Lead seal defect detection method based on phased array ultrasonic detection technology

Abstract

The invention relates to the technical field of nondestructive testing, in particular to a lead seal defect detection method based on a phased array ultrasonic testing technology. The invention discloses a lead seal defect detection method based on a phased array ultrasonic detection technology. The method comprises the following steps: acquiring surface three-dimensional data; carrying out data processing and modeling; phased array ultrasonic detection preparation; performing ultrasonic scanning; data analysis and defect identification; positioning and quantifying defects; and performing evaluation and report generation. According to the method, laser scanning is combined with phased array ultrasound, microscopic and macroscopic characteristics of the surface of the lead seal are obtained through laser scanning, an accurate three-dimensional geometric model is generated, the solid form of the lead seal is reproduced, a visual reference frame is provided for subsequent phased array ultrasound, and self-adaptive frequency adjustment and dynamic focusing control technologies are combined, so that the accuracy of the lead seal is improved. Different areas and heterogeneity of the lead sealing material are identified, the focusing position and depth of the ultrasonic beam are adjusted in real time, and the flexibility and accuracy of defect detection are improved.

Description

Technical Field

[0001] The invention relates to the technical field of nondestructive testing, and in particular to a lead seal defect detection method based on phased array ultrasonic testing technology. Background Art

[0002] Lead seals are key components to ensure the integrity of containers, pipelines and specific structures, and their reliability is directly related to industrial safety and operational continuity. Lead seals that are traditionally made on-site by hand are very likely to cause unexpected stress concentration due to external forces or ambient temperature differences in complex process flows and construction environments, leading to tiny cracks or structural damage. These hidden defects become the source of potential safety hazards. Therefore, efficient and accurate lead seal defect detection is crucial. With the development of technology, phased array ultrasonic detection technology has been introduced into lead seal defect detection. By electronically controlling ultrasonic emission, accurate scanning and imaging of the internal structure of the object being inspected can be achieved, revealing subtle abnormalities in the internal structure.

[0003] However, the existing phased array ultrasonic detection method is single, the three-dimensional reconstruction accuracy of the surface and internal structure is not high, and it is difficult to provide an intuitive and accurate reference model. In addition, when dealing with different materials and structures, it is time-consuming and labor-intensive to manually adjust the detection parameters, which further limits the detection efficiency and quality, resulting in low detection flexibility and accuracy. Therefore, a lead seal defect detection method based on phased array ultrasonic detection technology is needed to solve the above problems. Summary of the invention

[0004] In view of the deficiencies in the prior art, an object of the present invention is to provide a lead seal defect detection method based on phased array ultrasonic detection technology.

[0005] A lead seal defect detection method based on phased array ultrasonic detection technology comprises the following steps:

[0006] (1) Surface 3D data acquisition: Use laser scanning equipment to fully scan the seal surface and capture the 3D geometry of the seal;

[0007] (2) Data processing and modeling: The collected 3D point cloud data is reviewed and marked, noise points are removed, and a detailed surface model is generated to preliminarily identify abnormal or potential defect areas on the seal surface;

[0008] (3) Preparation for phased array ultrasonic testing: Select a suitable phased array ultrasonic probe based on the seal material and expected defect type, and perform strict calibration to ensure that the detection angle and frequency settings are suitable for the target detection area;

[0009] (4) Ultrasonic scanning: Perform refined phased array ultrasonic scanning in the initially predicted defective area of ​​the seal, using phased array ultrasonic technology to deeply detect defects in the internal structure;

[0010] (5) Data analysis and defect identification: The collected ultrasonic images and signal data are used to identify voids, cracks, or other forms of defects based on color differences in the images and known defect characteristics;

[0011] (6) Defect location and quantification: accurately locate the identified defects, record their coordinates in the 3D model, and estimate the size, shape, and severity of the defects;

[0012] (7) Evaluation and report generation: Based on the nature and location of the defects, combined with the safety requirements and usage conditions of the seal, a risk assessment is conducted, and all test data and evaluation results are integrated to prepare a detailed test report, including the test process, description of the defects found, evaluation conclusions and recommended follow-up measures.

[0013] Furthermore, the laser scanning device adopts high-precision multi-beam laser synchronous scanning technology.

[0014] Furthermore, the data processing and modeling also includes constructing 2D graphic models of different slopes using plane drawing software.

[0015] Furthermore, in the data processing and modeling, after a detailed surface model is generated, surface contaminants are observed and physical cleaning is performed as needed.

[0016] Furthermore, the ultrasonic probe is integrated with an automatic coupling agent dispensing system, and a coupling agent made of biodegradable material is used.

[0017] Furthermore, in the preparation for the phased array ultrasonic detection, a phased array ultrasonic module equipped with an adaptive frequency adjustment function is selected.

[0018] Furthermore, the phased array ultrasonic technology includes a dynamic focus control technology, which adjusts the ultrasonic focus position in real time according to the internal structure of the seal.

[0019] Furthermore, during the ultrasonic scanning, the 2D image is imported into the detection instrument, the longitudinal wave wedge is set to 0°, and the scanning offset is adjusted to ensure that the scanned image is consistent with the actual seal structure.

[0020] Furthermore, in the ultrasonic scanning, beam deflection and focusing are achieved through signal delay technology, the obtained scanning waveform uses color to distinguish the amplitude, and the image is generated using phased array imaging technology.

[0021] Furthermore, in the data analysis and defect identification, the surface and internal inspection data are combined for comprehensive analysis, and the BeamTool software is used to perform acoustic beam simulation.

[0022] The beneficial effects achieved by the present invention are as follows: 1. The present invention combines laser scanning with phased array ultrasound to obtain the microscopic and macroscopic features of the lead seal surface through laser scanning, and generates an accurate three-dimensional geometric model to reproduce the physical shape of the lead seal, providing an intuitive reference framework for subsequent phased array ultrasound, and combining it with adaptive frequency adjustment and dynamic focusing control technology to identify different areas of the lead seal material and its heterogeneity, adjust the focusing position and depth of the ultrasonic beam in real time, and automatically optimize the detection parameters as the lead seal material and structure change, thereby improving the flexibility and accuracy of defect detection.

[0023] 2. The present invention combines laser-assisted positioning to quickly identify pollutants and irregular areas on complex surfaces, provide data support for the precise positioning of the ultrasonic probe, and effectively reduce detection blind spots by accurately matching the probe with the target area, thereby improving the accuracy of defect positioning and providing an accurate basis for subsequent maintenance.

[0024] 3. The present invention utilizes the dynamic focusing control technology of phased array ultrasound, combined with professional sound beam simulation software BeamTool, to achieve deep identification and fine classification of tiny defects. The dynamic focusing mechanism enables the ultrasonic beam to maintain the optimal focusing state at different depths, thereby improving the sensitivity and accuracy of detection.

[0025] 4. The present invention generates a detailed report by integrating the test data, performs risk assessment based on the comprehensive test data, and generates a report containing detailed test process, defect characteristics, assessment conclusions and recommended measures, providing a scientific basis for subsequent maintenance and decision-making.

[0026] 5. The present invention uses a phased array ultrasonic module with adaptive frequency adjustment and a biodegradable coupling agent, which not only improves the adaptability to different lead seal materials and structures, but also embodies the concept of environmental protection and promotes the sustainable development of detection technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a schematic flow chart of a lead seal defect detection method based on phased array ultrasonic detection technology adopted in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below in conjunction with specific embodiments.

[0029] In the present invention, unless otherwise specified, the raw materials and equipment used can be purchased from the market or are commonly used in the art. The methods in the following embodiments, unless otherwise specified, are all conventional methods in the art.

[0030] Example: This example is intended to perform nondestructive testing on high-pressure lead seals in oil pipelines to ensure their sealing integrity. The target lead seal has a diameter of about 100 mm, a thickness of about 5 mm, and is made of 99.9% pure lead. The test is intended to detect potential defects such as internal cracks and holes, and the minimum detectable defect size is set to 0.5 mm.

[0031] A lead seal defect detection method based on phased array ultrasonic testing technology, such as Figure 1 As shown, the following steps are included:

[0032] (1) Surface 3D data acquisition

[0033] The Leica ScanStation P50 high-precision laser scanner, equipped with multi-beam laser synchronous scanning technology and set to a high resolution of 0.2mm, performs a comprehensive scan of the seal from 360 degrees around the top and bottom, capturing the three-dimensional geometric shape of the seal, ensuring complete coverage of all surface features of the seal and reducing blind spots caused by occlusion; multi-view data fusion technology is used to enhance the density of point cloud data (≥150 points / square centimeter), and photogrammetry technology is used to capture surface textures, mapping high-definition images to point cloud models to enhance the model's realism and detail recognition capabilities;

[0034] (2) Data processing and modeling

[0035] In the AutoCAD 2022 environment, the Point Cloud Library (PCL) is integrated to denoise and optimize the 3D point cloud data, and a high-precision 3D model of the seal surface is constructed through surface fitting technology. In this process, the software's built-in tools are used to preliminarily analyze the model, mark possible abnormal areas or suspected defect locations, and prepare for subsequent inspections.

[0036] (3) Phased array ultrasonic testing preparation

[0037] Based on the three-dimensional model, the optimal ultrasonic scanning path is generated, taking into account the efficiency and coverage of sound wave propagation to ensure that each potential defect area can be effectively detected; a phased array ultrasonic probe with a frequency range of 2MHz to 10MHz and an adaptive frequency adjustment function is selected, which is suitable for lead materials, equipped with an automatic coupling agent dispensing system, and uses environmentally friendly biodegradable coupling agents to ensure good ultrasonic propagation. The probe is accurately calibrated according to the sound velocity of the lead seal material, and the detection angle range is set to 0° to 70°, and the initial frequency is set to 5MHz to achieve the best balance between penetration and resolution. The subsequent detection process can monitor the ultrasonic echo quality in real time, and dynamically adjust the frequency, power and focus depth according to real-time detection feedback to deal with lead seals of different thicknesses or uneven materials;

[0038] (4) Ultrasound scan

[0039] Using the dynamic focus control of phased array technology, the predicted defect area is deeply scanned according to the preset path. Guided by the 2D graphic model, the most sensitive detection method is selected for different types of defects in combination with longitudinal wave, shear wave and surface wave modes to improve the breadth and depth of defect identification. The beam direction is adjusted through signal delay technology to ensure precise focusing. The resulting image uses different colors to represent different amplitudes to achieve intuitive display of defects. The collected ultrasonic data is used to reconstruct the three-dimensional image of the defect area through inverse scattering technology to achieve stereoscopic observation from macro to micro levels.

[0040] (5) Data analysis and defect identification

[0041] BeamTool software is used to simulate the acoustic beam path, and phased array ultrasonic images and point cloud data are combined for comprehensive analysis. Known defect features are identified based on color differences and waveform features, and thresholds are set to automatically identify voids (color coding below -20dB), cracks (abnormal waveform interruption), etc. An interactive interface is provided so that inspectors can intuitively compare the original 3D model, ultrasonic images and recognition results, and perform necessary manual review and corrections;

[0042] (6) Defect location and quantification

[0043] Adopt higher-precision coordinate measurement technology, such as laser tracker-assisted positioning, to improve coordinate accuracy to ±0.05mm, mark the exact position of each defect in the 3D model, ensure the defect position to ±0.1mm accuracy, and pass the defect echo amplitude, waveform change and other parameters; establish a defect quantification model based on physical principles, consider material attenuation, scattering effect and other characteristics, and more accurately estimate the defect size, shape and severity, with the error range controlled within ±5%;

[0044] (7) Evaluation and report generation

[0045] With reference to standards such as ASME SEC V and ASTM E270, combined with lead seal safety specifications, the risks brought by defects are evaluated, a risk prediction model based on historical data is introduced, the possibility of defect development and potential hazards are evaluated, and preventive maintenance suggestions are put forward; the inspection process, equipment parameters used, list of defects found (including location, size, type), risk level and recommended repair measures are recorded in detail, and a detailed inspection report is compiled; an interactive electronic report containing dynamic 3D models, ultrasonic image sequences and detailed analysis results can be generated to facilitate online browsing, query and sharing, thereby improving the practical value and communication efficiency of the report.

[0046] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A lead seal defect detection method based on phased array ultrasonic detection technology, characterized in that: The following steps are involved: (1) Surface 3D data acquisition: Use laser scanning equipment to fully scan the seal surface and capture the 3D geometry of the seal; (2) Data processing and modeling: The collected 3D point cloud data is reviewed and marked, noise points are removed, and a detailed surface model is generated to preliminarily identify abnormal or potential defect areas on the seal surface; (3) Preparation for phased array ultrasonic testing: Select a suitable phased array ultrasonic probe based on the seal material and expected defect type, and perform strict calibration to ensure that the detection angle and frequency settings are suitable for the target detection area; (4) Ultrasonic scanning: Perform refined phased array ultrasonic scanning in the initially predicted defective area of ​​the seal, using phased array ultrasonic technology to deeply detect defects in the internal structure; (5) Data analysis and defect identification: The collected ultrasonic images and signal data are used to identify cavities, cracks, or other forms of defects based on color differences in the images and known defect characteristics; (6) Defect location and quantification: accurately locate the identified defects, record their coordinates in the 3D model, and estimate the size, shape, and severity of the defects; (7) Evaluation and report generation: Based on the nature and location of the defects, combined with the safety requirements and usage conditions of the seal, a risk assessment is conducted, and all test data and evaluation results are integrated to prepare a detailed test report, including the test process, description of the defects found, evaluation conclusions and recommended follow-up measures.

2. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: The laser scanning device adopts high-precision multi-beam laser synchronous scanning technology.

3. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: The data processing and modeling also includes constructing 2D graphic models of different slopes using plane drawing software.

4. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: In the data processing and modeling, after a detailed surface model is generated, surface contaminants are observed and physical cleaning is performed as needed.

5. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: The ultrasonic probe is integrated with an automatic coupling agent dispensing system, and a coupling agent made of biodegradable material is used.

6. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: In the phased array ultrasonic testing preparation, a phased array ultrasonic module equipped with an adaptive frequency adjustment function is selected.

7. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: The phased array ultrasonic technology includes a dynamic focus control technology, which adjusts the ultrasonic focus position in real time according to the internal structure of the seal.

8. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: During the ultrasonic scanning, the 2D image is imported into the detection instrument, the longitudinal wave wedge is set to 0°, and the scanning offset is adjusted to ensure that the scanned image is consistent with the actual seal structure.

9. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: In the ultrasonic scanning, beam deflection and focusing are achieved through signal delay technology, the obtained scanning waveform uses color to distinguish high and low amplitudes, and the image is generated using phased array imaging technology.

10. The lead seal defect detection method based on phased array ultrasonic detection technology according to claim 1 is characterized in that: In the data analysis and defect identification, the surface and internal inspection data are combined for comprehensive analysis, and the BeamTool software is used to perform acoustic beam simulation.

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