An inspection device based on stepped eddy current thermal imaging nondestructive testing technology

Abstract

An inspection device based on stepped eddy current thermal imaging nondestructive testing technology includes a chassis support module, a temperature recording module, a power module, and a low-frequency, low-current excitation module. The chassis support module, composed of a nylon plate and a data processing terminal, provides support for the other modules. The data processing terminal is used to process temperature data and solve for defect geometry information. The temperature recording module consists of a main and auxiliary support frame and an infrared thermal imager, which transmits the observed temperature signal to the data processing terminal. The power module consists of wheels and stepper motors. By controlling four sets of stepper motors at different speeds, different speed differences in the wheels are achieved, thereby adjusting the posture of the inspection device during the inspection process. The low-frequency, low-current excitation module consists of a magnetic yoke and a multi-turn coil. When an alternating current is passed through the multi-turn coil, induced eddy currents are generated in the steel plate, causing temperature changes in the steel plate and achieving detection.

Description

Technical Field

[0001] This utility model relates to the field of defect detection technology, specifically to an inspection device based on stepped eddy current thermal imaging non-destructive testing technology. Background Technology

[0002] With the increase in oil and gas production, the scale of crude oil storage tanks in my country is gradually expanding. Due to the highly hazardous nature of the stored media, their safety and reliability are directly related to the stable operation of the energy supply chain, environmental protection, and public safety. The tank bottom plates, which are in long-term contact with the stored media (such as crude oil, weakly acidic hydrosulfuric acid solutions formed by H2S dissolved in water), are susceptible to corrosion, fatigue, and stress concentration. This can lead to defects such as cracks, corrosion pits, and thinning of the bottom plates. If these defects are not detected and addressed in a timely manner, they may cause serious accidents such as leaks, fires, or even explosions, resulting in huge economic losses, environmental damage, and personal injury.

[0003] Traditional inspection methods for tank bottom plates require inspectors to measure the remaining thickness of the steel plate at intervals, using ultrasonic non-destructive testing (NDT) at specific points on the bottom of the plate. Point inspection has a high probability of missing defects and places high demands on the inspectors. Furthermore, ultrasonic testing requires thorough surface cleaning and the application of a coupling agent to achieve accurate measurements at specific points on the steel plate.

[0004] To address this challenge, eddy current thermal imaging nondestructive testing (EDT) technology is used to perform surface inspections over a specific area. However, traditional eddy current thermal imaging relies on high-frequency, high-current excitation sources, which fails to meet the explosion-proof requirements of oil and gas stations. Therefore, this invention constructs an inspection device based on low-frequency, low-current stepped eddy current thermal imaging EDT technology. This device is used to segment and measure defects in environments with explosion-proof requirements. It effectively avoids missed detections caused by improper test point placement during ultrasonic testing and is adaptable to defect detection tasks under certain explosion-proof conditions. It reduces the workload of inspection personnel during the measurement process and avoids human error caused by inspection staff. Furthermore, it lowers the cost of testing, making the testing process more efficient and accurate. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems in the prior art by providing an inspection device based on stepped eddy current thermal imaging non-destructive testing technology.

[0006] The technical solution provided by this utility model to solve the above-mentioned technical problems is as follows:

[0007] An inspection device based on stepped eddy current thermal imaging, the device includes a chassis support module, a temperature recording module, a power module, a low-frequency low-current excitation module, etc.

[0008] The chassis support module is fastened by two L-shaped nylon plates and two transversely reinforcing nylon plates through a tenon and mortise structure. The L-shaped nylon plates have two grooves evenly distributed on one side for embedding stepper motors. Both L-shaped nylon plates have slots on the side where the motors are embedded for embedding lithium battery boxes and data processing terminals. The data processing terminal is used to extract temperature time-series image data for processing, segment the defect morphology and solve for the remaining thickness of the steel plate at the defect, and locate the defect location information by inverse kinematics.

[0009] The temperature recording module consists of a main and a secondary support and an infrared thermal imager. The main and secondary supports are fastened to the top of the lithium battery box and the top of the data processing terminal by a first bolt and a first nut, respectively. The infrared thermal imager is fixed by a clamping device formed by the main and secondary supports and a second bolt and a second nut. The infrared thermal imager transmits the observed temperature signal to the data processing terminal via a wireless signal.

[0010] The power module consists of stepper motors and lithium batteries. There are four sets of stepper motors embedded in the grooves of the L-shaped nylon plate. The drive shaft of the stepper motor is fastened to the wheel by an internal hexagonal nut. The lithium battery is located in the lithium battery box, which is fixed to the side of the L-shaped nylon plate by a slot. By controlling the different speeds of the four sets of stepper motors, different speed differences are achieved in the wheel, thereby realizing the attitude adjustment of the inspection device during the inspection process.

[0011] The low-frequency, low-current excitation module consists of a manganese-zinc ferrite yoke and a multi-turn copper coil winding. The four sets of manganese-zinc ferrite yokes are divided into two sets of manganese-zinc ferrite yoke horizontal arm ends and two sets of manganese-zinc ferrite yoke winding ends. The two sets of manganese-zinc ferrite yoke horizontal arm sections are respectively embedded in the grooves of two L-shaped nylon plates. The two sets of manganese-zinc ferrite yoke winding ends are respectively wound with multi-turn copper coils. The two sets of manganese-zinc ferrite yoke winding ends are placed perpendicular to the manganese-zinc ferrite yoke horizontal arm ends at both ends of the manganese-zinc ferrite yoke horizontal arm sections and are fixed by limiting baffles. A 50Hz alternating current is passed through the multi-turn copper coil windings, which generates eddy currents in the detection steel plate, thereby causing a temperature change in the detection steel plate.

[0012] The beneficial effects of this utility model are that it can realize dynamic detection and surface detection, flexible turning, high versatility, high economic benefits, and good detection efficiency, and can realize defect measurement tasks with certain explosion-proof requirements. Attached Figure Description

[0013] Figure 1 This is a three-dimensional view of an inspection device based on stepped eddy current thermal imaging non-destructive testing technology according to this utility model.

[0014] Figure 2This is a 3D view of the chassis support module.

[0015] Figure 3 This is a 3D view of the temperature recording module.

[0016] Figure 4 This is a 3D diagram of the power module.

[0017] Figure 5 This is a 3D view of the low-frequency, low-current excitation module.

[0018] In the diagram, 1. Wheel, 2. Lithium battery box, 3. Stepper motor, 4. Main limit baffle, 5. Multi-turn copper coil winding, 6. Data processing terminal, 7. Power controller, 8. Lateral reinforcing nylon plate, 9. Secondary limit baffle, 10. Lithium battery box fixing slot, 11. Main L-shaped nylon plate, 12. Secondary L-shaped nylon plate, 13. Data terminal fixing slot, 14. First bolt, 15. First nut, 16. Main clamping bracket, 17. Second bolt, 18. Second nut, 19. Infrared thermal imager, 20. Secondary clamping bracket, 21. Drive shaft, 22. Hex socket nut, 23. Motor slot, 24. Manganese-zinc ferrite yoke cross arm end, 25. Manganese-zinc ferrite yoke winding end. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings:

[0020] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, an inspection device based on stepped eddy current thermal imaging non-destructive testing technology includes a chassis support module, a temperature recording module, a power module, and a low-frequency low-current excitation module.

[0021] The chassis support module includes: 2. a lithium battery box, 6. a data processing terminal, 8. a transverse reinforcing nylon plate, 10. a lithium battery box fixing slot, 11. a main L-shaped nylon plate, 12. a secondary L-shaped nylon plate, and 13. a data terminal fixing slot. The data processing terminal 6 is connected to the L-shaped nylon plate B12 through the data terminal fixing slot 13. The lithium battery box 2 is connected to the main L-shaped nylon plate 11 through the lithium battery box fixing slot 10. The protrusions at both ends of the transverse reinforcing nylon plate 8 respectively engage with the grooves of the secondary L-shaped nylon plate 12 and the main L-shaped nylon plate 11 to form a fixed connection. The data processing terminal 6 is used for processing temperature data and solving for defect geometric information.

[0022] The temperature recording module includes: 14. a first bolt, 15. a first nut, 16. a main clamping bracket, 17. a second bolt, 18. a second nut, 19. an infrared thermal imager, and 20. a secondary clamping bracket. The main clamping bracket 16 is fixed to the top of the data processing terminal 6 by a bolt-nut fastener formed by the first bolt 14 and the first nut 15. The secondary clamping bracket 20 is fixed to the top of the lithium battery box 2 by a bolt-nut fastener formed by the first bolt 14 and the first nut 15. The infrared thermal imager 19 is fixed by the main clamping bracket 16 and the secondary clamping bracket 20. The clamping force is controlled by a bolt-nut fastener formed by the second bolt 17 and the second nut 18. The infrared thermal imager 19 wirelessly transmits the time-series temperature data of the detected heating area to the data processing terminal 6.

[0023] The power module includes: 1. wheels, 2. lithium battery box, 3. stepper motors, 21. drive shaft, 22. hexagonal nuts, and 23. motor slots. The stepper motors 3 consist of four sets, each embedded in one of the four built-in motor slots 23 of the secondary L-shaped nylon plate 12 and the main L-shaped nylon plate 11. The wheels 1 also consist of four sets and are securely connected to the drive shaft 21 via hexagonal nuts 22. The drive shaft 21 is a component of the stepper motors 3. The stepper motors 3 are powered by lithium batteries in the lithium battery box 2. The stepper motors 3 are connected to the wheels 1 via the drive shaft 21. By controlling the different speeds of the four stepper motors, different speed differences in the wheels are achieved, thereby adjusting the posture of the inspection device during the inspection process.

[0024] The low-frequency, low-current excitation module includes: 5. a multi-turn copper coil winding, 7. a power controller, 9. a secondary limiting baffle, 11. a main L-shaped nylon plate, 12. a secondary L-shaped nylon plate, 24. a manganese-zinc ferrite yoke cross arm end, and 25. a manganese-zinc ferrite yoke winding end. There are two sets of manganese-zinc ferrite yoke cross arm ends 24, which are respectively installed in the grooves of the main L-shaped nylon plate 11 and the secondary L-shaped nylon plate 12. There are two sets of manganese-zinc ferrite yoke winding ends 25, each with a multi-turn copper coil winding 5 wound around its periphery. The wound manganese-zinc ferrite yoke winding ends 25 are placed perpendicular to the manganese-zinc ferrite yoke cross arm ends 24 at both ends of the manganese-zinc ferrite yoke cross arm ends 24 and fixed by the main limiting baffle 4 and the secondary limiting baffle 9, forming a square open area for heating. The input and output terminals of the multi-turn copper coil winding 5 are connected to the power controller 7. The power controller 7 adjusts the input current of the multi-turn copper coil winding 5 to control the heating effect in the open area. The power controller 7 is integrated with the data processing terminal 6 and connected to the secondary L-shaped nylon plate 12 through the data terminal fixing slot 13. By inputting a 50Hz alternating current to the power controller 7, an alternating magnetic field is generated in the monitoring area, causing eddy currents in the steel plate and resulting in temperature rise. The surface temperature of the steel plate is monitored by the infrared thermal imager 19 to achieve defect detection.

Claims

1. A ladder-type eddy current thermography-based non-destructive testing device, comprising a chassis support module, a temperature recording module, a power module, and a low-frequency low-current excitation module, characterized in that: The chassis support module consists of a nylon plate, a data processing terminal, and a lithium battery box. The nylon plate is divided into a main L-shaped nylon plate (11), a secondary L-shaped nylon plate (12), and a transversely reinforcing nylon plate (8). The protrusions at both ends of the transversely reinforcing nylon plate (8) are respectively fitted into the grooves of the secondary L-shaped nylon plate (12) and the main L-shaped nylon plate (11) to form a fixed connection. The lithium battery box (2) is connected to the main L-shaped nylon plate (11) through a lithium battery box fixing slot (10). The data processing terminal (6) is connected to the secondary L-shaped nylon plate (12) through a data terminal fixing slot (13). The data processing terminal (6) is used to process temperature data and solve for defect geometric information. The temperature recording module consists of a main clamping bracket (16). The auxiliary clamping bracket (20) and the infrared thermal imager (19) are combined. The main clamping bracket (16) is fixed to the top of the data processing terminal (6) by a bolt and nut fastener formed by the first bolt (14) and the first nut (15). The auxiliary clamping bracket (20) is fixed to the top of the lithium battery box (2) by a bolt and nut fastener formed by the first bolt (14) and the first nut (15). The infrared thermal imager (19) is fixed by the main clamping bracket (16) and the auxiliary clamping bracket (20). The clamping force is controlled by a bolt and nut fastener formed by the second bolt (17) and the second nut (18). The infrared thermal imager (19) transmits the observed temperature signal to the data processing terminal. The power module consists of wheels (1). The system consists of four sets of stepper motors (3), each embedded in the built-in motor slots (23) of the secondary L-shaped nylon plate (12) and the main L-shaped nylon plate (11). The wheels (1) also consist of four sets and are fastened to the drive shaft (21) via hexagonal nuts (22). The drive shaft (21) is a component of the stepper motors (3). The stepper motors (3) are connected to the wheels (1) via the drive shaft (21). By controlling the different speeds of the four sets of stepper motors (3), different speed differences are achieved in the wheels (1), thereby adjusting the posture of the inspection device during the inspection process. The low-frequency low-current excitation module consists of a multi-turn copper coil winding (5), a manganese-zinc ferrite yoke crossarm end (24), and a manganese-zinc ferrite yoke winding end (5). 25) The manganese zinc ferrite yoke cross arm end (24) has two sets, which are respectively installed in the grooves of the main L-shaped nylon plate (11) and the secondary L-shaped nylon plate (12). The manganese zinc ferrite yoke winding end (25) has two sets, each with multiple turns of copper coil winding (5) wound around the periphery. The wound manganese zinc ferrite yoke winding end (25) is placed perpendicular to the manganese zinc ferrite yoke cross arm end (24) at both ends of the manganese zinc ferrite yoke cross arm end (24) and fixed by the main limit baffle (4) and the secondary limit baffle (9). A 50Hz alternating current is applied to the power controller (7), and an alternating magnetic field is generated in the monitoring area. Eddy currents appear in the steel plate, causing the temperature to rise. The surface temperature change of the steel plate is monitored by the infrared thermal imager (19) to achieve defect detection.

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