Eddy Current Inspection (EC)
Eddy Current Inspection (EC) is a technique used to detect surface breaking discontinuities in all electrically conducting materials. Uses include material sorting and in-service tube, bar and weld inspection. The main advantage is that testing can be conducted without the need to remove paint or surface coatings. Typical site applications include inspection of crane jibs, pedestals, pad-eyes (pre and post loading), drilling derrick substructures and wind turbine towers.
An alternating current is applied to an inspection coil, which creates a magnetic field. When placed next to a suitable test material, it induces an ‘eddy current’ into the test material. The presence of defects and material variations in the test material, affects the characteristics of the induced eddy currents. These changes are detected by an excitation coil and are displayed on a digital screen.