types of testing we offer
Contact DBI for a Magnetic Particle Inspection
- Pre-clean the area to be inspected.
- The part must be dry and free of rust, dirt, scale, and oil.
- Introduce the magnetic field.
- Use permanent magnets, an electromagnetic yoke, prods, a coil, or other means to establish the necessary magnetic flux.
- Apply magnetic particles.
- Magnetic particles can be suspended in an oil/water solution or can be dry. They can also be in a visible dye form or fluorescent with the use of a black light.
- Visually inspect the area.
- A skilled inspector must interpret indications that are formed after applying the magnetic field. This requires the person to distinguish between relevant and irrelevant indications.
Advantages of Magnetic Particle Inspection
- Can detect both surface and near subsurface indications.
- Can easily inspect parts with irregular shapes.
- Pre-cleaning is not as critical as for some other material inspection methods.
- Fast method of inspection and indications are visible directly on the specimen surface.
- Considered low cost compared to many other NDT techniques.
- Very portable inspection, especially when used with battery-powered equipment.
Disadvantages of Magnetic Particle Inspection
- Only effective for the examination of ferromagnetic materials.
- Discontinuity detection is limited to those at or near the surface.
- Demagnetization may be required before, between, and after inspections.
- Discontinuities will only be detected when the major axis interrupts the primary flux lines. This necessitates inspection in more than one direction to assure discontinuity detection regardless of orientation.
- Paint and/or coating removal is necessary.