Magnetic Particle Inspection Level 2 Practice Exam

What can provide a challenge when examining defects more than 2 inches below the surface?

1. High magnification required

2. Depth of inspection

3. Surface signal interference

4. Proficient operator skills

The correct answer is: Depth of inspection

When inspecting for defects that are located more than 2 inches below the surface, the depth of inspection becomes a significant challenge. This is primarily because magnetic particle inspection (MPI) is inherently limited in its ability to detect defects that are farther away from the surface due to the attenuation of the magnetic field and the magnetic particles themselves. As the distance from the surface increases, the magnetic field strength diminishes as does the effectiveness of the magnetic particles to reveal discontinuities. Therefore, defects at greater depths may not produce sufficient indications on the surface, making detection difficult. This limitation underscores the importance of understanding the material thickness and the techniques used for MPI to ensure that appropriate methods are applied for deeper inspections. Correctly identifying and adapting to these depth challenges is crucial for achieving the intended inspection outcomes, which is why depth of inspection is highlighted as a primary obstacle in this scenario.