Time of Flight Diffraction (TOFD)

Time of Flight Diffraction (TOFD)：

a. Purpose:
    Accurate sizing of crack depth, height, and length features.

b. Principle:
                   

c. Feature:
1). High sizing accuracy (±1mm)
2). High scanning speed (2-4m/min)
3). The sizing of defect size can be checked.
4). The orientation of the discontinuities has insignificant effect on the detection.
5). The size of the defect does not based on the amplitude  of the signals.
6). In addition to A-, B-, D-Scan image display, various post-processing can be used to enhance analysis on detection data. 

d. Application: 
Used to detect discontinuities in weld bead for pressure vessels, storage tanks and pipelines, and crack tracking detection.