Near Field Testing (NFT): Precision Inspection for Ferromagnetic Tubes
Near Field Testing (NFT) is an electromagnetic tube inspection technique designed for ferromagnetic tubes where internal pitting and erosion are expected. It is especially effective in areas where baffle plates are present, providing accurate detection of localized corrosion.
How It Works
Near-Field Coil Placement
The probe positions sensing coils close to the transmitting coil to operate within the near field of the magnetic flux.
Flaw Interaction
Internal defects, pitting, and localized corrosion disturb the magnetic field.
Signal Detection
Disturbances are measured by the coils, allowing the inspection system to identify and locate defects.
Key Advantages of NFT
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High Sensitivity: Detects internal pitting and erosion effectively.
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Unaffected by Baffles: Works accurately even in complex tube geometries.
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Fast and Reliable: Provides quick inspection results for preventive maintenance.
Ideal Applications
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Ferromagnetic heat exchanger tubes
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Boiler tubes with expected internal corrosion
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Fin-fan and condenser tubes
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Industrial systems requiring precise defect detection