[jaden]

MFL and LFET are methods used for scanning tank floors, piping, and tubing inspection. What application are you are interested in?
I’ll focus on tank floor / tank bottom inspection as that’s a common reason these technologies are compared.

There isn’t a lot of detail published online about LFET capabilities, but the benefits against MFL are usually sold as being lightweight, ability to differentiate against soil side and product side corrosion, capabilities on both ferrous and non-ferrous materials, and ability to work through layers of scale or dirt.

By comparison MFL can be considerably faster, works on ferrous materials only, is applied more widely so there is a larger body of knowledge available, is arguably less operator dependent and easier to use.

Capabilities and features will vary depending on the MFL scanner used. There are rudimentary ‘detection only’ options, and more advanced high resolution mapping systems, complemented with feature rich analysis and reporting software tools for both the operator and tank owner/operator.
Most MFL scanners perform well on the common plate and coating thicknesses found on storage tanks.

MFL alone cannot differentiate between top side and bottom side corrosion, but more advanced MFL scanners use additional technologies to perform this:- Some use Eddy-Current sensors, Silverwing developed STARS technology, which also gives an excellent visual of the upper surface of the plate – https://www.eddyfi.com/en/product/floormap-mfl-tank-bottom-inspection

To help your research, below are links to various articles and papers relating to MFL:

Discrimination of top and bottom discontinuities with MFL and STARS – https://eddyfi.com/doc/Downloadables/Floormap3D_STARS-01.pdf

Improving Confidence in Tank Inspection – https://eddyfi.com/doc/Downloadables/tank-inspection-confidence-01.pdf

Factors that affect the defect sizing capabilities of the Magnetic Flux Leakage Technique – https://eddyfi.com/doc/Downloadables/sizing-capabilities-of-magnetic-flux-leakage-01.pdf

Practical capabilities of MFL in steel plate inspection – https://eddyfi.com/doc/Downloadables/Practical_limits_of_MFL_in_steel_plate_inspection-01.pdf

Capability of modern tank floor scanning with Magnetic Flux Leakage -https://eddyfi.com/doc/Downloadables/capability-of-modern-tank-floor-scanning-with-Magnetic-Flux-Leakage-01.pdf

Efficient inspection from measurement collection through to report – https://eddyfi.com/doc/Downloadables/Efficient-inspection-from-measurement-collection-through-to-report-01.pdf

Due to the Covid-19 situation many of our experts are working from home and will be glad to discuss MFL in more detail. Perhaps I can arrange an hour online meeting so we can hold an in-depth discussion about the Eddyfi range of MFL Tank Floor or piping scanners?