Time of Flight Diffraction in lieu of Radiography


The Southern Ireland based client had a requirement to replace radiographic testing with an automatic encoded ultrasonic system in accordance with BS EN ISO 10863 due to the excess site restrictions by their NDT contractor performing onsite industrial radiography.


Time of flight diffraction (TOFD) was selected as the automated ultrasonic testing technique for its ability as a screening tool that can rapidly scan welds and produce very accurate measurements of any defects found. The client had numerous weld bevels types & dimensions which were difficult to detect planar defects when using radiography, therefore TOFD was selected for its ability to accurately measures defects, regardless of the defects' orientation

A full validation was performed in accordance with BS EN ISO 10863, where numerous welded samples containing seeded defects were successfully scanned & analysed.

Forth Inspection Service developed the TOFD procedure, oversaw the validation process & provides ongoing support, including offline analysis of data via a dedicated Dropbox.