Magnetic Particle & Dye Penetrant Testing

For surface defects on magnetic materials, we utilize Magnetic Particle (MT) testing. Our portable MT yokes can be used on virtually any magnetic valve component to detect surface and slightly sub-service discontinuities.

MT testing is especially accurate at locating surface cracks that are hard to see with the naked eye. Additionally, MT can be used to confirm the presence of hot tears (interior cracks that open to the surface) originally revealed by radiography.

The Magnetic Particle Testing Process

Before magnetic particle testing starts, all external paint or coatings should be removed in order to ensure testing accuracy. The surface is then covered in a magnetic testing material such as powder or ink.

Next, the MPI equipment applies a magnetic field in one direction across the surface. If the magnetic powder or ink behaves unexpectedly during the test, it indicates a surface or subsurface discontinuity. To ensure accurate testing, the procedure must be repeated in a second direction perpendicular to the first.

After testing, the valve component must be thoroughly cleaned and demagnetized.

Reliable Test Results for Your Industrial Valves

United Valve has earned its reputation for reliability by consistently detecting even the smallest, seemingly invisible imperfections in industrial valves. Rely on us for dependable industrial valve testing results every time.