Magnetic Flux Leakage

Magnetic flux leakage (MFL) is a nondestructive testing technique that is uses electromagnetism to search for flaws or damage in ferromagnetic materials. Sentinel Integrity Solutions uses MFL to inspect the floors of tanks for flaws and damage.

MFL works by using either permanent magnets or electromagnets to create a magnetic field in the tank floor. Where the tank is in proper condition, the magnetic field should be uniform. Any defects in the tank floor will cause the magnetic field to “leak” or distort. By examining the field around the part of these distortions, it is possible to find damage or flaws within the tank floor.

Mark III Tank Floor Scanner

To perform magnetic flux leakage testing, Sentinel Integrity Solutions uses a device known as the MFE Mark III Tank Floor Scanner. The Mark III Tank Floor Scanner is a manually operated device that is able to perform MFL tests and display the results in real time on its touch screen display.

The Mark III Tank Floor Scanner has a motor so that it is able to drive itself. It also has the ability to stop and alert the inspector whenever it finds a defect.

Applications of Magnetic Flux Leakage

Magnetic flux leakage is able to inspect for several types of damage in tank floors, such as wall loss, corrosion, and pitting. Because it uses magnetism, MFL is also useful in that it can be used to inspect lined or coated tank floors and piping.

Benefits of Using the Mark III Tank Floor Scanner for Magnetic Flux Leakage

The MFE Mark III Tank Floor Scanner has numerous advantages over earlier models. For example, it is more accurate when inspecting coated tank floors, or those with thicker plates, due to its improved Magnetic Bridge.

The Mark III Tank Floor Scanner is able to display scan results in real time. It also allows the operator to easily adjust the gain and set the alarm. It is this alarm that allows it to be set to stop when a defect has been detected. A signal limit is set, so if the sensor detects a signal that passes that limit, the motor will stop and alert the inspector. Also, the system’s display screen will stop on the signal as well so the inspector can identify the signal more easily.


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