There are several types of non-destructive testing methods used to test welds for any discontinuities. One of these non-destructive testing methods is Eddy Current testing. Read below for all you need to know about Eddy Current weld inspections:
Eddy Current weld inspections are perfect for detecting surface cracks on conductive materials. These cracks can be detected even up to 0.5mm small and through coatings up to 2mm thick. Eddy Current weld inspections can be conducted on surfaces that are dry or wet, as well as surfaces that are extremely hot, due to the non-contact method of testing. These surfaces can also be tested with minimal preparation beforehand.
How it works
An AC current is applied to the probe found on Eddy Current weld testing equipment. The probe is then able to create an electromagnetic field that causes current flow within the surface as it glides above it. As the probe moves along the surface, the current flow will change to show flaws. The magnitude shown will depict the depth of the flaws.
Eddy Current testing is used for different applications. It is commonly used in many underwater applications as it is capable of detecting flaws in wet conditions. Therefore it is commonly used for weld testing on offshore rigs, as the rigs are in the ocean and are affected by constant moisture. They can also be used to detect flaws on ships and submarines. When it comes to weld testing on dry materials, Eddy Current testing is commonly used on amusement park rides, bridges cranes and more. It is used in these applications due to their consistency of loads that apply stress to the systems.