A kind of support insulator and magnetic sleeve phased array ultrasonic detection method

Abstract

The application relates to the technical field of insulator detection, and discloses a magnetic sleeve phase-controlled array ultrasonic detection method for a post insulator, which comprises an insulator body, an upper flange and a lower flange, the upper flange and the lower flange are respectively arranged at the top and the bottom of the insulator body, a sound guide groove is arranged in the outer wall of the insulator body, the sound guide groove is filled with solidified sound guide glue, the outer wall of the insulator body is provided with an umbrella skirt, the upper flange and the lower flange are provided with magnetic coding tracks, and the outer wall of the magnetic coding track is provided with a plurality of magnetic force marking points. The magnetic coding tracks with equidistant magnetic force marking points are arranged on the outer circumferential surfaces of the upper flange and the lower flange, the magnetic wheels on the C-shaped magnetic sleeve carriers and the Hall sensors are matched, the accurate position coding and feedback of probe circumferential movement are realized, the detection results of the same insulator can be directly compared, the long-term tracking of defect development is facilitated, and the uncontrollable manual scanning path and the positioning experience-dependent defects are solved.

Description

Technical Field

[0001] This invention relates to the field of insulator testing technology, specifically to an ultrasonic testing method for post insulators and magnetic sleeve phased array insulators. Background Technology

[0002] Post insulators are among the most widely used and most frequently failing core components in substations and overhead transmission lines. They typically consist of a porcelain insulator body and metal flanges at both ends, fixed together with cement or epoxy adhesive. During long-term operation, wind vibration, temperature differences, electrodynamic forces, manufacturing residual stress, and environmental corrosion can easily lead to cracks, pores, and inclusions within the porcelain insulator body. Furthermore, the bonding interface between the flanges and the porcelain body is prone to detachment or partial separation. If these defects are not detected in time, they can cause insulator breakage, resulting in widespread power outages.

[0003] Existing non-destructive testing methods for post insulators mainly rely on infrared thermography and conventional single-point ultrasonic testing. Infrared methods cannot detect tiny cracks inside the ceramic body or hidden debonding at the flange bonding interface. Conventional ultrasonic testing requires manually moving the probe point by point on the insulator surface, which is extremely inefficient and difficult to form a stable coupling due to interference from the shed structure. At the same time, probe positioning depends entirely on the operator's experience, and the scanning path cannot be repeated, resulting in large defect location errors and a high rate of missed detection. Summary of the Invention

[0004] This invention provides an ultrasonic testing method for post insulators and magnetic sleeve phased arrays, which solves the problems mentioned in the background art.

[0005] The present invention provides the following technical solution: a post insulator, comprising an insulator body, an upper flange and a lower flange, wherein the upper flange and the lower flange are respectively installed on the top and bottom of the insulator body, the outer wall of the insulator body is provided with a sound-guiding groove, the sound-guiding groove is filled with cured sound-guiding adhesive, the outer wall of the insulator body is provided with a skirt, and the upper flange and the lower flange are provided with magnetic coding tracks, wherein the outer wall of the magnetic coding tracks is distributed with a plurality of magnetic marking points.

[0006] As a preferred embodiment of the present invention, a guide groove is provided on the outer wall of the insulator body, and the guide groove is located at the outer edge of the sound-guiding groove.

[0007] As a preferred embodiment of the present invention, the cross-sectional shape of the sound-guiding groove is arc-shaped, the width of the sound-guiding groove is 2mm-8mm, and the depth is 1mm-3mm; the sound-guiding adhesive is room temperature vulcanizing silicone rubber or epoxy-based ultrasonic coupling material, and the difference between its acoustic impedance and the acoustic impedance of the insulator body ceramic material is less than ±10%.

[0008] As a preferred embodiment of the present invention, the magnetic coding track is installed on the outer wall of the upper flange and the lower flange, the magnetic marking points are embedded and spaced on the magnetic coding track, and the central angle between each magnetic marking point is 5°-30°.

[0009] A phased array ultrasonic testing method for magnetic sleeves of post insulators includes the following steps: S1: A flexible phased array probe is fixed inside a magnetic sleeve carrier. The magnetic sleeve carrier has an arc-shaped or C-shaped clamp structure, and three to six rolling magnetic wheels are installed on its inner side. S2: Adsorb the magnetic sleeve carrier onto the magnetic coding track, so that the working surface of the phased array probe comes into contact with the magnetic coding track; S3: The magnetic sleeve carrier moves circumferentially along the magnetic coding track. Whenever it passes a magnetic marker point, a position trigger signal is generated by the Hall sensor or magnetic encoder, and the phased array ultrasonic system simultaneously acquires a frame of ultrasonic echo data. S4: Use full focusing or synthetic aperture focusing to reconstruct images of multiple frames of data to obtain defect images of the insulator body and flange bonding interface; S5: Compare the reconstructed image with the preset defect feature library and output the defect type, location and size.

[0010] As a preferred embodiment of the present invention, the magnetic sleeve carrier and the magnetic wheel are both made of insulating materials or have an insulating covering layer, so that the entire detection device is suitable for live-line working scenarios and can detect equipment with voltage levels of 110kV and above at a safe distance.

[0011] As a preferred embodiment of the present invention, the phased array probe has 16-128 array elements, a center frequency of 2.5MHz-10MHz, and uses linear scanning or sector scanning for electronic scanning, with a scanning angle range of -30° to +30°.

[0012] As a preferred technical solution of the present invention, in S3, the phased array system acquires a set of full matrix acquisition data at each trigger point. The full matrix acquisition data includes the time domain signal of all transmit and receive array elements, which is used for subsequent full focusing reconstruction.

[0013] As a preferred technical solution of the present invention, when the insulator body is provided with two or more upper and lower sound-conducting grooves, each groove is scanned in sequence, and the data obtained from each scan are spliced ​​and fused according to the axial coordinate to form a three-dimensional ultrasonic test image of the entire insulator body.

[0014] As a preferred embodiment of the present invention, it further includes the steps of cleaning the sound-guiding groove and replenishing the sound-guiding adhesive before testing, and the step of sealing and protecting the sound-guiding groove after testing.

[0015] The present invention has the following beneficial effects: 1. The phased array ultrasonic testing method for post insulators and magnetic sleeves achieves precise position encoding and feedback of the probe's movement along the circumference of the insulator by setting magnetic coding tracks with equally spaced magnetic marking points on the outer circumferential surface of the upper and lower flanges, in conjunction with magnetic wheels and Hall sensors on the C-shaped magnetic sleeve carrier. The test results of multiple tests on the same insulator can be directly compared, which is convenient for long-term tracking of defect development and solves the defects of existing manual scanning paths being uncontrollable and positioning relying on experience.

[0016] 2. The ultrasonic testing method for post insulators and magnetic sleeves using phased array technology provides a flat, continuous, and acoustically impedance-matched acoustic window for the flexible phased array probe by pre-opening sound-guiding grooves on the smooth cylindrical surface between the umbrella skirts of the post insulator and filling them with sound-guiding adhesive. This completely solves the problem of unstable coupling caused by interference between curved surfaces and umbrella skirts in traditional ultrasonic testing, and significantly improves the detection rate of micro-cracks and debonding of adhesive interfaces. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure of the present invention; Figure 3 For the present invention Figure 2 Enlarged structural diagram at point A in the diagram; Figure 4 This is a schematic diagram of the magnetic coding track and magnetic sleeve carrier structure of the present invention.

[0018] In the diagram: 1. Insulator body; 2. Upper flange; 3. Lower flange; 4. Sound guiding groove; 5. Sound guiding adhesive; 6. Magnetic coding track; 7. Umbrella skirt; 8. Phased array probe; 9. Magnetic sleeve carrier; 10. Magnetic wheel; 61. Magnetic marker point. 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] Please see Figures 1-4A post insulator includes an insulator body 1, an upper flange 2, and a lower flange 3. The upper flange 2 and the lower flange 3 are respectively installed on the top and bottom of the insulator body 1. The outer wall of the insulator body 1 has a sound-guiding groove 4, which is filled with cured sound-guiding adhesive 5. The outer wall of the insulator body 1 is provided with a skirt 7. The upper flange 2 and the lower flange 3 are provided with magnetic coding tracks 6, and the outer wall of the magnetic coding tracks 6 is distributed with a number of magnetic marking points 61.

[0021] In a preferred embodiment, a guide groove is provided on the outer wall of the insulator body 1, and the guide groove is located at the outer edge of the sound-guiding groove 4.

[0022] In a preferred embodiment: the cross-sectional shape of the sound-conducting groove 4 is arc-shaped, the width of the sound-conducting groove 4 is 7mm, and the depth is 2mm; the sound-conducting adhesive 5 is a room temperature vulcanizing silicone rubber material, and the difference between its acoustic impedance and the acoustic impedance of the ceramic material of the insulator body 1 is less than ±10%.

[0023] In a preferred embodiment: the magnetic coding track 6 is installed on the outer wall of the upper flange 2 and the lower flange 3, and the magnetic marking points 61 are embedded and spaced on the magnetic coding track 6, with the central angle between each magnetic marking point 61 being 15°.

[0024] A phased array ultrasonic testing method for magnetic sleeves of post insulators includes the following steps: S1: A flexible phased array probe 8 is fixed inside a magnetic sleeve carrier 9. The magnetic sleeve carrier 9 has an arc-shaped structure and six rolling magnetic wheels 10 are installed on its inner side. S2: Adsorb the magnetic sleeve carrier 9 onto the magnetic coding track 6 so that the working surface of the phased array probe 8 comes into contact with the magnetic coding track 6; S3: The magnetic sleeve carrier 9 moves circumferentially along the magnetic coding track 6. Whenever it passes a magnetic marker point 61, a position trigger signal is generated by the Hall sensor or magnetic encoder, and the phased array ultrasonic system synchronously acquires a frame of ultrasonic echo data. S4: Use full focusing or synthetic aperture focusing to reconstruct images of the acquired multi-frame data to obtain defect images of the interior of the insulator body 1 and the flange bonding interface; S5: Compare the reconstructed image with the preset defect feature library and output the defect type, location and size.

[0025] In a preferred embodiment, both the magnetic sleeve carrier 9 and the magnetic wheel 10 are made of insulating material, so that the entire detection device is suitable for live-line working scenarios and can detect equipment with voltage levels of 110kV and above at a safe distance.

[0026] In a preferred embodiment: the phased array probe 8 has 90 array elements, a center frequency of 8MHz, a linear scanning mode, and a scanning angle range of 0°.

[0027] In a preferred embodiment: In S3, the phased array system acquires a set of full matrix acquisition data at each trigger point. The full matrix acquisition data contains the time domain signals of all transmit and receive array elements, which are used for subsequent full-focus reconstruction.

[0028] In a preferred embodiment: when the insulator body 1 is provided with upper and lower sound-guiding grooves 4, the upper and lower sound-guiding grooves 4 are scanned in sequence, and the data obtained from each scan are spliced ​​and fused according to the axial coordinate to form a three-dimensional ultrasonic test image of the entire insulator body 1.

[0029] In a preferred embodiment, the method further includes cleaning the sound-guiding groove 4 and replenishing the sound-guiding adhesive 5 before testing, and sealing the sound-guiding groove 4 with adhesive after testing.

[0030] In the above structure, when the phased array probe 8 passes over the surface of the acoustic conductive adhesive 5 under the drive of the magnetic sleeve carrier 9, the acoustic impedance of the acoustic conductive adhesive 5 matches that of the insulator body 1, eliminating the ultrasonic total reflection phenomenon caused by the air gap, thereby greatly improving the ultrasonic transmittance, so that the probe can clearly capture the reflected echo of the tiny cracks inside the insulator.

[0031] 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.

[0032] 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 technical solutions and their equivalents.

Claims

1. A post insulator, comprising an insulator body (1), an upper flange (2), and a lower flange (3), characterized in that: The upper flange (2) and the lower flange (3) are respectively installed on the top and bottom of the insulator body (1). The outer wall of the insulator body (1) is provided with a sound-guiding groove (4), and the sound-guiding groove (4) is filled with cured sound-guiding adhesive (5). The outer wall of the insulator body (1) is provided with a skirt (7). The upper flange (2) and the lower flange (3) are provided with magnetic coding tracks (6), and the outer wall of the magnetic coding tracks (6) is distributed with a number of magnetic marking points (61). The cross-sectional shape of the sound-guiding groove (4) is arc-shaped, the width of the sound-guiding groove (4) is 2mm-8mm, and the depth is 1mm-3mm; the sound-guiding adhesive (5) is room temperature vulcanized silicone rubber or epoxy-based ultrasonic coupling material, and the difference between its acoustic impedance and the acoustic impedance of the ceramic material of the insulator body (1) is less than ±10%.

2. A post insulator according to claim 1, characterized in that: The outer wall of the insulator body (1) is provided with a guide groove, which is located at the outer edge of the sound-guiding groove (4).

3. A post insulator according to claim 1, characterized in that: The magnetic coding track (6) is installed on the outer wall of the upper flange (2) and the lower flange (3). The magnetic marking points (61) are embedded and spaced on the magnetic coding track (6), and the central angle between each magnetic marking point (61) is 5°-30°.

4. A phased array ultrasonic testing method for magnetic sleeves of post insulators according to any one of claims 1-3, characterized in that, Includes the following steps: S1: A flexible phased array probe (8) is fixed inside a magnetic sleeve carrier (9). The magnetic sleeve carrier (9) has an arc or C-shaped clamp structure and three to six rollable magnetic wheels (10) are installed on its inner side. S2: Adsorb the magnetic sleeve carrier (9) onto the magnetic coding track (6) so that the working surface of the phased array probe (8) comes into contact with the magnetic coding track (6); S3: Move the magnetic sleeve carrier (9) circumferentially along the magnetic coding track (6). Whenever it passes a magnetic marker point (61), a position trigger signal is generated by the Hall sensor or magnetic encoder, and the phased array ultrasonic system synchronously acquires a frame of ultrasonic echo data. S4: Use full focusing or synthetic aperture focusing to reconstruct images of multiple frames of data to obtain defect images of the insulator body (1) and flange bonding interface; S5: Compare the reconstructed image with the preset defect feature library and output the defect type, location and size.

5. The ultrasonic testing method for a magnetic sleeve phased array according to claim 4, characterized in that: The magnetic sleeve carrier (9) and magnetic wheel (10) are both made of insulating materials or have an insulating covering layer, so that the entire detection device is suitable for live operation scenarios and can detect equipment with voltage levels of 110kV and above at a safe distance.

6. The ultrasonic testing method for a magnetic sleeve phased array according to claim 4, characterized in that: The phased array probe (8) has 16-128 array elements, a center frequency of 2.5 MHz-10 MHz, and uses linear or sector scanning for electronic scanning. The scanning angle range is -30° to +30°.

7. The ultrasonic testing method for a magnetic sleeve phased array according to claim 4, characterized in that: In step S3, the phased array system acquires a set of full matrix acquisition data at each trigger point. The full matrix acquisition data contains the time domain signals of all transmit and receive array elements, which are used for subsequent full focusing reconstruction.

8. The ultrasonic testing method for a magnetic sleeve phased array according to claim 4, characterized in that: When the insulator body (1) is provided with two or more upper and lower sound-guiding grooves (4), each groove is scanned in sequence, and the data obtained from each scan is spliced ​​and fused according to the axial coordinate to form a three-dimensional ultrasonic test image of the entire insulator body (1).

9. The ultrasonic testing method for a magnetic sleeve phased array according to claim 4, characterized in that: It also includes the steps of cleaning the sound-guiding groove (4) and replenishing the sound-guiding adhesive (5) before testing, and the steps of sealing and protecting the sound-guiding groove (4) after testing.

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