Numerical Study and Optimal Design of the Butterfly Coil EMAT for Signal Amplitude Enhancement

The global reliance on oil and gas pipelines for energy transportation is increasing. As the pioneering review in the field of ultrasonic defect detection for oil and gas pipelines based on bibliometric methods, this study employs visual analysis to identify the most influential countries, academic institutions, and journals in this domain. Through cluster analysis, it determines the primary trends, research hotspots, and future directions in this critical field. Starting from the current global industrial ultrasonic in-line inspection (ILI) detection level, this paper provides a flowchart for selecting detection methods and a table for defect comparison, detailing the comparative performance limits of different detection devices. It offers a comprehensive perspective on the latest ultrasonic pipeline detection technology from laboratory experiments to industrial practice.

Section: (B) Electromagnetic Ultrasonic-guided Waves Testingmentioning

confidence: 99%

Systematic Evaluation of Ultrasonic In-Line Inspection Techniques for Oil and Gas Pipeline Defects Based on Bibliometric Analysis

Huang,

Chen,

et al. 2024

“…Zhang et al developed an enhanced butterfly coil EMAT known as the Three-Square Permanent Magnets of Opposite Polarities (TSPM-OP). This innovation achieved a remarkable 4.97-fold enhancement compared to the conventional butterfly coil EMAT [24]. Jiang et al proposed a new non-uniform coil structure for a Raleigh wave EMAT (RW-EMAT), which enables signal compression in the spatial domain.…”

Section: Introductionmentioning

confidence: 99%

“…This innovation achieved a remarkable 4.97-fold enhancement compared to the conventional butterfly coil EMAT. [ 24 ]. Jiang et al proposed a new non-uniform coil structure for a Raleigh wave EMAT (RW-EMAT), which enables signal compression in the spatial domain.…”

Section: Introductionmentioning

confidence: 99%

Development of DMPS-EMAT for Long-Distance Monitoring of Broken Rail

Guo

Chui

et al. 2023

The safety of railway transportation is crucial to social and economic development. Therefore, real-time monitoring of the rail is particularly necessary. The current track circuit structure is complex and costly, posing challenges to monitoring broken tracks using alternative methods. As a non-contact detection technology with a lower environmental impact, electromagnetic ultrasonic transducers (EMATs) have become a concern. However, traditional EMATs have problems such as low conversion efficiency and complex modes, which can limit their effectiveness for long-distance monitoring. Therefore, this study introduces a novel dual-magnet phase-stacked EMAT (DMPS-EMAT) design comprising two magnets and a dual-layer winding coil arrangement. The magnets are positioned at a distance equal to the wavelength of the A0 wave from each other, while the center distance between the two sets of coils beneath the transducer is also equal to the wavelength. After analyzing the dispersion curves of the rail waist, it was determined that the optimal frequency for long-distance rail monitoring is 35 kHz. At this frequency, adjusting the relative positions of the two magnets and the coil directly underneath to be one A0 wavelength can effectively excite a constructive interference A0 wave in the rail waist. The simulation and experimental results show that DMPS-EMAT excited a single-mode A0 wave, resulting in a 1.35-times increase in amplitude.

“…The selection is made according to the quantity and level of various factors in the test, and representative points are selected from the comprehensive test to achieve results comparable with those of a large number of full-scale tests with the least number of tests [ 25 ]. Zhang [ 26 ] et al studied the influence of geometric parameters on the EMAT of a butterfly coil using orthogonal tests and designed an improved butterfly coil EMAT, whose signal was 4.97 times higher than that of the original butterfly coil EMAT. Jia et al [ 27 ] studied the degree of influence of the main parameters of the transducer on signal amplitude, and axial and radial focus migration using an orthogonal test method and selected the optimal parameter combination.…”

Section: Introductionmentioning

confidence: 99%

Antisymmetric Lamb Wave Simulation Study Based on Electromagnetic Acoustic Transducer with Periodic Permanent Magnets

Gao

Jia

2023

Self Cite

Due to its multi-mode and dispersion characteristics, Lamb waves cause interference to signal processing, which profoundly limits their application in nondestructive testing. To resolve this issue, firstly, based on the traditional EMAT, a horizontal polarization periodic permanent magnet electromagnetic acoustic transducer (HP-PPM-EMAT) was proposed. A 2-D finite element model was then developed to compare magnetic flux density, Lorentz force, and signal strength between the traditional EMAT and the HP-PPM-EMAT. The simulation results show that the HP-PPM-EMAT enhances the A0 mode Lamb wave (A0 wave) and suppresses the S0 mode Lamb wave (S0 wave). Finally, the influence of structural parameters of the HP-PPM-EMAT on the total displacement amplitude ratio of A0 and S0 was investigated using orthogonal test theory, and the width of magnet units was improved based on the orthogonal test. The results show that the total displacement amplitude ratio of A0 to S0 of the improved HP-PPM-EMAT can be improved by a factor of 7.74 compared with that of the traditional Lamb wave EMAT, which can produce higher-purity A0 mode Lamb waves.