June 2, 2006
Petrochemical and power industries are expected to witness the greatest impact of the electromagnetic acoustic transducer (Emat) system, created to provide detailed surveys of pipe network integrity even in inaccessible areas.
The ultrasonic system uses “lamb waves” - a specific type of sound wave suited to discovering flaws in solid materials - to provide accurate pipe corrosion information.
The system can survey pipes horizontally and vertically and features a built-in device used to track its exact position, and employs probes which are mounted on a motor-driven scanner and directed at the surface of a target.
The device has the potential to scan up to 500m of pipe in a day, and is capable of detecting wall-losses of 10% or more in carbon steel, low-alloy pipework to high-alloy stainless steel structures.
MB Inspection technical development manager Alan Hipkiss says EMAT technology is ideally suited to ensuring pipe work meets increasingly stringent Health and Safety Executive guidelines.
“The HSE regulations have huge implications, so technology like this provides an additional resource to ensure compliance - particularly in the petrochemical and power industries,” said Mr Hipkiss.
“We designed the EMAT system with offshore applications in mind. It relays information directly to a computer for on-the-spot evaluation or off-line review.
“It can scan areas which would otherwise be inaccessible, including under pipe supports, and gives the potential to provide faster, more economical inspections.”
The EMAT technique is unaffected by coatings or light surface rust on pipes, and eliminates the need to remove insulation before surveys take place. The process is also accelerated as it is not dependent on the use of liquid couplant.