Magnetic Particle Testing (MT or MPI) is a non-destructive testing method for detecting surface and near-surface discontinuities in ferromagnetic pipeline materials — including cracks, laps, seams, porosity, and weld defects.

Magnetic Particle Testing (MT or MPI) is a non-destructive testing method for detecting surface and near-surface discontinuities in ferromagnetic pipeline materials — including cracks, laps, seams, porosity, and weld defects. MT is widely used during pipeline fabrication, construction, and maintenance inspection of exposed components.

The MT process involves magnetizing the inspection area and applying fine ferromagnetic particles (dry or in liquid suspension). Defects create localized magnetic flux leakage that attracts particles, forming visible indications under white or UV light. After inspection, the component is demagnetized.

MT is highly sensitive for surface defects on ferromagnetic materials but requires direct access to the pipe surface. For buried ferromagnetic pipelines, EMPIT’s CMI technology uses related magnetometric principles to detect corrosion, coating defects, and material anomalies from the surface — providing non-invasive inspection without excavation or pipeline shutdown.