The Near Field Testing (NFT) is intended specifically for fin fan carbon steel tubing inspection. This is among the latest technique which is widely used to replace Magnetic Flux Leakage (MFL) for tubes where NFT is proven faster and provide more reliable results. NFT technology uses two coils — a transmitter and a receiver. Typically the receiver coil is close to the transmitter coil, taking advantage of the transmitter’s near-field zone, which is the zone where the magnetic field from the transmitter coil induces strong eddy currents, axially and radially, in the tube wall. NFT probes operate within the same frequency range as Remote Field Testing (RFT) probes.
This technique is recommended as primary inspection of Fin Fan with IRIS Back-up and specifically suited to the detection of internal corrosion, erosion, or pitting on the inside of carbon steel tubing.
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