Ultrasonic TOFD
The TOFD (Time of Flight Diffraction) ultrasonic process is partially or fully mechanized. A computer is required to record and display the determined data. The TOFD technology is primarily used for weld seam testing in pipeline construction and provides reliable results on defect sizes.
Weld seams mechanically tested
Qualitech uses TOFD ultrasonic technology primarily for testing welding seams on pipelines in hydropower plants. In TOFD ultrasonic testing, two separate angle probes – a transmitter and a receiver – are assigned to each other, with one transmitting ultrasonic signals and the other receiving the signals. The probes – integrated in a partially or fully mechanized robot – are guided along welding seams. At the same time, an incremental encoder provides information about the distance travelled. Unlike conventional ultrasonic testing, this technology does not acquire reflection signals, but diffraction signals, which allows relatively precise statements to be made about errors in terms of length, depth and height.