Research at the University of Strathclyde in Scotland has led to an innovative system that uses sound waves to detect potentially dangerous cracks in pipes, aircraft engines, and nuclear power plants.

The University of Strathclyde department of mathematics and statistics research associate Katherine Tant was the chief academic researcher behind the study.

Transmission of varying sound waves can help to spot the structural defects easily.

Changing the duration and frequency of the sound waves can be used to recreate an image of the component’s interior, according to the report, which was published in the journal ‘Proceedings of the Royal Society A’.

Katherine Tant said: “Welds are vitally important in ‘safety critical’ structures, like nuclear power plants, aeroplane engines and pipelines, where flaws can put lives at risk. However, as with any type of bond, they constitute the weak part of the structure.

“One particular type of weld, made of austenitic steel, is notoriously difficult to inspect.

“We were able to devise solutions involving the use of ‘chirps’; coded signals with multiple frequencies which vary in time.

“The type of flaw identified depends on the method used. An analogy would be the type of echoes produced by clapping loudly in a cave; a single clap may allow you to judge the depth of the cave while a round of applause will give rise to a range of echoes, perhaps allowing you to locate boulders.”

The study was a part of the UK Research Centre in NDE Targeted Programme, and was funded by the Engineering and Physical Sciences Research Council, AMEC, the National Nuclear Laboratory, Rolls-Royce, Shell, and Weidlinger.