Eddy Current Testing (ECT)

ECT, when referring to the non-destructive testing of tubular products, stands for Eddy Current Testing. This is a highly sensitive electromagnetic inspection technique used to detect surface and near-surface flaws in conductive materials, such as metal tubes and pipes.

Principle and Application

ECT works by passing an alternating current through a coil placed near the material. This current induces circulating electrical currents, known as eddy currents, within the metal itself.

When the eddy currents encounter a discontinuity, like a crack, pit, or inclusion, their flow is disrupted. This disruption changes the impedance of the test coil, which is then measured by the instrument. Since the signal is instantly affected by these flaws, ECT is exceptionally fast and is often integrated directly into the production line of a tube mill. It is a critical method for quickly verifying the quality of welds and ensuring the integrity of the material before further processing.