Magnetic flux leakage (MFL) testing is a non-destructive electromagnetic technique that uses magnetic sensors to detect defects in conductive materials, such as steel:
How it works
A powerful magnet magnetizes the material, and a magnetic detector between the magnet’s poles detects the magnetic field that leaks from defects.
What it can detect
MFL can detect a variety of defects, including corrosion, pitting, cracks, and cavities, both on the surface and subsurface.
Where it’s used
MFL is commonly used to inspect pipelines and storage tanks, especially in the petrochemical industry.
How to perform MFL testing
The key steps are:
- Plan the pre-inspection
- Use calibrated MFL probes
- Slowly pull the probe to capture data
- Have a qualified analyst evaluate the data
