Magnetic Particle Tests ( NDT ) AND ITS PROCESS

Magnetic Crack Detection apparatus is designed to detect normally invisible cracks on or extending near to the surfaces of articles made of magnetic materials.

The design of magnetic crack - detectors is based on the principle that, if a crack or flaw is present in a magnetic material through which a magnetic field is passing, the lines of force will be distorted near the fault owing to the local change of permeability associated with it. In the case of a piece without any flaw, lines of force will be uniform an straight.

Cracks and flaws can also be detected by magnetizing a ferrous metallic part , then sprinkling very fine iron dust over it. The magnetic poles formed at the crack gather a line of dust and outline the crack. The special equipment for this magnetic testing for cracks is known as magnaflux.

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Mechinopedia For Mechanical Engineers

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