetic lines of force to leak into the surrounding air. By detecting these leaked magnetic fields, the location and size of pipeline defects can be deduced. The transmission actuator cleans the inner wall of the pipeline and moves the internal detection device. The positioning and structure of the magnet assembly and detection assembly improve the reliability and stability of the internal detection device, reduce the influence of other factors, and improve the accuracy of the detection data.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of an internal detection device according to an embodiment of the present invention; Figure 2a This is a schematic diagram of a magnetic ring according to an embodiment of the present invention; Figure 2b This is a top view of a magnetic ring according to an embodiment of the present invention; Figure 3a This is a front view of a detection component according to an embodiment of the present invention; Figure 3b This is a side view of a detection component according to an embodiment of the present invention; Figure 4 This is a schematic diagram of a clamp assembly according to an embodiment of the present invention.

[0020] in, Figures 1 to 4 The correspondence between the reference numerals and component names in the attached drawings is as follows: 100 Internal detection device, 110 Mounting frame, 111 Support plate, 112 Fixed steering shaft, 113 Universal joint, 120 Magnet assembly, 121 Permanent magnet block, 122 S-pole permanent magnet block, 123 N-pole permanent magnet block, 124 Magnetic guide ring, 1241 Ring body, 1242 Magnetic guide arc plate, 1243 Magnetic guide head, 1244 Accommodation space, 130 Transmission actuation assembly, 131 Rotary rocker arm, 132 Iron brush, 140 Detection components: 141 Housing, 142 Internal gear, 143 Drive motor, 144 First gear, 145 Second gear, 146 Third gear, 147 Magnetoresistive sensor, 150 Clamp assembly, 151 First push rod, 1511 First mounting ramp, 1512 First snap-fit ​​surface, 152 Second push rod, 1521 Second mounting ramp, 1522 Second snap-fit ​​surface, 153 Abutment plate, 154 Pin, 155 Bearing. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0022] Before providing a further detailed description of the embodiments of this utility model, the directional terms used in the embodiments of this utility model, such as "upper part", "lower part" and "side part", do not have the meaning of limiting the scope of protection of this utility model.

[0023] To make the technical solution and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of an internal detection device according to an embodiment of the present invention.

[0025] like Figure 1 As shown, one embodiment of the present invention provides an internal magnetic flux leakage detection device 100 for pipelines, the internal detection device 100 comprising: Mounting rack 110; Magnet assembly 120 is fitted onto at least a portion of mounting frame 110, and magnet assembly 120 includes a first magnet group and a second magnet group; The transmission actuation component 130 is disposed on the side of the first magnet group away from the second magnet group, and the transmission actuation component 130 is configured to clean the inner wall of the pipe. The detection component 140 is disposed between the first magnet group and the second magnet group, and the detection component 140 is configured to receive the magnetic field changes of the magnet component 120.

[0026] The internal inspection device includes a mounting frame 110, a magnet assembly 120, a transmission actuator 130, and a detection assembly 140. The mounting frame 110 serves as the support for the entire internal inspection device 100, enabling the precise positioning of the magnet assembly 120, transmission actuator 130, and detection assembly 140 to ensure reliable inspection. The magnet assembly 120 and detection assembly 140 work together. The magnet in the magnet assembly 120 magnetizes the pipe wall. If the pipe is free of defects, magnetic lines of force will pass evenly through the pipe wall. If defects exist (such as corrosion or holes), the magnetic permeability at that location will change, causing some magnetic lines of force to leak into the surrounding air. By detecting these leaked magnetic fields through the detection assembly 140, the location and size of the pipe defects can be deduced. The transmission actuator 130 enables the cleaning of the pipe's inner wall and the movement of the internal inspection device 100. By adjusting the positions and structures of the magnet assembly 120 and the detection assembly 140, the reliability and stability of the internal detection device 100 can be improved, the degree of influence from other factors can be reduced, and the accuracy of the detection data can be increased.

[0027] It should be noted that the mounting frame 110 is made of high-strength, lightweight alloy material and undergoes special forging and heat treatment processes, giving it an extremely high strength-to-weight ratio. This allows the mounting frame 110 to withstand various stresses experienced by the internal detection device 100 during operation within the pipeline, including fluid impact and friction with the pipeline wall. Furthermore, it reduces the overall weight of the internal detection device 100, thereby reducing the load on the transmission actuator 130. In this embodiment, the mounting frame 110 is made of 6-series aluminum alloy, specifically grade 6061 aluminum alloy.

[0028] It is understandable that the components in this application are modularly designed, with a simple structure that facilitates individual replacement and disassembly.

[0029] In one possible implementation, the mounting frame 110 includes a first support and a second support that are interconnected, with the second support passing through the magnet assembly 120 and the detection assembly 140.

[0030] The first support component includes: a pair of support plates 111, a universal joint 113 between the pair of support plates 111, both ends of the universal joint 113 passing through the pair of support plates 111 respectively, and the universal joint 113 being fixedly connected to the support plates 111. Fixed steering shafts 112 are provided on both ends of the universal joint 113, and the fixed steering shafts 112 extend in a direction away from the support plates 111.

[0031] It should be noted that, as Figure 1 As can be seen, the exterior of the internal detection device 100 is streamlined, meaning that except for the permanent magnet block 121, everything else uses rounded transitions. This reduces the resistance of the internal detection device 100 in the fluid within the pipe, allowing it to move more smoothly and with reduced resistance. It is understood that the second support member is a stepped shaft, on which the magnet assembly 120 and the detection assembly 140 are mounted. The stepped shaft effectively supports magnet assemblies 120 and 140 with different inner diameters, allowing them to be accurately installed in their designed positions, thus improving the structural stability and assembly accuracy of the internal detection device 100.

[0032] For example, the fixed steering shaft 112 undergoes wear-resistant treatment, with a high-performance wear-resistant coating applied to its surface. This effectively reduces friction and wear against the inner wall of the pipe during operation, extending the service life of the fixed steering shaft. Specifically, the coating is treated with a ceramic coating using plasma spraying of an alumina-titanium oxide composite ceramic coating (Al2O3-TiO2, with a mass ratio of 8:2). First, a nitriding treatment is performed on the fixed steering shaft 112 to form a nitrided layer. Then, ceramic powder is melted and sprayed onto the surface of the nitrided layer using a plasma jet (velocity > 600 m / s). The coating thickness is controlled between 50 μm and 80 μm, with a surface roughness Ra ≤ 0.8 μm, porosity < 3%, coating hardness between 1200 HV and 1500 HV, and a bonding strength with the nitrided layer ≥ 30 MPa, with no risk of peeling.

[0033] In one feasible implementation, the first magnet assembly 120 includes an annular N-pole permanent magnet block 123, the second magnet assembly 120 includes an S-pole permanent magnet block 122 and a permanent magnet block 121, the permanent magnet block 121 is disposed on the side of the S-pole permanent magnet block 122 away from the N-pole permanent magnet block 123, and the detection assembly 140 is disposed between the S-pole permanent magnet block 122 and the N-pole permanent magnet block 123.

[0034] Through electromagnetic simulation and optimized design, the permanent magnet block 121 and the S-pole permanent magnet block 122 are configured as the second magnet assembly 120, while the N-pole permanent magnet block 123 forms the first magnet assembly 120. A detection assembly 140 is positioned between the second and first magnet assemblies. This configuration enables the superposition of magnetic fields, thereby enhancing the magnetic field and improving the stability and reliability of the detection signal from the detection assembly 140. This combination allows for the formation of a higher magnetic field in the target area using fewer and smaller permanent magnet blocks 121, while also achieving a uniform and flat magnetic field region, thus improving the reliability and stability of the magnetic (electrical) signal detected by the detection assembly 140.

[0035] It should be noted that the permanent magnet block 121 is in the shape of a regular polygonal prism, and in this embodiment it is in the shape of a regular hexagonal prism. On the one hand, this can further improve the uniformity and strength of the magnetic field, and on the other hand, it can reduce the waste of raw materials.

[0036] For example, the N-pole permanent magnet block 123, the S-pole permanent magnet block 122 and the permanent magnet block 121 are made of rare earth permanent magnet materials, which have the characteristics of high remanence and high coercivity, and can form a strong and stable magnetic field, thereby improving the stability and reliability of magnetic flux leakage detection.

[0037] In one possible implementation, the magnet assembly 120 further includes: Magnetic ring 124 is disposed on both sides of N-pole permanent magnet block 123 and on both sides of S-pole permanent magnet block 122.

[0038] Among them, magnetic rings 124 are provided between the permanent magnet block 121 and the S-pole permanent magnet block 122, on the side of the S-pole permanent magnet block 122 facing the N-pole permanent magnet block 123, on the side of the N-pole permanent magnet block 123 facing the S-pole permanent magnet block 122, and on the side of the N-pole permanent magnet block 123 away from the S-pole permanent magnet block 122. The magnetic rings 124 are sealed by a streamlined (arc transition) sealing plate. The S-pole permanent magnet block 122, the N-pole permanent magnet block 123 and the magnetic rings 124 are fitted together.

[0039] It should be noted that the permanent magnet 121, the S-pole permanent magnet 122, and the N-pole permanent magnet 123, together with the magnetic ring 124, form a highly efficient magnetic circuit. The magnetic field lines generated by these three magnets originate from the N-pole and return to the S-pole. Without the magnetic ring 124, these magnetic field lines would randomly close through the air, increasing the magnetic reluctance on the air side and causing the magnetic field strength to decay rapidly and become ineffective. By using the magnetic ring 124, a low-resistance shortcut path is provided for the magnetic field lines. The magnetic ring 124 captures most of the magnetic field lines emitted by the permanent magnets 121, S-pole, and N-pole, guiding them to flow along the ring and ultimately forming a closed, highly efficient magnetic loop. This reduces magnetic field leakage and waste. The cooperation between the magnetic guide ring 124 and the permanent magnet blocks 121, S-pole permanent magnet block 122, and N-pole permanent magnet block 123 can improve the magnetic field efficiency and intensity, and provide a uniform magnetic field space. In this embodiment, the magnetic guide ring 124 is made of a soft magnetic material with high magnetic permeability. That is to say, the cooperation of the magnetic guide ring 124 can effectively guide and constrain the distribution of magnetic field lines, making the magnetization of the inner wall of the pipe more uniform, thereby improving the sensitivity and accuracy of leakage magnetic field detection.

[0040] For example, to prevent demagnetization of permanent magnet 121, S-pole permanent magnet 122, and N-pole permanent magnet 123 during long-term use, a layer of material with good magnetic shielding performance can be placed on their exterior. This effectively isolates interference from external magnetic fields and ensures stable and reliable magnetic field performance of the magnet assembly 120. The shielding material can be silicon steel, a ferromagnetic material with high magnetic permeability. It is bonded to the surface of the shielding component in a thin sheet. Since the permeability of the shielding layer supported by the ferromagnetic material is thousands of times greater than that of air, most of the magnetic field lines of the external magnetic field pass along the inner wall of the ferromagnetic material, resulting in very little magnetic flux entering the interior, thus achieving the purpose of shielding against external magnetic fields. For static magnetic shielding, selecting materials with appropriate permeability and thickness can effectively shield against external magnetic fields while ensuring a stable internal magnetic field environment and preventing interference with the normal magnetic circuit inside the equipment.

[0041] Understandably, the magnet assembly 120 adopts an axially connected and radially symmetrical layout, located in the middle section of the inner detection device 100, forming a magnetic field detection area along the axis of the inner detection device 100. The permanent magnet block 121 serves as the base of the overall magnetic circuit, is a regular hexagonal prism with an outer circle diameter of 30mm and a length of 80mm, and uses neodymium iron boron permanent magnet material (grade N35), with a nickel-plated surface for rust prevention. The S-pole permanent magnet block 122 and the N-pole permanent magnet block 123 are arranged along the axial direction of the permanent magnet block 121, with an axial distance of 15mm between them, and the distance error is controlled within ±0.5mm. The S-pole permanent magnet block 122 and the N-pole permanent magnet block 123 have a thickness of 8mm (radial thickness) and a width of 25mm (axial length), and a gap of 2mm to 3mm is provided between them and the second support member to avoid magnetic interference with the second support member.

[0042] Figure 2a This is a schematic diagram of a magnetic ring according to an embodiment of the present invention; Figure 2b This is a top view of a magnetic ring according to an embodiment of the present invention.

[0043] In one feasible implementation, such as Figure 2a and Figure 2b As shown, the magnetic ring 124 includes: The ring body 1241 is fitted onto the mounting frame 110, and the ring body 1241 forms a receiving space 1244. The caps are located on both sides of the ring body 1241 in the axial direction and are configured in the enclosed receiving space 1244. A magnetic arc plate 1242 is disposed within the accommodating space 1244. Multiple magnetic heads 1243 are evenly disposed on the magnetic arc plate. The magnetic heads 1243 are located on both sides of the magnetic arc plate 1242 and extend towards the sealing direction.

[0044] The ring body 1241 and the cap form a receiving space 1244, constructing a completely closed magnetic circuit. The magnetic field is confined within the ring, with no external leakage, effectively shielding it from external interference. It also provides a stable magnetic field environment for the internal magnetic arc plate 1242 and magnetic head 1243. Under the influence of the magnetic field, the magnetic arc plate 1242 can carry the magnetic head 1243 to rotate slightly and uniformly within the receiving space 1244. The magnetic head 1243 transmits the magnetic signal (electrical signal) to the detection component 140. When a defect occurs in the pipeline (corrosion or cracks), the originally uniform magnetic signal will change and be captured by the detection device.

[0045] It should be noted that the magnetic arc plate 1242 focuses the radial magnetic field of the S-pole permanent magnet block 122 and the N-pole permanent magnet block 123 toward the inner wall of the pipe, thereby increasing the magnetic field strength at the inner wall of the pipe by 200mT to 250mT (compared to only 120mT to 150mT without the magnetic ring 124), enhancing the disturbance effect of pipe defects on the magnetic field. When the pipe has defects such as corrosion or cracks, the change in magnetic permeability at the defect location will cause magnetic field distortion. The magnetic head 1243 gathers the distorted magnetic field and conducts it to the detection component 140 (magnetoresistive sensor 147), amplifying the distorted signal (increasing the signal strength by more than 30%), making it easier for the detection component 140 to accurately capture it.

[0046] In one feasible implementation, the transmission actuation component 130 includes: A rocker arm bracket is located on the side of the first magnet group away from the second magnet group, and the rocker arm bracket is fixedly connected to the mounting frame 110. Rotary rocker arm 131 is rotatably connected to rocker arm bracket; A steel brush 132 is located at the end of the rotating rocker arm 131 away from the rocker arm support. The steel brush 132 includes a support rod and bristles spirally wound on the support rod.

[0047] The rocker arm bracket is fixedly connected to the end of the second support member away from the first support member. The rotating rocker arm 131 is connected to the rocker arm bracket via a bearing. The rotating rocker arm 131 is fixedly connected to the third gear 146. The rotation of the third gear 146 drives the rotation of the rotating rocker arm 131. The second support member and / or the rocker arm bracket provides a clearance for the third gear 146 to facilitate the rotation of the rotating rocker arm 131 driven by the third gear 146. The rotating rocker arm 131 and the rocker arm bracket are rotatably connected via a bearing, which can be a joint bearing, and sealed with a seal to ensure the stability and reliability of the rotating rocker arm 131 during movement, while preventing dust, moisture, and other impurities from entering the joint and affecting its movement performance. It is understood that the rotation diameter of the rotating rocker arm 131 is larger than the outer diameter of the magnet assembly 120 and the detection assembly 140. The movement of the internal detection device 100 within the pipe can be achieved through the engagement of the spiral bristles on the iron brush 132 with the inner wall threads (generated during cleaning).

[0048] Understandably, the spiral bristles, while cleaning the inner wall of the pipe, also remove debris and dust from the pipe's sidewalls, creating a spiral pattern. Subsequent spiral bristles then engage with this spiral sidewall, driving the movement of the internal detection device 100. The bristles can be made of wear-resistant composite materials, possessing high hardness, high toughness, and good self-lubricating properties, ensuring no damage to the inner wall during cleaning. Understandably, the rotation diameter of the bristles is larger than the diameters of the N-pole permanent magnet 123 and the S-pole permanent magnet 122. This prevents the detection component 140, the N-pole permanent magnet 123, and the S-pole permanent magnet 122 from contacting the inner wall of the pipe, minimizing wear on these components and improving the reliability of the internal detection device 100.

[0049] It should be noted that at the bend in the pipe, the spiral bristles first accumulate in a thread-like pattern on one side, while the other side is suspended. This results in more threads on the smaller bend side of the pipe's inner wall and fewer threads on the larger bend side. In this way, the spiral bristles drive the internal detection device 100 to turn within the pipe. Simultaneously, by setting a universal joint 113 between a pair of support plates 111 and a fixed steering shaft 112 on the side of the universal joint facing away from the support plates 111, the transmission actuator 130, being smaller than the overall volume of the subsequent mounting frame 110 and magnet assembly 120, allows the mounting frame 110 and magnet assembly 120 to cooperate with the turning force through the universal joint 113 and fixed steering shaft 112. This enables the internal detection device 100 to better navigate the bend in the pipe, meaning the universal joint 113 receives the rotational force, which then drives the entire mounting frame 110 to turn.

[0050] In one feasible implementation, a plurality of springs are provided between the support rod and the rotating rocker arm 131.

[0051] The connection between the iron brush 132 and the rotating rocker arm 131, i.e., the connection between the support rod and the rotating rocker arm 131, is achieved through a spring. This spring adjusts the pressure when the iron brush 132 contacts the inner wall of the pipe, preventing damage to the pipe or the iron brush 132 from hard contact. It also provides some shock absorption, improving the stability and reliability of the spiral brush bristles driving the internal detection device 100. As the iron brush 132 rotates with the rotating rocker arm 131, the brush bristles scrape and rub, removing rust, impurities, and oil contaminants adhering to the inner wall of the pipe. This prevents contaminants from interfering with the signal acquisition of the subsequent magnetoresistive sensor 147, improving the accuracy of the detection data from the internal detection device 100.

[0052] Figure 3a This is a front view of a detection component according to an embodiment of the present invention; Figure 3b This is a side view of a detection component according to an embodiment of the present invention.

[0053] In one feasible implementation, such as Figure 3a and Figure 3b As shown, the detection component 140 includes: The housing 141 is fitted onto the mounting frame 110. Multiple magnetoresistive sensors 147 are evenly arranged on the outer periphery of the housing 141. The housing 141 has internal teeth 142 on the side facing the mounting frame 110. A drive motor 143 is located between the second magnet group and the housing 141. The output shaft of the drive motor 143 is provided with a first gear 144 and a second gear 145. The first gear 144 meshes with the internal gear 142. The third gear 146 meshes with the second gear 145, and the third gear 146 is fixedly connected to the transmission actuation assembly 130.

[0054] A drive motor 143 is installed within the space formed by the housing 141 and the second support member. A first gear 144 and a second gear 145 are mounted on the output shaft of the drive motor 143. The first gear 144 meshes with the internal gear 142 of the housing 141. The rotation of the motor drives the magnetoresistive sensor 147 on the housing 141. Simultaneously, the second gear 145 meshes with a third gear. The drive motor 143 drives the second gear 145 to rotate, which in turn drives the third gear 146 to rotate. The third gear 146 is connected to the rotating rocker arm 131, thus achieving the purpose of one motor driving the detection component 140 and the transmission execution component 130 to rotate. It is understood that the first gear 144 has fewer teeth than the second gear 145 (and the third gear 146), meaning that the rotation of the detection component 140 is slower than the rotation of the rotating rocker arm 131. This allows the detection component 140 to better capture magnetic signals, and the rapid rotation of the brush 132 facilitates the overall movement of the internal detection device 100.

[0055] It should be noted that the housing 141 adopts the form of a regular hexagonal prism, with a magnetoresistive sensor 147 set on each face. This means that a magnetoresistive sensor 147 is placed every 60°, forming a 360° circular detection array. This ensures comprehensive acquisition of leakage magnetic signals across the entire circumference of the pipe's inner wall, effectively capturing changes in the magnetic signal. While an octagonal prism could also be used, considering both economy and capture performance, six magnetoresistive sensors 147 were ultimately employed for signal reception. The magnetoresistive sensors 147 possess extremely high density and resolution, capable of detecting even the weakest changes in leakage magnetic signals. Furthermore, the magnetoresistive sensors 147 can integrate high-precision signal conditioning circuitry, which amplifies, filters, and digitizes the acquired weak magnetic signals, improving signal quality and anti-interference capabilities.

[0056] For example, after the magnetoresistive sensor 147 acquires signals, advanced machine learning algorithms and digital signal processing techniques can be used for data filtering. First, the raw magnetic signal data acquired by the magnetoresistive sensor 147 is preprocessed to remove noise and interference signals. Then, machine learning algorithms are used to extract features and classify the processed data to identify valid signals that truly reflect pipeline defects. Furthermore, to ensure data security and reliability, a data backup and transmission module can be equipped to back up the processed data to internal storage devices in real time and transmit the data to an external monitoring center via wireless or wired communication. Advanced encryption technology is used during data transmission to ensure data security and integrity; however, this is not the focus of this application and will not be elaborated further.

[0057] For example, a monitoring component can be set in the internal detection device 100. When the magnetoresistive sensor 147 in the detection component 140 experiences slight wear, the monitoring component promptly monitors the wear of the magnetoresistive sensor 147. Once the wear is detected to exceed the set safety threshold, the monitoring signal is fed back to the control system. The control system then performs inspection and maintenance based on the received signal.

[0058] It is understandable that the motor can be powered by a battery, and the signal transmission can be wired or wireless, which are all achievable with existing technology and will not be elaborated further.

[0059] Figure 4 This is a schematic diagram of a clamp assembly according to an embodiment of the present invention.

[0060] In one feasible implementation, such as Figure 4 As shown, the detection component 140 and the magnet component 120 are fixedly connected by a clamp assembly 150, which includes: The first push rod 151 is disposed on the detection assembly 140. The first push rod 151 has a first mounting slope 1511 and a first snap-fit ​​surface 1512 on some of its surfaces facing the magnet assembly 120. The second push rod 152 is hinged to the mounting shell of the magnet assembly 120. The second push rod 152 has a second mounting slope 1521 and a second snap-fit ​​surface 1522 on the side facing the first push rod 151. The second mounting slope 1521 matches the first mounting slope 1511. The first push rod 151 and the second push rod 152 are snapped together through the first snap-fit ​​surface 1512 and the second snap-fit ​​surface 1522. The abutment plate 153 is fixedly connected to the mounting shell, and the end of the second push rod 152 away from the detection component 140 abuts against the abutment plate 153.

[0061] The detection assembly 140 includes a first push rod 151 and a second push rod 152 on the sealing plate of the inner magnetic ring and the permanent magnet blocks (S-pole permanent magnet block 122 and N-pole permanent magnet block 123). The second push rod 152 is hinged to the sealing plate, which also has an abutment plate 153. When the second push rod 152 rotates, one end abuts against the abutment plate 153. Figure 4 As shown, during installation, the first mounting slope 1511 of the first push rod 151 pushes the second mounting slope 1521 of the second push rod 152, causing the second push rod 152 to rotate away from the abutment plate 153. After the first push rod 151 is installed in place, the second push rod 152 resets under gravity, meaning the second push rod 152 is about to abut against the abutment plate 153. At this time, due to the misalignment of the first push rod 151 and the second push rod 152, the second push rod 152 can bypass the first push rod 151, and the first engaging surface 1512 of the first push rod 151 engages with the second engaging surface 1522 of the second push rod 152, thereby achieving the engagement of the magnet assembly 120 and the detection assembly 140. It can be understood that three or more clamp assemblies 150 are evenly arranged in the circumferential direction of the detection assembly 140 (magnet assembly 120) to improve the stability of the connection. Understandably, to ensure the stability of the S-pole permanent magnet 122 and the N-pole permanent magnet 123, the sealing plate connecting the second push rod 152 is connected to the S-pole permanent magnet 122 and the N-pole permanent magnet 123 respectively via bearings 155. Figure 4 As shown.

[0062] It should be noted that the second push rod 152 is hinged to the sealing plate by a pin. Two pins 154 can be vertically inserted into the sealing plate. The end of the pin 154 connected to the pin is set to match the shape of the pin to limit and fix the pin. When disassembly is required, the pin 154 is removed. Since the connection between the pin and the second push rod 152 is short, the pin can be dislodged from the second push rod 152 by shaking the sealing plate or the housing 141, so that the second push rod 152 can be dislodged from the sealing plate. In this way, the detection component 140 and the magnet component 120 can be separated for replacement or maintenance.

[0063] It is understandable that the detection component 140 and the magnetic component can also be fixedly connected using elastic clips and elastic retaining rings; or they can be connected using positioning ports and positioning posts. Any method that facilitates the assembly and disassembly of the detection component 140 and the magnetic component 120 is acceptable, and will not be listed individually.

[0064] By setting magnetic rings 124 on both sides of the S-pole permanent magnet 122 and the N-pole permanent magnet 123, magnetic leakage can be effectively prevented. Furthermore, the uniform arrangement of permanent magnets and magnetic rings 124 on both sides of the monitoring component 140 forms a good magnetic leakage shield, ensuring that the monitoring of the magnetic leakage signal is not affected and that the magnetic field is not impacted, thus improving the accuracy of magnetic leakage detection. Specifically, pipeline magnetic leakage detection utilizes a strong magnetic field to magnetize the inner wall of the pipeline to saturation. When a defect exists in the pipeline, the magnetic field will be distorted at the defect location, and some magnetic lines of force will "leak" to the outside of the pipeline. By detecting these "magnetic leakage" signals, the size and location of the defect can be determined. The layout of the magnet component 120 in this application can better magnetize the pipeline and enhance the magnetic signal. The detection component 140 (magnetoresistive sensor 147) collects these distorted magnetic signals in a timely manner and transmits them to an external control system for processing and comparison. This allows for the timely detection of the type and level of pipeline defects, as well as the location of the defects, providing a scientific and accurate basis for pipeline maintenance decisions (such as whether repair is needed and the selection of repair methods). When a pipe is free of defects, magnetic field lines are tightly confined within a low-resistivity loop formed by the magnet and the pipe wall, resulting in a very weak leakage magnetic field outside the pipe. However, when a defect exists, the permeability at the defect point is much lower than that of the steel pipe itself, effectively introducing a high-resistivity region into the magnetic circuit. Since magnetic field lines tend to choose the path of least resistance, the saturated pipe wall cannot accommodate all the magnetic field lines. Some lines are forced to detour by the defect, creating a leakage magnetic field. The detection component 140 continuously acquires the magnetic field strength of the pipe's inner wall. Once it passes a defect, it captures the signal generated by the leakage magnetic field. It is understood that the deeper the defect, the greater the magnetic resistance, and the stronger the magnetic leakage signal; the wider the defect, the wider the signal peak. Sharp defects (such as cracks) and smooth defects (such as corrosion) produce different signal characteristics, which are then learned and compared through subsequent machine learning.

[0065] The inner wall of the pipe is magnetized by the magnet assembly 120, bringing it to magnetic saturation. This means the permeability of the pipe's inner wall drops sharply, making it almost impossible to accommodate more magnetic field lines. This enhances the magnetic flux change at the defect location, making it easier to capture magnetic field change signals and improving the sensitivity of the internal detection device 100. In actual use, the internal detection device 100 is placed at the beginning of the pipe. The internal detection device 100 moves within the pipe by relying on the cooperation of the traction component and / or spiral bristles with the inner wall of the pipe. During movement, the inner wall of the pipe is cleaned by the iron brush 132, and then the pipe is magnetized by the magnet assembly 120. Simultaneously, the drive motor 143 powers the rotation of the housing 141 and the magnetoresistive sensor 147. The magnetoresistive sensor 147 receives the magnetic field change of the magnetic ring 124 and feeds the magnetic signal back to the external control system. As the internal detection device 100 moves inside the pipeline, the permanent magnet 121, the S-pole permanent magnet 122, and the N-pole permanent magnet 123 generate a stable magnetic field to magnetize the pipeline. When there are defects such as corrosion or cracks on the inner wall of the pipeline, magnetic leakage will occur. The high-sensitivity magnetoresistive sensor 147 in the detection component 140 collects the magnetic leakage signal in a timely manner at a high-speed sampling frequency (e.g., thousands of times per second), and converts the collected analog signal into a digital signal through a high-precision analog-to-digital converter module. After being encoded according to a specific data format, it is quickly transmitted to the data filtering module.

[0066] The above describes the tasks of the internal detection device 100 of this application. After receiving the data transmitted by the magnetoresistive sensor 147, the subsequent data filtering module first performs preliminary filtering on the data through a hardware filtering circuit to remove high-frequency noise and power frequency interference. Then, it uses an intelligent software model based on deep learning algorithms to perform in-depth analysis and processing of the data. This model has been trained on a large amount of actual detection data and simulated data containing different types of pipeline defects, and can accurately identify effective signals that truly reflect pipeline defects and extract their features, such as the location, shape, and size of the defects. Data that does not conform to the defect characteristics is considered interference and is discarded. The filtered data is stored according to time and space sequences for subsequent analysis. After the detection is completed, the data stored in the device is transmitted quickly and encrypted to an external data processing center via a wireless communication module (such as using low-power, high-speed 5G or LoRa communication technology) or a wired communication interface (such as a fiber optic interface). The data processing center is equipped with a high-capacity, high-performance storage server to classify and store the transmitted data, while also performing data backup to prevent data loss. At the data processing center, professional pipeline inspection data analysis software is used to perform in-depth mining and analysis of the stored data. The software first visualizes the data, presenting the inspection results in intuitive graphical forms (such as pipeline axial profiles and defect location distribution maps) and charts (such as defect size statistics charts and defect type ratio charts). Then, based on relevant industry standards and specifications (such as pipeline inspection standards for the oil and gas industry), and combined with parameters such as pipeline material, diameter, and service life, it quantitatively and qualitatively assesses the detected pipeline defects. By calculating geometric parameters such as defect depth, length, and width, and evaluating defect development trends, it determines the pipeline's remaining strength and safe operating life, providing a scientific and accurate basis for pipeline maintenance decisions (such as whether repair is needed and the selection of repair methods).

[0067] It is understood that the accompanying drawings of this application are drawn in an enlarged manner for ease of understanding of the drive motor 143, which can be located in the internal gear 142 part, that is, between the detection component 140 and the second support member.

[0068] In this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" refers to two or more unless otherwise expressly defined.

[0069] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only.

[0070] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A magnetic flux leakage internal inspection apparatus for a pipe, characterized by comprising: The internal detection device includes: Install rack; A magnet assembly, fitted onto at least a portion of the mounting frame, the magnet assembly comprising a first magnet group and a second magnet group; A transmission actuator is disposed on the side of the first magnet group opposite to the second magnet group, and the transmission actuator is configured to clean the inner wall of the pipe; A detection component is disposed between the first magnet group and the second magnet group, and the detection component is configured to receive changes in the magnetic field of the magnet group.

2. The magnetic flux leakage detection device for pipelines according to claim 1, characterized in that, The mounting frame includes a first support member and a second support member that are connected to each other, with the second support member passing through the magnet assembly and the detection assembly.

3. The magnetic flux leakage detection device for pipelines according to claim 2, characterized in that, The first support member includes: a pair of support plates, a universal joint between the pair of support plates, both ends of the universal joint passing through the pair of support plates respectively, and the universal joint being fixedly connected to the support plates. Fixed steering shafts are provided on both ends of the universal joint, and the fixed steering shafts extend in a direction away from the support plates.

4. The magnetic flux leakage detection device for pipelines according to claim 1, characterized in that, The first magnet assembly includes an annular N-pole permanent magnet block, the second magnet assembly includes an S-pole permanent magnet block and a permanent magnet block, the permanent magnet block being disposed on the side of the S-pole permanent magnet block away from the N-pole permanent magnet block, and the detection assembly being disposed between the S-pole permanent magnet block and the N-pole permanent magnet block.

5. The magnetic flux leakage detection device for pipelines according to claim 4, characterized in that, The magnet assembly also includes: A magnetic guide ring is disposed on both sides of the N-pole permanent magnet block and on both sides of the S-pole permanent magnet block.

6. The magnetic flux leakage detection device for pipelines according to claim 5, characterized in that, The magnetic ring includes: The ring body is fitted onto the mounting frame, and the ring body forms a receiving space; A cover is provided on both sides of the ring body in the axial direction, and the cover is configured to close the receiving space; A magnetically conductive arc plate is disposed within the accommodating space. Multiple magnetically conductive heads are evenly disposed on the magnetically conductive arc plate. The magnetically conductive heads are located on both sides of the magnetically conductive arc plate and extend toward the sealing direction.

7. The magnetic flux leakage detection device for pipelines according to claim 1, characterized in that, The transmission actuation component includes: A rocker arm bracket is disposed on the side of the first magnet group away from the second magnet group, and the rocker arm bracket is fixedly connected to the mounting frame; The rotating rocker arm is rotatably connected to the rocker arm bracket. An iron brush is disposed at one end of the rotating rocker arm away from the rocker arm support. The iron brush includes a support rod and bristles spirally wound on the support rod.

8. The magnetic flux leakage detection device for pipelines according to claim 7, characterized in that, Multiple springs are provided between the support rod and the rotating rocker arm.

9. The magnetic flux leakage detection device for pipelines according to claim 1, characterized in that, The detection component includes: A housing is fitted onto the mounting frame. Multiple magnetoresistive sensors are evenly arranged on the outer periphery of the housing. The housing has internal teeth on the side facing the mounting frame. A drive motor is located between the second magnet assembly and the housing. The output shaft of the drive motor is provided with a first gear and a second gear, and the first gear meshes with the internal gear. The third gear meshes with the second gear, and the third gear is fixedly connected to the transmission actuation component.

10. The magnetic flux leakage detection device for pipelines according to claim 1, characterized in that, The detection component and the magnet component are fixedly connected by a clamp assembly, the clamp assembly comprising: A first push rod is disposed on the detection assembly, and the first push rod has a first mounting slope and a first snap-fit ​​surface on some of its face toward the magnet assembly; The second push rod is hinged to the mounting shell of the magnet assembly. The second push rod has a second mounting slope and a second snap-fit ​​surface on the side facing the first push rod. The second mounting slope matches the first mounting slope. The first push rod and the second push rod are snap-fitted together through the first snap-fit ​​surface and the second snap-fit ​​surface. An abutment plate is fixedly connected to the mounting shell, and the end of the second push rod away from the detection component abuts against the abutment plate.

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