EMAT (Electromagnetic Acoustic Transducer) is an ultrasonic inspection technology that generates sound waves directly in the pipe wall using electromagnetic forces — without requiring liquid couplant between transducer and surface.

EMAT (Electromagnetic Acoustic Transducer) is an ultrasonic inspection technology that generates sound waves directly in the pipe wall using electromagnetic forces — without requiring liquid couplant between transducer and surface. This dry-coupling capability makes EMAT particularly valuable for gas pipeline inspection where conventional UT pigs cannot operate.

EMAT technology uses the interaction between a magnetic field and eddy currents to generate ultrasonic waves (typically shear horizontal waves) within the pipe material. This enables:
• Crack detection — especially stress corrosion cracking (SCC) in gas pipelines.
• Coating-independent inspection — no need to remove coatings for external EMAT testing.
• Gas pipeline ILI — EMAT pigs inspect gas lines where UT pigs require liquid coupling.

EMAT limitations include lower sensitivity compared to conventional UT for wall thickness measurement and higher equipment complexity. EMAT pigs also require piggable pipeline geometry.

For unpiggable pipelines where EMAT pigs cannot be deployed, EMPIT’s CMI technology provides aboveground corrosion detection and integrity assessment from the surface — complementing EMAT capabilities for comprehensive pipeline integrity programs.