A review on non-destructive evaluation of rails: State-of-the-art and future development

Abstract

Rails are systematically inspected for internal and surface defects using various non-destructive evaluation (NDE) techniques. During the manufacturing process, rails are inspected using automated optical cameras and eddy current sensing systems for any surface damage, while the presence of internal defects is assessed through ultrasonic inspection. Similarly, ultrasonic transducers and magnetic induction sensors have been extensively used by the rail industry for the inspection of rails in-service. More recently, automated vision techniques and hybrid systems based on the simultaneous use of pulsed eddy current probes and conventional ultrasonic probes have been introduced for the high-speed inspection of rail tracks. Other NDE techniques, such as electromagnetic acoustic transducers, laser ultrasonics, guided waves, and alternating current field measurement probes, are also under development for application in the rail industry. This paper comprehensively reviews NDE methodologies in use around Europe and North America for rail defect detection. This includes a detailed overview of the background theory and the techniques used to incorporate condition data into maintenance procedures. It also presents a review of the current state-of-the-art in NDE of railways coupled with a discussion of future developments and novel inspection methodologies in the field.

A novel application of image processing for the detection of rail surface RCF damage and incorporation in a crack growth model

“…As expected the largest Mode I SIF is calculated with a 90º crack angle. (2) where: ʚ is nominal stress component, : mode-II SIF, ′ is the shear modulus, is crack major semi axis, is minor semi axis of crack, = √ 2 − 2 . The estimated mode II SIF for different crack inclination angles and axle loads is presented in Figure 12.…”

“…To achieve this, manual inspection of rail defects should be replaced by more efficient non-destructive evaluation (NDE) techniques using visual cameras, ultrasonic probes, eddy currents etc. Papaelias et al [2] mentioned that the high-speed inspection of rails can be achieved with automated vision techniques and hybrid systems based on the simultaneous use of pulsed eddy current probes and conventional ultrasonic probes. Eddy current methods employ techniques such as Field Gradient Imaging, Alternating Current Field Measurement (ACFM), and Electromagnetic Acoustic Transducers (EMATs).…”

A new cracks detection device for magnetic steels

“…The Non Destructive Evaluation (NDE) methods that have been extensively used by the rail industry for surface inspection of rail tracks and wheels and detection of any surface defects/cracks are visual examination (by trained personnel or by automated optical cameras) [4] and magnetic induction techniques (like eddy current sensing systems) [4][5][6]. Similarly, ultrasonic wave * e-mail: manios@ims.demokritos.gr (corresponding author) techniques [4,6] have been extensively used for the detection of internal defects/cracks.…”

“…Similarly, ultrasonic wave * e-mail: manios@ims.demokritos.gr (corresponding author) techniques [4,6] have been extensively used for the detection of internal defects/cracks. Other, more recent NDE methods, are electromagnetic acoustic transducers [4], laser ultrasonics [4], ultrasonic guided waves [3,4,7], wavelet packet decomposition [2], and alternating current field measurement (ACFM) probes [4].…”

Thresholding Based on Maximum Weighted Object Correlation for Rail Defect Detection

“…To efficiently detect such defects, inspection systems based on computer vision have been attracting more and more attention [1], [2]. These systems capture rail surface images with a high-speed line-scan digital camera and automatically inspect the images using a customized image processing software.…”