Magnetic Flux Leakage (MFL)
Magnetic Flux Leakage (MFL) is a rapid electromagnetic non-destructive screening technique deployed extensively for high-throughput evaluation of ferromagnetic assets, notably carbon steel tubes in air-cooled heat exchangers (fin-fan coolers), process pipework, and above-ground storage tank bottoms.
During tube examination, an internal probe outfitted with powerful rare-earth permanent magnets drives the carbon steel tube wall into near-magnetic saturation. Wherever wall loss, pitting, or cracking is present, the magnetic flux lines can no longer be fully accommodated within the reduced steel cross-section and \"leak\" into the adjacent air space. Highly sensitive Hall-effect sensors and search coils capture this flux leakage, instantaneously pinpointing flaw location and relative severity.
MFL is particularly advantageous for fin-fan cooler tubes wrapped with external aluminium fins, where complex exterior geometry obstructs other testing techniques. Furthermore, motorised MFL floor scanners enable rapid, comprehensive screening of large petrochemical storage tank floors, detecting soil-side underside corrosion and top-surface pitting before breach or product leakage occurs.
Key Technical Highlights & Capabilities
Finned Tube High-Volume Screening
Rapid, dependable screening of carbon steel air-fin cooler tubes fitted with external aluminium or copper fins.
Expedited Inspection Productivity
High pull speeds facilitate hundreds of tubes or expansive tank floor sectors to be surveyed per single work shift.
Tank Floor & Shell Integrity
Detects underside soil-side corrosion and product-side pitting across atmospheric storage tank bottoms.
Surface Scale Tolerance
Inspects effectively through light oxide and rust scale without requiring aggressive chemical cleaning.
Require Magnetic Flux Leakage (MFL) for Your Facility?
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