A modular array element piezoelectric ceramic ultrasonic guided wave detection device and detection method

Abstract

The present invention discloses a modular array element piezoelectric ceramic ultrasonic guided wave detection device and a detection method. The device includes an array element module and a fastening component; the array element module contains a group of excitation sensors and receiving sensors, and the number of array element modules can be freely combined according to the detection needs, and several array element modules are fixed on the outer wall of the pipeline to be detected through the fastening component. The signal wire harness of each array element module is connected to the signal sensing and signal processing system, and the time delay of each array element channel of the focusing signal is calculated through the time delay of each array element channel of the primary echo signal, so as to realize the focusing of the guided wave signal. The device of the present invention has a flexible structural configuration and a high customization degree, can quickly adjust the installation configuration according to different detection needs, and is applicable to pipelines with different large diameters.

Description

Technical Field

[0001] The present invention relates to the technical field of nondestructive testing, and in particular to a pipeline structure damage detection device and a detection method. Background Art

[0002] With the advancement of urbanization construction in China and the establishment of a green, low-carbon and circular development economic system, the pipe network system, as an important part of China's economic construction, is also expanding in scale, which brings huge challenges to the structural health monitoring of the pipeline system. The ultrasonic guided wave nondestructive testing technology is a long-distance and large-scale structure rapid scanning technology, which has the advantages of single-point excitation at a time, full cross-section coverage detection, long detection distance, high detection efficiency, etc., and has been widely used in the detection of engineering structures such as pipe fittings, rods, thin plates, and tracks.

[0003] The single-channel signal of traditional ultrasonic guided wave detection cannot achieve directional control of guided wave propagation, and can only excite guided waves with a specific energy magnitude and mode in the circumferential direction without discrimination, resulting in poor characterization ability for small defects and being unable to adapt to the situation of small defects and complex defect distributions. The phased ultrasonic guided wave detection technology is a new detection technology developed on the basis of the original single-channel ultrasonic guided wave detection technology by referring to the traditional phased ultrasonic detection technology. By controlling the delay and amplitude parameters of each array element of the array transducer and the phased excitation of the guided wave field, functions such as beam focusing, frequency scanning, and mode scanning can be achieved, while improving the resolution of defect detection and the success rate of defect identification, and greatly improving the adaptability of pipeline detection.

[0004] At present, the commercially available multi-channel guided wave phased array systems in the market are expensive, and the hardware and software of the equipment are highly integrated. It is difficult to flexibly increase or decrease the detection array elements to adapt to pipelines of different diameters, and it is difficult to meet the customized needs of users. In different use environments, the detection accuracy and detection efficiency are greatly reduced. Summary of the Invention

[0005] In order to solve the deficiencies of the prior art and achieve the purpose of high-sensitivity, fast, and accurate active detection of the pipeline structure, the present invention adopts the following technical solutions:

[0006] A modular array element piezoelectric ceramic ultrasonic guided wave detection device includes a group of array element modules and a fastening component. The array element module includes a housing, a signal wire harness, and a pair of piezoelectric ceramics with the telescopic direction consistent with the axial direction of the pipeline. The piezoelectric ceramics include an excitation sensor and a receiving sensor. The excitation sensor and the receiving sensor are embedded in the bottom surface of the housing and are respectively connected to the signal wire harness, so as to isolate the influence of the external environment and ensure the reliability and stability of the device and the signal. The array element modules are circumferentially and evenly arranged on the outer wall of the pipeline and are connected in series and spliced by the fastening component. Different modes of ultrasonic guided waves to be excited and different requirements for focusing ultrasonic guided waves can be generated by adjusting the number and arrangement spacing of the array element modules.

[0007] The modular and selectable array elements greatly improve the flexibility for installation on different pipe diameters and are applicable to pipes with different diameters. This detection device combines the phased array element focusing technology and the ultrasonic guided wave detection technology that can cover the entire guided wave structure at one time, realizes the focusing of guided wave energy at any position in the circumferential direction of the pipeline, and can perform high-sensitivity, fast, and accurate active detection on the pipeline structure.

[0008] Further, among a group of the array element modules, there is a No. 0 module provided with a fastening ratchet wheel. One end of the fastening component is connected to the No. 0 module. After covering the array element module, the other end is cooperatively arranged with the fastening ratchet wheel. By rotating the fastening ratchet wheel to tighten the fastening component, each array element module can be closely attached to the outer wall of the pipeline, ensuring the stability of the detection device and preventing loosening.

[0009] Further, the fastening component includes a flexible organic material fabric and a flexible rack. The array element module is surrounded and wrapped by the flexible organic material fabric to make the array element module close to the pipeline. The flexible rack is cooperatively arranged with the fastening ratchet wheel. By rotating the fastening ratchet wheel to tighten the fastening component.

[0010] Further, mounting lugs are provided on the upper part of the array element module for inserting the fastening component, facilitating the installation of the fastening component and the fixation of the positions of each array element module after installation, and preventing displacement in the axial direction of the pipeline.

[0011] Further, the signal wire harness includes an excitation signal wire harness and a receiving signal wire harness, which are led out through a cable with a shielding layer and are respectively connected to the signal sensing and signal processing system.

[0012] Further, an ultrasonic coupling agent is coated between the array element module and the outer wall of the pipeline. The excitation sensor and the receiving sensor are in contact with the outer wall of the pipeline through the ultrasonic coupling agent to ensure the maximization of the energy conversion efficiency.

[0013] A modular array element piezoelectric ceramic ultrasonic guided wave detection method uses a set of array element modules evenly arranged circumferentially on the outer wall of the pipeline. The array element module includes a pair of piezoelectric ceramics with the telescopic direction consistent with the axial direction of the pipeline, namely an excitation sensor and a receiving sensor. The detection method includes the following steps:

[0014] S1. According to the calculation of the guided wave dispersion characteristics of the pipeline to be detected, select the guided wave excitation parameters;

[0015] S2. Primary signal excitation. The signal sensing and signal processing system inputs the first signal to a set of array element modules. The ultrasonic guided wave excited by the excitation sensor scans along the pipeline;

[0016] S3. Primary signal acquisition. When the ultrasonic guided wave encounters a defect, a reflected echo is generated. The receiving sensor collects the ultrasonic guided wave echo generated by the primary signal excitation and transmits the data to the signal sensing and signal processing system;

[0017] S4. Primary signal time reversal processing. The signal sensing and signal processing system filters the acquired primary reflection signal by using the variational mode decomposition method and performs time reversal processing on the filtered signal;

[0018] S5. Secondary signal excitation. The signal after the primary signal time reversal processing is reloaded on this set of array element modules for guided wave focusing;

[0019] S6. Secondary signal acquisition. The receiving sensor collects the ultrasonic guided wave echo generated by the secondary signal excitation and transmits the data to the signal sensing and signal processing system to complete the defect detection or structural health monitoring of the pipeline.

[0020] Further, the specific content of step S1 is to calculate the dispersion curve of the guided wave L mode according to the geometric dimensions and material mechanics parameters of the pipeline to be measured, and select the guided wave excitation parameters.

[0021] Further, in step S2, the signal sensing and signal processing system controls all channels of the multi-channel signal generator to generate consistent signals with a certain frequency. After being amplified by the multi-channel power amplifier, the signals are applied to the excitation sensor to excite the first non-focused ultrasonic guided wave of the L mode. The excited ultrasonic guided wave propagates along the axial direction of the pipeline; in step S4, the signal sensing and signal processing system applies a time reversal window to the signal, intercepts the defect wave packet with the same duration as the primary excitation signal for the filtered signal, applies a time reversal window to it, and normalizes the signal amplitude of each channel.

[0022] Further, the guided wave focusing in step S5 is to load the signal after time reversal processing to the corresponding channels of the primary signal acquisition. Due to the reciprocity of the waveguide medium, the time-delay signals are excited respectively in each channel, and the guided wave energy is focused at the defect.

[0023] The advantages and beneficial effects of the present invention are as follows:

[0024] The device of the present invention reduces the installation difficulty by means of an adjustable array element module and a method of tensioning with a fastening component, improves the applicability of the detection device to different pipe diameters, can make flexible adjustments according to the on-site detection environment and requirements, and greatly improves the customization ability; it can generate multi-channel excitation guided wave signals, and can achieve the focusing of guided wave energy at any position in the circumferential direction of the pipe, improving the detection efficiency of microstructural damage experiments in pipe detection and obtaining more defect echo information.

[0025] Using the signal processing and recognition method of the present invention, the echo signal can be accurately recognized and judged, with high sensitivity, fast response, simple operation and low cost. Description of the Drawings

[0026] Figure 1 It is a schematic diagram of the polarization direction of the piezoelectric ceramics of the present invention.

[0027] Figure 2 It is a schematic diagram of the arrangement direction of the piezoelectric ceramic excitation phased array and the piezoelectric ceramic receiving array of the present invention.

[0028] Figure 3 It is a schematic diagram of the installation of the detection device of the present invention.

[0029] Figure 4 It is a schematic diagram of the component composition of the detection device of the present invention

[0030] Figure 5 It is a schematic diagram of the array mode of the array element module of the present invention.

[0031] Figure 6 It is a perspective view of the side structure of the No. 0 module of the present invention.

[0032] Figure 7 It is a schematic diagram of the structure of the fastening component of the present invention.

[0033] Figure 8 It is a schematic diagram of the connection between the array element module and the signal sensing and signal processing system of the present invention.

[0034] In the figure: 1. Array element module; 11. Housing; 12. Signal wire harness; 13. Receiving sensor; 14. Excitation sensor; 15. No. 0 module; 151. Fastening ratchet wheel; 2. Fastening component; 21. Flexible rack; 22. Flexible organic material fabric; 3. Pipe. Detailed Embodiments

[0035] The following is a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not used to limit the present invention.

[0036] As Figure 1-3 shown, a modular array element piezoelectric ceramic ultrasonic guided wave detection device includes an array element module 1 and a fastening assembly 2. The array element modules 1 are uniformly arranged on the outer wall of a pipeline 3 according to the detection requirements, and an ultrasonic coupling agent is applied thereto.

[0037] As Figure 4 shown, a phased array of modularly installed piezoelectric ceramic sensors. Each array element module 1 includes a pair of piezoelectric ceramics that expand and contract along the length direction, and the expansion and contraction direction is consistent with the axial direction of the pipeline, namely an excitation sensor 14 and a receiving sensor 13 respectively. The excitation sensor 14 is responsible for exciting ultrasonic guided wave signals, and the receiving sensor 13 is responsible for transmitting back the reflected signals. The excitation sensor 14 and the receiving sensor 13 are in contact with the outer wall of the pipeline 3 through the coupling agent to maximize the energy conversion efficiency; each pair of sensors is embedded in a housing 11 made of an organic material and is respectively connected to a signal wire harness 12 to isolate the influence of the external environment and ensure the reliability and stability of the device and the signal.

[0038] As Figure 5-7 shown, the fastening assembly 2 passes through the lugs of each array element module 1, and the entire device is tightened by rotating the fastening ratchet wheel 151 on the zero module 15, so that each array element module 1 can be closely attached to the pipeline 3. Different modes of ultrasonic guided waves to be excited and different requirements for focusing ultrasonic guided waves can be generated by adjusting the number of array element modules 1 and the arrangement spacing.

[0039] As Figure 8 shown, the signal wire harness 12 on the array element module 1 includes an excitation signal wire harness and a receiving signal wire harness, which is led out through a cable with a shielding layer and is connected to the signal sensing and signal processing system.

[0040] The signal sensing and signal processing system has functions including: calculating the guided wave dispersion curve of the pipeline to be measured, controlling the excitation states of the channels of the multi-channel signal generator, receiving the signals of the ultrasonic guided wave receiving sensors, filtering and inverting the signals, re-exciting and focusing the signals, etc.

[0041] On the basis of the above technical solutions, the present invention further discloses a method for detecting a pipeline based on time reversal focusing ultrasonic guided waves, including:

[0042] (1) According to the diameter of the pipeline to be measured and the requirements of detection accuracy, a certain number of array element modules 1 are selected. The fastening component 2 passes through the lugs of each array element module 1, and the entire device is tightened by rotating the fastening ratchet wheel 151 on the zero module 15, so that each array element module 1 can closely fit the pipeline 3. The signal wire harness 12 on each array element module 1, including the excitation signal wire harness and the received signal wire harness, is led out through a cable with a shielding layer and connected to each channel of the signal sensing and signal processing system.

[0043] (2) Primary signal excitation. The computer controls all channels of the multi-channel signal generator to generate consistent signals of a certain frequency. After being amplified by the multi-channel power amplifier, the signals are applied to the piezoelectric ceramic ultrasonic guided wave excitation phased array element excitation sensor 14 to excite the first non-focused ultrasonic guided wave of the L mode. The excited ultrasonic guided wave propagates along the axial direction of the pipeline.

[0044] (3) Primary signal acquisition. When the ultrasonic guided wave encounters a defect, a reflected echo is generated and captured by the piezoelectric ceramic ultrasonic guided wave receiving array element receiving sensor 13. The multi-array element received data enters the computer through the multi-channel signal acquisition card for filtering processing.

[0045] (4) Apply a time reversal window to the signal. The signal is filtered by variational mode decomposition, and the filtered signal is intercepted to obtain a defect wave packet equivalent to the duration of the primary excitation signal. Finally, a time reversal window is applied to it and the amplitude of each channel signal is normalized.

[0046] (5) Secondary signal excitation. The computer loads the time-reversed signal to the corresponding channels of the primary signal acquisition. Due to the reciprocity of the waveguide medium, the time-delay signals are excited separately in each channel, and the guided wave energy is focused at the defect.

[0047] (6) Secondary signal acquisition. The same as the third step. The defect detection or structural health monitoring of the pipeline is completed.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A modular array element piezoelectric ceramic ultrasonic guided wave detection device, comprising a group of array element modules (1) and a fastening assembly (2). Characterized in that: The array element module (1) includes a housing (11), a signal wire harness (12), and a pair of piezoelectric ceramics with a telescopic direction consistent with the axial direction of the pipeline (3). The piezoelectric ceramics include an excitation sensor (14) and a receiving sensor (13). The excitation sensor (14) and the receiving sensor (13) are embedded in the bottom surface of the housing (11) and are respectively connected to the signal wire harness (12). The array element modules (1) are circumferentially and uniformly arranged on the outer wall of the pipeline (3) and are connected in series and spliced by the fastening assembly (2). One group of the array element modules (1) includes a zero module (15) provided with a fastening ratchet wheel (151). One end of the fastening assembly (2) is connected to the zero module (15). After covering the array element module (1), the other end is cooperatively arranged with the fastening ratchet wheel (151), and the fastening assembly (2) is tightened by rotating the fastening ratchet wheel (151). The fastening assembly (2) includes a flexible organic material fabric (22) and a flexible rack (21). The flexible organic material fabric (22) surrounds and wraps the array element module (1). The flexible rack (21) is cooperatively arranged with the fastening ratchet wheel (151), and the fastening assembly (2) is tightened by rotating the fastening ratchet wheel (151). The upper part of the array element module (1) is provided with mounting lugs for inserting the fastening assembly (2).

2. A modular array element piezoelectric ceramic ultrasonic guided wave detection device according to claim 1, Characterized in that The signal wire harness (12) includes an excitation signal wire harness and a receiving signal wire harness, which are led out through a cable with a shielding layer and are respectively connected to a signal sensing and signal processing system.

3. A modular array element piezoelectric ceramic ultrasonic guided wave detection device according to claim 1, Characterized in that An ultrasonic coupling agent is applied between the array element module (1) and the outer wall of the pipeline (3). The excitation sensor (14) and the receiving sensor (13) are in contact with the outer wall of the pipeline (3) through the ultrasonic coupling agent.

4. A modular array element piezoelectric ceramic ultrasonic guided wave detection method, Characterized in that, Based on a modular array element piezoelectric ceramic ultrasonic guided wave detection device according to claim 1, a group of array element modules (1) circumferentially and uniformly arranged on the outer wall of the pipeline (3) are adopted. The array element module (1) includes a pair of piezoelectric ceramics with a telescopic direction consistent with the axial direction of the pipeline (3), namely an excitation sensor (14) and a receiving sensor (13). The detection method includes the following steps: S1. According to the calculation of the guided wave dispersion characteristics of the pipeline (3) to be detected, select the guided wave excitation parameters. S2. Primary signal excitation. The signal sensing and signal processing system inputs a first signal to a group of array element modules (1). The ultrasonic guided wave excited by the excitation sensor (14) scans along the pipeline (3). S3. Primary signal acquisition. The receiving sensor (13) acquires the ultrasonic guided wave echo generated by the primary signal excitation and transmits the data to the signal sensing and signal processing system. S4. Inverse time processing of the primary signal. The signal sensing and signal processing system filters the acquired primary reflection signal using the variational mode decomposition method and performs time reversal processing on the filtered signal. S5. Secondary signal excitation. The signal after the inverse time processing of the primary signal is reloaded onto the array element module (1) to perform guided wave focusing. S6. Secondary signal acquisition. The receiving sensor (13) acquires the ultrasonic guided wave echo generated by the secondary signal excitation and transmits the data to the signal sensing and signal processing system.

5. A modular array element piezoelectric ceramic ultrasonic guided wave detection method according to claim 4, characterized in that the specific content of step S1 is to calculate the dispersion curve of the guided wave L mode according to the geometric dimensions and material mechanics parameters of the pipeline to be measured (3) and select the guided wave excitation parameters.

6. A modular array element piezoelectric ceramic ultrasonic guided wave detection method according to claim 4, characterized in that in step S2, the signal sensing and signal processing system controls all channels of the multi-channel signal generator to generate consistent signals of a certain frequency. After being amplified by the multi-channel power amplifier, the signals are applied to the excitation sensor (14) to excite the first non-focused ultrasonic guided wave of the L mode. The excited ultrasonic guided wave propagates along the axial direction of the pipeline. In step S4, the signal sensing and signal processing system applies a time reversal window to the signal, intercepts the defect wave packet whose duration is equal to that of the primary excitation signal from the filtered signal, applies a time reversal window to it, and normalizes the signal amplitude of each channel.

7. A modular array element piezoelectric ceramic ultrasonic guided wave detection method according to claim 6, characterized in that for the guided wave focusing in step S5, the signal after the time reversal processing is loaded into the corresponding channels of the primary signal acquisition. Due to the reciprocity of the waveguide medium, the time-delay signals are respectively excited in each channel, and the guided wave energy is focused at the defect.

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