Advanced & Mechanised NDT - E Mat (Under Support Corrosion)

Electromagnetic acoustic transducer (EMAT) evaluation relies on the use of ultrasonic energy to induce an alternating current within a magnetic field. EMAT testers typically employ two probes. The pulser probe sends an ultrasonic signal in both directions around the circumference of a pipe under examination, and the receiver probe receives signals from both directions. Changes in the sound path and time of flight of the ultrasonic signal indicate changes in the material, such as wall loss. EMAT evaluation can be used on any piping that is physically accessible, including elevated piping, dock lines and sleeper racks. EMAT evaluation can also be used with both above and below ground storage tanks, fiberglass structures and rotating machinery.

The advantages of EMAT evaluation include:

• Allows for the rapid scanning of long piping runs to identify locations of possible defects for further inspection and evaluation
• Can detect isolated defects as small as 1/8” in diameter, as well as generalized wall loss from corrosion and/or erosion
• The technology does not require total access to access the data needed for inspection. Instead, access to only one third of the line circumference is required to send full volumetric sound through the pipe
• Provides accurate information for support touch point inspections