Eddy Current Testing (ECT)

Eddy current testing is a noncontact method used to inspect non-ferromagnetic tubing. This technique is suitable for detecting and sizing metal discontinuities such as corrosion, erosion, wear, pitting, baffle cuts, wall loss, and cracks in nonferrous materials.

Two coils are excited with an electrical current, producing a magnetic field around them. The magnetic fields penetrate the tube material and generate opposing alternating currents in the material. These currents are called eddy currents.

Any defects that change the eddy current flow also change the impedance of the coils in the probe. These changes in the impedance of the coils are measured and used to detect defects in the tube.

Application:

• Condensers

• Feed water heaters

• Coolers

• Evaporators

• Chillers