Magnetic flux leakage is a rapid and robust corrosion detection technique. It relies upon strategically placed Hall Effect sensors to detect the magnetic leaking field that is created by corrosion. On its own, MFL cannot differentiate if the corrosion is topside or bottom side of the tank bottom.
STARS (Surface Topology Air-gap Reluctance Sensors) are a patented technology that determines whether corrosion is top side or bottom side.
STARS also provide a simple visual representation of the inspection surface through thick non-magnetic material up to 10 mm thick.
The Floormap3D has a total of 256 sensors, enhancing lateral resolution to detect smaller defects, and reduce sensitivity to defect orientation. The top surface discrimination works effectively through up to 6 mm (1/4″) coating, enabling effective tank inspection without coating removal.

A MFL map of a tank floor showing corrosion

Benefits of MFL :

• The high-resolution sensors of Floormap yield an excellent Probability of Detection (PoD) of a defect as small as 2 mm (0.08 in) in diameter. When used with advanced signal processing and defect classification tools, corrosion detection and sizing capability are significantly improved over other systems.
• Floormaps are some of the fastest motor-driven scanners improving inspection efficiency and reducing the time spent in tanks.
• Floormap collects crucial inspection data very quickly, which is made possible by the high-power, rugged touch-screen computer, and advanced software processing built-in then produces detailed plan views of inspection areas and offer a more in-depth understanding of the tank bottoms without the need for complex signal interpretation, as seen with other NDT technologies.These powerful tools can speed up the inspection process, reduce the amount of UT prove up, while increasing inspection confidence, which leads to better Risk-Based Inspection (RBI) calculations. Having this information in an easy-to-understand format leads to faster and more reliable inspections and maintenance decisions.