29 |
P a g e
Figure 40 Report tab
Notes
•
A crack-like indication is typically set at a 90°phase in the Short and Long C-scans, and 45°
phase in the Raw C-scan. Signals with a phase angle greater than 90° are generally
characterized as transverse defects, while signals with a phase angle less than 90° are
characterized as geometrical effects from features on the part under test.
•
If a differential signal is appearing in the "Length" impedance plane but with a phase mostly
horizontal (giving generally no bright spot in the Depth C-Scans) this can typically be
considered as geometrical effect from the weld, such as excess of metal, undercut, etc.
•
Size defects shorter than 25 mm (1 in) with the Depth Short C-scan. Size defects longer than
25 mm (1 in) with the Depth Long C-scan.
Have a look at the transverse C-scan below (Tr layout). Generally, length signals have a color
opposite of axial cracks.
Figure 41 Transverse C-scan
