Olympus nortec 600 - Figure 5-231 the SWP + IMP Display after Inspecting the Entire Tube; Figure 5-232 an NFT Probe with an Absolute Exciter-Pickup Configuration; NFT Erosion and Corrosion (Absolute) - NORTEC 600 D Model

DMTA-10040-01EN, Rev. E, February 2018
Chapter 5286
Figure 5‑231 The SWP + IMP display after inspecting the entire tube
5.4.6 NFT Erosion and Corrosion (Absolute) — NORTEC 600D Model
In this near-field testing (NFT) application, an absolute configuration is used to
identify volumetric or gradual internal defects such as erosion and corrosion in finned
air-cooler tubing. An example NFT probe is shown in Figure 5-232 on page 286.
Figure 5‑232 An NFT probe with an absolute exciter‑pickup configuration
The absolute configuration helps quantify the amount (depth) of internal wall loss in
tubing (see Figure 5-233 on page 287). The NORTEC 600 simply measures the
corresponding amplitude of the absolute liftoff signal using the divisions of the
impedance plane grid.