Ultrasound testing uses high-frequency sound waves to penetrate materials. When a flaw such as a crack, void, or inclusion is present, the sound waves reflect differently or are attenuated in a characteristic manner. This allows inspectors to detect flaws that could compromise the structural integrity of rails or other components.
The Magnetic Particle Testing (MPT), also known as Magnetic Particle Inspection (MPI), is a non-destructive testing (NDT) method used to detect surface and near-surface flaws in ferromagnetic materials. This technique is particularly useful for inspecting components such as rails, welds, and other structures in the railway industry.
Eddy current testing, often used to inspect tubes, involves passing an alternating current through a coil to generate changing magnetic fields. These fields induce eddy currents in conductive materials like metal tubes. Here’s how it applies to tube inspection.
Eddy Currents Interaction: Eddy currents create their own magnetic fields, which interact with the primary magnetic field generated by the coil. Any discontinuities or changes in the material (such as cracks, corrosion, or changes in thickness) alter the eddy currents' flow and affect the impedance of the coil.