Ultrasonic Guided Wave Inspection of Rail Defects Under Shelling

2009 ◽  
Author(s):  
Thomas Hay ◽  
Subash Jayaraman ◽  
Robert Hay
Keyword(s):  
Guided Wave ◽  
Ultrasonic Guided Wave

Ultrasonic unilateral double-position excitation lamb wave defect detection and quantification method for ground electrode of transmission tower

2021 ◽  
pp. 1-15
Author(s):  
Kuan Ye ◽  
Kai Zhou ◽  
Ren Zhigang ◽  
Ruizhe Zhang ◽  
Chunsheng Li ◽  
...  
Keyword(s):  
Guided Waves ◽  
Power Transmission ◽  
Geometric Model ◽  
Guided Wave ◽  
Quantization Error ◽  
Dispersion Function ◽  
Stable Operation ◽  
Transmission Tower ◽  
Ultrasonic Guided Wave ◽  
Transmission Towers

The power transmission tower’s ground electrode defect will affect its normal current dispersion function and threaten the power system’s safe and stable operation and even personal safety. Aiming at the problem that the buried grounding grid is difficult to be detected, this paper proposes a method for identifying the ground electrode defects of transmission towers based on single-side multi-point excited ultrasonic guided waves. The geometric model, ultrasonic excitation model, and physical model are established, and the feasibility of ultrasonic guided wave detection is verified through the simulation and experiment. In actual inspection, it is equally important to determine the specific location of the defect. Therefore, a multi-point excitation method is proposed to determine the defect’s actual position by combining the ultrasonic guided wave signals at different excitation positions. Besides, the precise quantification of flat steel grounding electrode defects is achieved through the feature extraction-neural network method. Field test results show that, compared with the commercial double-sided excitation transducer, the single-sided excitation transducer proposed in this paper has a lower defect quantization error in defect quantification. The average quantization error is reduced by approximately 76%.

scholarly journals Phase-delayed laser diode array allows ultrasonic guided wave mode selection and tuning

2013 ◽  
Vol 113 (14) ◽  
pp. 144904 ◽  
Author(s):  
Pasi Karppinen ◽  
Ari Salmi ◽  
Petro Moilanen ◽  
Timo Karppinen ◽  
Zuomin Zhao ◽  
...  
Keyword(s):  
Laser Diode ◽  
Mode Selection ◽  
Wave Mode ◽  
Guided Wave ◽  
Diode Array ◽  
Laser Diode Array ◽  
Ultrasonic Guided Wave

scholarly journals Rail Diagnostics Based on Ultrasonic Guided Waves: An Overview

2021 ◽  
Vol 11 (3) ◽  
pp. 1071
Author(s):  
Davide Bombarda ◽  
Giorgio Matteo Vitetta ◽  
Giovanni Ferrante
Keyword(s):  
Guided Waves ◽  
Structural Integrity ◽  
Diagnostic Procedures ◽  
Guided Wave ◽  
Rolling Stock ◽  
Technical Literature ◽  
Track Maintenance ◽  
Rail Network ◽  
Ultrasonic Guided Wave ◽  
Maintenance And Inspection

Rail tracks undergo massive stresses that can affect their structural integrity and produce rail breakage. The last phenomenon represents a serious concern for railway management authorities, since it may cause derailments and, consequently, losses of rolling stock material and lives. Therefore, the activities of track maintenance and inspection are of paramount importance. In recent years, the use of various technologies for monitoring rails and the detection of their defects has been investigated; however, despite the important progresses in this field, substantial research efforts are still required to achieve higher scanning speeds and improve the reliability of diagnostic procedures. It is expected that, in the near future, an important role in track maintenance and inspection will be played by the ultrasonic guided wave technology. In this manuscript, its use in rail track monitoring is investigated in detail; moreover, both of the main strategies investigated in the technical literature are taken into consideration. The first strategy consists of the installation of the monitoring instrumentation on board a moving test vehicle that scans the track below while running. The second strategy, instead, is based on distributing the instrumentation throughout the entire rail network, so that continuous monitoring in quasi-real-time can be obtained. In our analysis of the proposed solutions, the prototypes and the employed methods are described.

scholarly journals Plate-like structure damage location identification based on Lamb wave baseline-free probability imaging method

2017 ◽  
Vol 9 (1) ◽  
pp. 168781401668570 ◽  
Author(s):  
Dongsheng Li ◽  
Zihao Jing ◽  
Mengdao Jin
Keyword(s):  
Lamb Wave ◽  
Time Window ◽  
Free Probability ◽  
Structural Response ◽  
Guided Wave ◽  
Time Of Arrival ◽  
Imaging Method ◽  
Detection Techniques ◽  
Damage Location ◽  
Ultrasonic Guided Wave

Damage-scattering signal extraction using conventional ultrasonic guided wave–based damage detection techniques requires the measurement of baseline data under pristine condition. This study proposes a baseline-free ultrasonic guided wave damage localization and imaging method based on Lamb wave baseline-free probability imaging method. Although traditional Lamb wave probability imaging can monitor damage location in plate-like structures, the absolute time of arrival and magnitude of the signal are affected by several factors and are therefore difficult to obtain. This study also proposes a probability-based hyperbola diagnostic imaging method that is based on different times of arrival and has no magnitude information. A distributed active sensor network conforming to a pulse-echo configuration and time window functions is developed to separate damage-scattering signals from structural response signals. Continuous wavelet transform is used to calculate the time of flight of damage signal waves. The numerical simulation and experiments validate the effectiveness of the proposed method in identifying damage.

Storage Tank Floor and Wall Defect In-Situ Inspection With Ultrasonic Guided Wave Technique

2010 ◽  
Author(s):  
Zhanjun Feng ◽  
Weibin Wang ◽  
Wenqiang Tong ◽  
Keyi Yuan ◽  
Zandong Han ◽  
...  
Keyword(s):  
Storage Tank ◽  
Guided Waves ◽  
Ultrasonic Signal ◽  
Guided Wave ◽  
Tank Wall ◽  
Transmission Tomography ◽  
Wall Defect ◽  
Oil Storage ◽  
Ultrasonic Guided Wave

Large storage tanks for oil storage are widely used in petrochemical industry. Corrosion in the tank floor and wall is a serious threat for environmental and economic safety. Owing to their unique potential for long-range, in-plane propagation through plates, Ultrasonic Guided Waves (UGW) offer an obvious solution in the development of an on-board structural health-monitoring (SHM) system, providing assessment of structural integrity for storage tank floor and wall defect in-situ inspection. This paper presents this application by focusing on their propagation through the plate structure. Even very small mechanical discontinuity or geometry change of plate structure, e.g. corrosion defect on tank floor, will influence the propagation characteristic of the guided waves. These effects are measured as mode changes, frequency shifts or filtering, reflection and diffraction of new ultrasonic modes or overall distortion of the original ultrasonic signals. By capturing and analyzing these changes we can deduct the corrosion defect of the tank floor and wall which causes the ultrasonic signal change and interactions. The T/R transducers are required to be attached on the outer edge of the tank floor and outer surface of the tank wall. The technique is developed based on the Lamb wave transmission tomography. Starting from the dispersion curve and choosing the appropriate wave mode, the propagation of the guided waves in the tank floor and wall has been carried out through numerical simulation and the experiment has been conducted for verification using the full-size oil storage tank. The low frequency guided waves can propagate longer distance in planar and tubular structures. The later has been already used in pipeline inspection. The complexity of the application of ultrasonic guided wave in tank floor inspection lies in the object containing multiple lap joint welds along the large diameter of the tank (up to 100 m) and the complicated reconstruction of the two-dimensional defect distribution information. The main scope of the investigation was the application of the ultrasonic transmission tomography for localization of non-uniformities of inside tank floor, taking into account ultrasonic signal losses due to the loading with oil on the top and ground support at the bottom for the tank floor, and the loading with oil inside for the vertical tank wall.

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