What are the main advantages and limitations of RFT for pipeline inspection compared to other NDT methods?

2 Advantages of RFT

RFT is a beneficial NDT method for pipeline inspection, as it can inspect long distances of pipe with a single probe and detect defects in both the inner and outer surfaces of the pipe. Additionally, it can inspect pipes with coatings, linings, or insulation as long as they are non-conductive and thin enough to allow the magnetic field to penetrate. RFT is also advantageous when inspecting pipes with complex geometries, such as bends, elbows, tees, and reducers, without compromising accuracy. Furthermore, it can inspect pipes with varying diameters, wall thicknesses, and materials as long as they are ferromagnetic and have a sufficient wall-to-bore ratio.

3 Limitations of RFT

RFT has some limitations that must be taken into account before selecting it as the best NDT method for pipeline inspection. It cannot inspect non-ferromagnetic pipes and cannot detect defects parallel to the pipe axis, nor can it distinguish between different types of defects. Additionally, external sources of noise or interference may reduce the signal quality or cause false indications, and calibration and interpretation by qualified personnel may be required due to the complexity and sensitivity of the signals.

4 Tips for choosing the best NDT method

RFT is not the only NDT method available for pipeline inspection. Depending on the specific requirements and conditions of your pipeline project, you may need to consider other methods such as ultrasonic testing (UT), eddy current testing (ECT), and magnetic flux leakage (MFL). UT can detect and measure defects in non-ferromagnetic pipes, however it may be affected by coating thickness, surface roughness, or curvature of the pipe. ECT can inspect non-ferromagnetic pipes and provide high-resolution images of the pipe condition, but it cannot inspect pipes with coatings, linings, or insulation. MFL can inspect ferromagnetic pipes and detect defects in both the inner and outer surfaces of the pipe, but it cannot inspect pipes with complex geometries. The best NDT method for pipeline inspection depends on several factors, so it is important to consult with an NDT expert before deciding which method to use.

5 Here’s what else to consider

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