A pulsed eddy current flaw detector for easy and rapid detection

Abstract

This invention belongs to the field of electromagnetic nondestructive testing technology and discloses a pulsed eddy current flaw detector for rapid testing. It includes a housing with a handle fixedly connected to its upper end. An equipment cavity is located inside the housing, and an insulating magnetic shielding plate is fixedly installed in the middle of the upper surface of the equipment cavity. Through the design of the base, cam, and support rod, this invention ensures that the bottom and side support devices of the base are tangent to the outer wall of the pipe under the pressure of the operator's hand. This places the probe, i.e., the excitation coil, in contact with the pipe, allowing for automatic alignment. The operation is convenient, quick, and efficient. It not only avoids the problem of the gap between the probe and the pipe affecting the detection results, effectively improving testing efficiency, but also overcomes the signal fluctuations caused by eccentricity and shaking during the testing process of existing pulsed eddy current probes. Furthermore, the probe is always in contact with the pipe, eliminating the need to consider errors caused by different detection distances.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic nondestructive testing technology, specifically a pulse eddy current flaw detector that facilitates rapid testing. Background Technology

[0002] In recent years, pipelines have been widely used worldwide by petrochemical and chemical enterprises as a safe and economical means of transporting large quantities of oil and various high- and low-temperature gases. However, due to the complex operating environment of these pipelines, corrosion of insulated pipelines and pressure vessels such as storage tanks has become a major problem. To ensure the safe operation of oil and gas pipelines and extend their service life, regular inspections are necessary to identify problems and take appropriate measures to ensure safe and reliable pipeline operation. Pulse eddy current flaw detectors have become the preferred choice for inspecting pipeline walls in recent years due to their advantages of high speed, high safety, and low cost. Pulse eddy current flaw detectors mainly work by passing a DC current through a coil, which generates a stable magnetic field within the component over a certain period. When the DC current is disconnected, the electromagnetic field generated around the coil consists of two superimposed parts: one part is the primary electromagnetic field directly coupled from the coil; the other part is the secondary electromagnetic field generated by the eddy current field induced in the component, which contains information such as the thickness or defects of the component itself.

[0003] However, pulsed eddy current flaw detectors have the following shortcomings in actual testing: First, during testing, the probe of the pulsed eddy current flaw detector needs to be manually placed on the area of ​​the pipe to be tested. Because the outer wall of the pipe is cylindrical, compared to a flat plate, the probe is prone to shaking during testing. The resulting interference signal will significantly affect the accuracy of the test. At the same time, the probe is prone to being off-center relative to the pipe during testing, meaning the probe is not directly aligned with the center of the pipe. This will alter the distribution of induced eddy currents in the tested area, and the signal will also change accordingly, leading to testing errors. Second, when testing pipelines, various pipe diameters are encountered. The same problems will occur when testing pipes of different diameters, meaning the testing is difficult and the test values ​​are prone to large errors. Summary of the Invention

[0004] The purpose of this invention is to provide a pulsed eddy current flaw detector that facilitates rapid detection, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a pulse eddy current flaw detector for rapid detection, comprising a housing, a handle fixedly connected to the upper end of the housing, an equipment cavity provided inside the housing, an insulating magnetic plate fixedly installed in the middle of the upper surface of the equipment cavity, support springs fixedly installed on both sides of the upper surface of the equipment cavity, connecting blocks fixedly connected to the bottom ends of the two sets of support springs, a base movably sleeved with the housing fixedly connected to one end of the connecting block, an excitation coil fixedly installed in the middle of the upper end of the base, a receiving coil fixedly installed on the outer side of the middle of the upper end of the base, two sets of support springs fixedly connected to the inner side of the handle, a slider movably sleeved with the handle fixedly connected to the bottom end of the support spring, a connecting rope fixedly connected to the middle of the upper end of the slider, the end of the connecting rope away from the slider being divided into two strands, and the connecting rope passing through the housing and fixedly connected to the two sets of connecting blocks.

[0006] Preferably, an installation cavity is provided above the equipment cavity and located inside the housing. A motor is fixedly installed at the bottom of the installation cavity, and a cam is fixedly connected to the output shaft end of the motor. First hydraulic cavities are provided on both sides of the installation cavity and located inside the housing. A first piston is movably sleeved inside the first hydraulic cavity. A connecting rod extending into the installation cavity is fixedly connected to the middle of one end of the first piston. Second hydraulic cavities are provided on both sides of the equipment cavity and located inside the housing. A connecting channel is connected to the upper end of the second hydraulic cavity and its other end is connected to the first hydraulic cavity. A return spring is fixedly connected to the outer side of the upper end of the second hydraulic cavity. A second piston is fixedly connected to the bottom end of the return spring. The first hydraulic cavity, the connecting channel, and the second hydraulic cavity are filled with hydraulic oil. A support rod that is movably sleeved with the housing is fixedly connected to the middle of the bottom end of the second piston. A support device is provided at the bottom of the support rod.

[0007] Preferably, the support device includes a cavity formed in the middle of the bottom end of the support rod and first contact plates fixedly installed on both sides of the bottom end of the support rod. A connecting spring is fixedly installed inside the cavity. The bottom end of the connecting spring is fixedly connected to a support body that is movably sleeved with the support rod. Two sets of second contact plates corresponding to the positions of the first contact plates are fixedly connected inside the support body. A lamp sheet is fixedly installed on the upper part of the outer surface of the support body.

[0008] Preferably, the elastic force of the support spring is greater than that of the supporting spring, and the connecting rope is an inelastic rope.

[0009] Preferably, the cam is a projecting structure that is completely symmetrical on both sides, and both the upper and lower surfaces of the cam are provided with flanges.

[0010] Preferably, the support is a straight, long rod, and the bottom surface of the support is an arc surface.

[0011] The beneficial effects of this invention are as follows:

[0012] 1. This invention, through the arrangement of a base, cam, and support rod, ensures that the bottom and side support devices of the base are tangent to the outer wall of the pipe under the pressure of the operator's hand. This allows the probe, i.e., the excitation coil, to be in contact with the pipe and automatically align with it. The operation is convenient, quick, and efficient. It not only avoids the problem of the gap between the probe and the pipe affecting the detection results and effectively improves the detection efficiency, but also overcomes the signal fluctuations caused by eccentricity and shaking during the detection process of existing pulse eddy current probes. Furthermore, the probe is always in contact with the pipe, eliminating the need to consider errors caused by different detection distances.

[0013] 2. This invention, through the setting of the support device, ensures that when the pulse eddy current flaw detector shifts, only one side of the support device is tangent to the pipe, while the other side loses its contact pressure. At this time, the support body will slightly extend under the action of the connecting spring, causing the first and second contact plates to separate, thus cutting off the power to the lamp and extinguishing it. When the support devices at the bottom of the base and on both sides are tangent to the outer wall of the pipe, the first and second contact plates are in contact, and the lamp is powered on and illuminated. The operator can then distinguish whether the pulse eddy current flaw detector is aligned by observing the working state of the lamp, make appropriate adjustments, and ensure that the detection position is aligned before performing accurate detection and completing the detection work. Attached Figure Description

[0014] Figure 1 This is a side view of the structure of the present invention;

[0015] Figure 2 This is a schematic diagram of the overall structure of the present invention;

[0016] Figure 3 This is a schematic diagram of the structural support device of the present invention;

[0017] Figure 4 This is a schematic diagram of the cam structure of the present invention.

[0018] In the diagram: 1. Housing; 2. Handle; 3. Equipment cavity; 4. Support spring; 5. Connecting block; 6. Base; 7. Excitation coil; 8. Receiving coil; 9. Support spring; 10. Slider; 11. Connecting rope; 12. Mounting cavity; 13. Motor; 14. Cam; 15. First hydraulic cavity; 16. First piston; 17. Connecting rod; 18. Second hydraulic cavity; 19. Connecting channel; 20. Hydraulic oil; 21. Return spring; 22. Second piston; 23. Support rod; 24. Support device; 241. Cavity; 242. First contact piece; 243. Connecting spring; 244. Support body; 245. Second contact piece; 246. Lamp sheet; 25. Insulating magnetic shielding plate. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] like Figures 1 to 2 As shown, this embodiment of the invention provides a pulsed eddy current flaw detector for easy and rapid detection, including a housing 1. A handle 2 is fixedly connected to the upper end of the housing 1. An equipment cavity 3 is provided inside the housing 1. An insulating magnetic shielding plate 25 is fixedly installed in the middle of the upper surface of the equipment cavity 3. Support springs 4 are fixedly installed on both sides of the upper surface of the equipment cavity 3. Connecting blocks 5 are fixedly connected to the bottom ends of the two sets of support springs 4. A base 6 that is movably sleeved with the housing 1 is fixedly connected to one end of the connecting block 5. An excitation coil 7 is fixedly installed in the middle of the upper end of the base 6. A receiving coil 8 is fixedly installed on the outer side of the middle of the upper end of the base 6. Two sets of support springs 9 are fixedly connected to the inner side of the handle 2. A slider 10 that is movably sleeved with the handle 2 is fixedly connected to the bottom end of the support springs 9. A connecting rope 11 is fixedly connected to the middle of the upper end of the slider 10. The end of the connecting rope 11 away from the slider 10 is divided into two strands, and the connecting rope 11 passes through the housing 1 and is fixedly connected to the two sets of connecting blocks 5.

[0021] like Figure 1-3As shown, an installation cavity 12 is provided above the equipment cavity 3, located inside the housing 1. A motor 13 is fixedly installed at the bottom of the installation cavity 12, and a cam 14 is fixedly connected to the output shaft end of the motor 13. First hydraulic cavities 15 are provided on both sides of the installation cavity 12, located inside the housing 1. A first piston 16 is movably sleeved inside the first hydraulic cavity 15. A connecting rod 17 extending into the installation cavity 12 is fixedly connected to the middle of one end of the first piston 16. Second hydraulic cavities 18 are provided on both sides of the equipment cavity 3, located inside the housing 1. A connecting channel 19, the other end of which communicates with the first hydraulic cavity 15, is connected to the upper end of the second hydraulic cavity 18. A return spring 21 is fixedly connected to the outer side of the upper end of the second hydraulic cavity 18, and a second piston 22 is fixedly connected to the bottom end of the return spring 21. The first hydraulic chamber 15, the connecting channel 19, and the second hydraulic chamber 18 are filled with hydraulic oil 20. A support rod 23 that is movably sleeved with the housing 1 is fixedly connected to the middle of the bottom end of the second piston 22. A support device 24 is provided at the bottom of the support rod 23. The support device 24 includes a cavity 241 opened in the middle of the bottom end of the support rod 23 and a first electrical contact piece 242 fixedly installed on both sides of the bottom end of the support rod 23. A connecting spring 243 is fixedly installed inside the cavity 241. A support body 244 that is movably sleeved with the support rod 23 is fixedly connected to the bottom end of the connecting spring 243. Two sets of second electrical contact pieces 245 corresponding to the positions of the first electrical contact pieces 242 are fixedly connected inside the support body 244. A lamp piece 246 is fixedly installed on the upper part of the outer surface of the support body 244.

[0022] Among them, the elastic force of the support spring 9 is greater than that of the support spring 4, and the connecting rope 11 is an inelastic rope. When idle, the support spring 9 can compress the support spring 4 through its own elastic force, so that the base is inside the equipment cavity when idle, protecting it and preventing it from being bumped.

[0023] like Figure 4 As shown, the cam 14 is a protruding structure that is completely symmetrical on both sides, and both the upper and lower surfaces of the cam 14 are provided with flanges. When the cam 14 rotates, it can simultaneously push the connecting rods 17 on both sides to move the same distance, so that the extension degree of the support devices 24 on both sides is exactly the same. This ensures that the bottom of the base 6 and the support devices 24 on both sides are in a concentric position when they are tangent to the outer wall of the pipe, thus improving the detection accuracy.

[0024] The support body 244 is a straight, long rod, and its bottom surface is set as an arc surface, which makes it easy for the support body 244 to be tangent to the test pipes of different diameters during pipe inspection, so as to facilitate quick alignment and improve work efficiency.

[0025] Working principle and usage process:

[0026] The operator holds handle 2 and places the pulse eddy current flaw detector against the area to be inspected on the pipe surface. The operator controls the rotation of motor 13, which in turn rotates cam 14. Cam 14 then moves the connecting rods 17 on both sides, thereby pushing the support rod 23 outwards via the first piston 16, hydraulic oil 20, and second piston 22. This brings the support devices 24 on both sides into complete contact with the outer wall of the pipe. By gripping the handle, the operator causes the slider 10 to retract upwards, which in turn moves the connecting rope 11 upwards. This releases the rope relative to the inside of the equipment cavity 3, allowing the rope inside the equipment cavity 3 to move further upwards. Under the rebound action of the support spring 4, the base 6 of the device extends out of the equipment cavity 3 until the base 6 contacts the outer wall of the pipe. At this time, under the pressure of the operator's hand, the bottom and the support devices 24 on both sides of the base 6 are tangent to the outer wall of the pipe, so that the probe, i.e. the excitation coil 7, is in contact with the pipe and can automatically align with the pipe. This is convenient and quick. It can not only avoid the problem of the gap between the probe and the pipe affecting the detection results, but also effectively improve the detection efficiency. Moreover, it overcomes the signal fluctuation caused by eccentricity and shaking during the detection process of the existing pulse eddy current probe.

[0027] If the operator's hand shakes or the probe position changes due to a pipe of the same size, it is difficult to effectively ensure that the bottom and side support devices 24 of the base 6 are tangent to the pipe. That is, the base 6 can be firmly pressed, but the pulse eddy current flaw detector is prone to a certain degree of displacement, resulting in only one side support device 24 being tangent to the pipe. At this time, the extension of the two side support devices 24 is fixed, so it is difficult to effectively observe that both side support devices 24 are tangent to the pipe. The setting of the support devices 24 ensures that even if the pulse eddy current flaw detector is displaced, only one side support device 24 is tangent to the pipe. When tangent, the other side support device 24 will lose its contact pressure. At this time, the support body 244 will extend slightly under the elastic force of the connecting spring 243, causing the first contact piece 242 to separate from the second contact piece 245, de-energizing the lamp piece 246 and extinguishing it. When the support devices 24 at the bottom and on both sides of the base 6 are tangent to the outer wall of the pipe, the first contact piece 242 and the second contact piece 245 will contact each other, and the lamp piece 246 will be energized and illuminated. The operator can then distinguish whether the pulse eddy current flaw detector is aligned by observing the working state of the lamp piece 246, and after making appropriate adjustments, the detection work can be completed.

[0028] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pulse eddy current flaw detector for rapid detection, comprising a housing (1), wherein a handle (2) is fixedly connected to the upper end of the housing (1), characterized in that: The housing (1) has an internal equipment cavity (3). An insulating magnetic shielding plate (25) is fixedly installed in the middle of the upper surface of the equipment cavity (3). Support springs (4) are fixedly installed on both sides of the upper surface of the equipment cavity (3). A connecting block (5) is fixedly connected to the bottom of the two sets of support springs (4). A base (6) that is movably connected to the housing (1) is fixedly connected to one end of the connecting block (5). An excitation coil (7) is fixedly installed in the middle of the upper end of the base (6). A receiving coil (8) is fixedly installed on the outer side of the middle of the upper end of the base (6). Two sets of support springs (9) are fixedly connected to the inner side of the handle (2). A slider (10) that is movably connected to the bottom of the support spring (9) is fixedly connected to the handle (2). A connecting rope (11) is fixedly connected to the middle of the upper end of the slider (10). The end of the connecting rope (11) away from the slider (10) is divided into two strands, and the connecting rope (11) passes through the housing (1) and is fixedly connected to the two sets of connecting blocks (5). The elastic force of the support spring (9) is greater than that of the support spring (4), and the connecting rope (11) is an inelastic rope.

2. The pulse eddy current flaw detector according to claim 1, characterized in that: Above the equipment cavity (3) is an installation cavity (12) located inside the housing (1). A motor (13) is fixedly installed at the bottom of the installation cavity (12). A cam (14) is fixedly connected to the output shaft end of the motor (13). A first hydraulic cavity (15) is provided on both sides of the installation cavity (12) inside the housing (1). A first piston (16) is movably sleeved inside the first hydraulic cavity (15). A connecting rod (17) extending into the installation cavity (12) is fixedly connected to the middle of one end of the first piston (16). A second hydraulic cavity is provided on both sides of the equipment cavity (3) inside the housing (1). The upper end of the second hydraulic chamber (18) is connected to a connecting channel (19) that is connected to the first hydraulic chamber (15) at the other end. A return spring (21) is fixedly connected to the outer side of the upper end of the second hydraulic chamber (18). A second piston (22) is fixedly connected to the bottom end of the return spring (21). The first hydraulic chamber (15), the connecting channel (19), and the second hydraulic chamber (18) are filled with hydraulic oil (20). A support rod (23) that is movably sleeved with the housing (1) is fixedly connected to the middle part of the bottom end of the second piston (22). A support device (24) is provided at the bottom of the support rod (23).

3. The pulse eddy current flaw detector according to claim 2, characterized in that: The support device (24) includes a cavity (241) opened in the middle of the bottom end of the support rod (23) and a first contact piece (242) fixedly installed on both sides of the bottom end of the support rod (23). A connecting spring (243) is fixedly installed inside the cavity (241). A support body (244) that is movably sleeved with the support rod (23) is fixedly connected to the bottom end of the connecting spring (243). Two sets of second contact pieces (245) corresponding to the positions of the first contact pieces (242) are fixedly connected inside the support body (244). A lamp piece (246) is fixedly installed on the upper part of the outer surface of the support body (244).

4. The pulse eddy current flaw detector according to claim 2, characterized in that: The cam (14) is a protruding structure that is completely symmetrical on both sides, and both the upper and lower surfaces of the cam (14) are provided with flanges.

5. A pulse eddy current flaw detector for rapid detection according to claim 3, characterized in that: The support (244) is a straight long rod, and the bottom surface of the support (244) is set as an arc surface.

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