What is Magnaflux Leakage?
Magnaflux leakage or, to give it its correct name, Magnetic Flux Leakage (MFL) is a particular type of NDT that’s used to inspect steel structures. One common example of where it’s used is within the petrochemical industry, where the steel floors of storage tanks require regular testing.
How MFL works
MFL makes use of magnets to create a force in the area to be tested. Using our example of storage tanks, either permanent magnets or electromagnets will cause the floor to magnetise. This is then measured and any areas that are corroded will show ‘leaks’ in this magnetic field. Problems that can cause this to happen include:
- Wall loss
The readings returned also determine the depth within the floor that the problem is. In other words, is it on the surface or is it deeper within the material or on the base? The amount of flux leakage provides a good insight into the severity of the issue.
The advantages of MFL
One of the greatest benefits of using MFL for testing is its speed and relatively low costs. Others include:
- It can be used to test all ferromagnetic materials
- The equipment is highly portable
- It can be manually or automatically implemented (with selected, remotely operated systems)
- Small and light, MFL equipment can be attached to advanced robotics to carry out testing in difficult-to-reach areas or within toxic environments
- The returned data is simple to analyse
Again, using our example of petrochemical tank floors, it doesn’t take much imagination to understand the environmental harm from damage to the structure. Regular, proactive MFL testing will dramatically reduce the likelihood of accidental leaks caused by undiscovered tank floor weaknesses.
This core method of non-destructive testing is successfully utilised in many industries, including oil & gas, construction, infrastructure and more. MFL is one of the mainstays of NDT, with equipment examples, such as the Handscan and Pipescan being popular models. However, one area that’s changing the landscape of non-destructive testing is that of increasingly advanced levels of robotic systems.
One extraordinary example is Magneto, a cutting-edge robotic platform that uses advanced AI to navigate within even the most complex of geometrical structures. The ability to climb and carry out a huge variety of NDT simply by attaching the required sensors is, quite simply, the stuff of science fiction.