Non-destructive inspection of ferromagnetic pipes based on the discrete Fourier coefficients of magnetic flux leakage

2014 ◽  
Vol 115 (17) ◽  
pp. 17E509 ◽  
Author(s):  
T. Nara ◽  
M. Fujieda ◽  
Y. Gotoh
Keyword(s):  
Magnetic Flux ◽  
Fourier Coefficients ◽  
Magnetic Flux Leakage ◽  
Non Destructive ◽  
Flux Leakage

Characterization of Mechanical Damage Through Use of the Tri-Axial Magnetic Flux Leakage Technology

2006 ◽  
Author(s):  
Vanessa Co ◽  
Scott Ironside ◽  
Chuck Ellis ◽  
Garrett Wilkie
Keyword(s):  
Magnetic Flux ◽  
Mechanical Damage ◽  
Magnetic Flux Leakage ◽  
Metal Loss ◽  
Field Investigations ◽  
Non Destructive ◽  
Flux Leakage

Management of mechanical damage is an issue that many pipeline operators are facing. This paper presents a method to characterize dents based on the analysis of the BJ Vectra Magnetic Flux Leakage (MFL) tool signals. This is an approach that predicts the severity of mechanical damage by identifying the presence of some key elements such as gouging, cracking, and metal loss within dents as well as multiple dents and wrinkles. Enbridge Pipelines Inc. worked with BJ Services to enhance the knowledge that can be gained from MFL tool signals by defining tool signal subtleties in dents. This additional characterization provides information about the existence of gouging, metal loss, and cracking. This has been accomplished through detailed studies of the ILI data and follow-up field investigations, which validate the predictions. One of the key learnings has been that the radial and circumferential components of the MFL Vectra tool are highly important in the characterization and classification of mechanical damage. Non-destructive examination has verified that predictions in detecting the presence of gouging and cracking (and other defects within dents based on tool signals) have been accurate.

scholarly journals Magnetic Flux Leakage Course of Inner Defects and Its Detectable Depth

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Jianbo Wu ◽  
Wenqiang Wu ◽  
Erlong Li ◽  
Yihua Kang
Keyword(s):  
Magnetic Flux ◽  
Steel Structure ◽  
High Sensitivity ◽  
Magnetic Flux Leakage ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Near Surface ◽  
Testing Method ◽  
Non Destructive ◽  
Flux Leakage

AbstractAs a promising non-destructive testing (NDT) method, magnetic flux leakage (MFL) testing has been widely used for steel structure inspection. However, MFL testing still faces a great challenge to detect inner defects. Existing MFL course researches mainly focus on surface-breaking defects while that of inner defects is overlooked. In the paper, MFL course of inner defects is investigated by building magnetic circuit models, performing numerical simulations, and conducting MFL experiments. It is found that the near-surface wall has an enhancing effect on the MFL course due to higher permeability of steel than that of air. Further, a high-sensitivity MFL testing method consisting of Helmholtz coil magnetization and induction coil with a high permeability core is proposed to increase the detectable depth of inner defects. Experimental results show that inner defects with buried depth up to 80.0 mm can be detected, suggesting that the proposed MFL method has the potential to detect deeply-buried defects and has a promising future in the field of NDT.

scholarly journals Study on design and fabrication of a prototype equipment used for corrosion inspection on petrochemical tank bottom by magnetic flux leakage method

2020 ◽  
pp. 280-288
Keyword(s):  
Magnetic Flux ◽  
Permanent Magnets ◽  
Low Cost ◽  
Scanning Speed ◽  
Magnetic Flux Leakage ◽  
Corrosion Pitting ◽  
Tank Bottom ◽  
Hall Sensors ◽  
Non Destructive ◽  
Flux Leakage

Corrosion of the bottom of the petroleum tank may lead to a product leak that could cause a fire or explosion resulting in damage to people and the environment, therefore the test of tank bottom corrosion is necessary to be conducted periodically to prevent the occurrence of the above problems. In non-destructive inspection, the Magnetic Flux Leakage (MFL) method relies on the variation of fluxes caused by defects on the surface of materials to detect corrosion, pitting, or imperfections, which is proved quite effectively with low cost. The project was implemented to develop a prototype of the MFL bottom detection device based on the research results in the world to improve corrosion survey capacity in industrial equipment, as well as to improve the expertise in the Research Team of electronics and automation in the fields of magnetic fields and sensors. As a result, an MFL model using permanent magnets and Hall sensors were fabricated. Survey experiments showed that the machine could detect corrosion defects up to 20% of steel wall thickness in the scanning speed range from 500 mm/s to 1130 mm/s. However, to meet the actual survey needs, the team must continue to improve the device in terms of sensitivity, scanning speed, the ability to operate automatically or semi-automatically, and register for a fire safety inspection.

Magnetic Flux Leakage Method of Railway Rails Defects diagnostics and its Place Among Mobile Means of Non-destructive Testing

2018 ◽  
pp. 105-119
Author(s):  
Nichoha, Vitalij ◽  
Shkliarskyi, Volodymyr ◽  
Storozh, Volodymyr ◽  
Matiieshyn, Yurij ◽  
Vashchyshyn, Liubomyr
Keyword(s):  
Magnetic Flux ◽  
Magnetic Flux Leakage ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Non Destructive ◽  
Flux Leakage

scholarly journals Inspection of Gas Pipelines Using Magnetic Flux Leakage Technology

2017 ◽  
Vol 17 (3) ◽  
pp. 37-45 ◽  
Author(s):  
Z. Usarek ◽  
K. Warnke
Keyword(s):  
Signal Processing ◽  
Magnetic Flux ◽  
Development Stage ◽  
Magnetic Flux Leakage ◽  
Destructive Testing ◽  
Oil Pipelines ◽  
Recorded Data ◽  
Pipeline Wall ◽  
Non Destructive ◽  
Flux Leakage

Abstract Magnetic non-destructive testing methods can be classified into the earliest methods developed for assessment of steel constructions. One of them is the magnetic flux leakage technology. A measurement of the magnetic flux leakage is quite commonly used for examination of large objects such as tanks and pipelines. Construction of a magnetic flux leakage tool is relatively simple, but a quantitative analysis of recorded data is a difficult task. Therefore, methods of magnetic flux leakage signal processing and analysis are still under development. A magnetic flux leakage in-line-inspection tool called FLUMAG 500 was constructed. FLUMAG 500 was designed for gas and oil pipelines inspection. In this paper principle of operation of FLUMAG 500 was described. Advanced algorithms of the signal processing and analysis was also developed. Results coming from the development stage as well as from the final construction of the tool were presented. Analysis of these results shows that FLUMAG 500 is a suitable tool for detection of corrosion defects in a pipeline wall.

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