Comparison of NDT Methods for Tubing

Any tubing inspection should be used in conjunction with a Hydrostatic, pneumatic, or Helium leak test prior to placing a component back into service.

Eddy Current (ECT) Remote Field (RFT) XRFT IRIS Flux Leakage
Material Non-Ferrous Ferrous Ferrous Both Ferrous
Pull Speed Fast (12X) Medium (1.5X → 12X) Slower (2X → 6X) Slow (1.5X) (12X max)
Tube Cleanliness Clean Clean Clean Very Clean Clean
U-Bend Capable Yes, Flexible Yes, Flexible Outer Radius
Wall Thickness Range .022" → .135" .028" → .300" .049" → .120" >.065" .028" → .109"
Accuracy ±10% ±10% ±10% ±.003" Limited
Flaws Under Tubesheet Limited ID Only
Flaws At or Adjacent to Baffle Good Limited ID Only Excellent Good
Discern ID vs. OD Flaws
Discern Through-Wall Hole Limited
Axial Cracking >50% Limited
Circumferential Cracking Array Only >25% Limited