In order to design a Magnetic Flux Leakage (MFL) tool, knowledge of the magnetic field profile both within the pipe wall and around the sensor locations is required. The former is important since the magnitude of a defect signature will be maximised when the pipe wall is magnetically saturated. The latter is important for the reason that the background magnetic field profile will determine the sensor bias level for a given defect. Previous research using the Finite Element (FE) technique has investigated the magnetic field profile within the pipe wall for a generic circumferential MFL tool and showed how it varied depending upon the pipe wall thickness and tool speed. It was found that as the pipe wall thickness and tool speed increased, a plume of magnetic flux formed behind the tool. Furthermore, it was observed that as the pipe wall thickness increased, outer regions of the pipe wall exhibited substantially reduced levels of magnetic flux. A reduction of magnetic flux in these outer regions of the pipe wall suggests defects located here may be harder to detect and resolve compared to defects located closer to the inner pipe wall. This paper briefly reviews the previous research and extends the numerical analysis by considering the magnitude of the magnetic field profile for locations within the inner and outer pipe wall and possible sensor positions. It is shown how these profiles change with pipe wall thickness and tool speed and demonstrates the complex and non-linear nature of the magnetic field. The information obtained can be combined with previous research and will be useful for determining the optimal sensor location and yield predictions for background magnetic field magnitudes. The full complexity of magnetic materials is not incorporated into the modelling, however, the results obtained give a theoretical indication of operational limitations of the circumferential MFL technique.
Skip Nav Destination
2006 International Pipeline Conference
September 25–29, 2006
Calgary, Alberta, Canada
Conference Sponsors:
- Pipeline Division
ISBN:
0-7918-4262-2
PROCEEDINGS PAPER
Challenges in Circumferential Magnetisation II: A FEA Point of View Available to Purchase
R. C. Ireland,
R. C. Ireland
QinetiQ, Farnborough, Hampshire, UK
Search for other works by this author on:
C. R. Torres
C. R. Torres
Tuboscope Pipeline Services, Houston, TX
Search for other works by this author on:
R. C. Ireland
QinetiQ, Farnborough, Hampshire, UK
C. R. Torres
Tuboscope Pipeline Services, Houston, TX
Paper No:
IPC2006-10093, pp. 107-116; 10 pages
Published Online:
October 2, 2008
Citation
Ireland, RC, & Torres, CR. "Challenges in Circumferential Magnetisation II: A FEA Point of View." Proceedings of the 2006 International Pipeline Conference. Volume 2: Integrity Management; Poster Session; Student Paper Competition. Calgary, Alberta, Canada. September 25–29, 2006. pp. 107-116. ASME. https://doi.org/10.1115/IPC2006-10093
Download citation file:
10
Views
Related Proceedings Papers
Related Articles
The Design of a Mechanical Damage Inspection Tool Using Dual Field Magnetic Flux Leakage Technology
J. Pressure Vessel Technol (August,2005)
Non-Contact Measurement of Residual Magnetization Caused by Plastic Deformation of Steel
ASME J Nondestructive Evaluation (August,2020)
Profiles of Two JOMAE Associate Editors (A Continuing Series)
J. Offshore Mech. Arct. Eng (October,2021)
Related Chapters
Openings
Guidebook for the Design of ASME Section VIII Pressure Vessels, Third Edition
Openings
Guidebook for the Design of ASME Section VIII Pressure Vessels
Predicting and Evaluating Ferrite Content in Austenitic Stainless Steel Castings
Stainless Steel Castings