The method
A ring of ultrasonic transducers are attached round the pipe. The transducers send guided ultrasonic waves in both directions along the pipe. The waves are reflected by welds and corroded areas, or by other defects in the cross-section of the pipe.

Advanced software analyses the reflections in real time, generating a report of the condition of the pipe with locations of welds and corroded areas, if any. 

Applications
Long Range Ultrasonic Screening can be used to inspect: 

• Long pipelines where 100 % of the volume must be inspected
• Road and rail crossings, elevated pipework
• Insulated pipework and pipes through concrete walls 
• Sub-sea pipelines and offshore risers
• Pipe diameters from 3/4" up to 48" inclusive, and at temperatures between –40 °C og 125 °C

Range and sensitivity
Long Range Ultralyd Screening covers the following ranges:

• ± 150 m under ideal conditions
• ± 50 m for pipes with limited external or internal corrosion
• ± 25 m for somewhat corroded pipes
• ± 10 m for heavily corroded pipes
• ± 5 m for tar-coated pipes
• Up to 6 welds and up to 2 bends