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TOFD Echo Signal Processing to Achieve Superresolution
Russian Journal of Nondestructive Testing, 2021It is proposed to use the method of maximum entropy (ME) and the method for constructing the AR model of the TOFD echo spectrum together with the method of splitting the spectrum to increase its resolution and, consequently, information content. The effectiveness of the approach proposed is demonstrated in model experiments. As a result, the resolution
exaly +2 more sources
TOFD Image Features Recognition Based on Improved YOLOv8
2024 IEEE 19th Conference on Industrial Electronics and Applications (ICIEA)TOFD detection is critical to weld quality. TOFD image evaluation is highly labour-intensive, with low efficiency and unstable quality. In order to realize the intelligent recognition of TOFD image features, this study first introduced a self-adaptive ...
Xukai Ren +4 more
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An alternative Ultrasonic Time of Flight Diffraction (TOFD) method
NDT and E International, 2018Abstract In this work an alternative TOFD method is presented, capable to detect and size defects in the inspected material with good precision. It was shown that the diffraction used in this technique is the most relevant signal among the longitudinal backwall and the shear backwall echoes, compared to other TOFD methods.
Thomas G R Clarke
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Shear-wave time of flight diffraction (S-TOFD) technique
NDT and E International, 2006Ultrasonic time of flight diffraction (TOFD) for sizing defects is based on the time of flight of the diffracted echo that is generated when a longitudinal wave is incident on a crack tip. This technique has the limitation during near-surface inspection due to signal superposition.
Krishnan Balasubramaniam +1 more
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Ultrasonic TOFD Detection by Finite Element Simulation Method
Applied Mechanics and Materials, 2014This paper investigated the ultrasonic mechanism of Time of Flight Diffraction (TOFD) by finite element analysis for the better applications of ultrasonic TOFD (Time of Flight Diffraction) detection technology. The welding steel plate with the artificial defects is used in the finite element analysis model.
Han Xin Chen, Shi Qi Yang
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High-Frequency Filtering of Wedge Materials for TOFD
Materials Evaluation, 2023This article addresses the question: What effects do different types of wedge materials have, if any, on frequency filtering in high-frequency time of flight diffraction scanning?
J. Ellis
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Weld crack testing method using ultrasonic TOFD technique
Insight: Non-Destructive Testing and Condition Monitoring, 2010In this paper, both the forward and inverse problems of crack testing using the ultrasonic time-of-flight diffraction (TOFD) B-scan mode are studied. For the forward problem, the propagation behaviour of the ultrasonic beam is described and the electrical and electromechanical elements of the inspection system are characterised using a system ...
Chi Dazhao +3 more
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Immersion and TOFD (I-TOFD): A Novel Combination for Examination of Lower Thicknesses
Journal of Nondestructive Evaluation, 2011Time of flight diffraction (TOFD) is a well-developed ultrasonic non-destructive testing (NDT) technique which has been applied successfully for accurate sizing of defects in thick sections. Codes of practice such as ASME now permit TOFD for routine examination as an alternative to radiography for thick weldments.
R. Subbaratnam +3 more
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Corrected Mode-Converted Wave Method for Detecting Defects in TOFD Dead Zone
Journal of Nondestructive Evaluation, 2023S. Jin +3 more
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Research on the Wall-Climbing Robot of TOFD Inspection for Welding Seam of Spherical Tank
International Conference on Robotics, Intelligent Control and Artificial Intelligence, 2023Spherical tank is a kind of steel pressure vessel, widely used in petroleum, liquefied natural gas and other material storage, its body is composed of a plurality of spherical shell plate after welding, and the welding quality of the spherical shell ...
Xingji Du +4 more
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