PAUT 6 dB Drop Sizing Test
Measure simulated half-amplitude limits, plot the indication relative to weld centreline, and submit your interpretation.
1. Inspection setup
Tip: Start at the indicated peak, then move the encoder left and right to measure half-amplitude points.
Set the cursor at each point where the envelope is approximately 6 dB below its peak (50.12% voltage ratio). Mark the two ends.
2. Trainee report
Weld centreline = 0. Negative toward 90° skew (left); positive toward 270° skew (right). Beam propagates left-to-right from 90° skew.3. Linked synthetic scan views
The orange encoder cursor and depth gate are linked to the training envelope. These views depict the selected scenario, not acquired inspection data.
V-prep weld cross-section
25 mm plate, 60° included angle, schematic cap and root. The highlighted region is the scenario reflector.
Reflector signature
Typical signatures are illustrative, not uniquely diagnostic. Orientation, probe side, frequency and geometry can change responses.
A-scan — amplitude vs sound path
Orange gate is centred on the simulated echo; the displayed path is based on the selected skip leg.
Linked cursor readings
Scan-position attenuation follows the same encoder envelope used in the sizing trace. Acoustic waveform is synthetic.
B-scan — encoder vs OD depth
S-scan — geometrically plotted sector
Tap the B-scan to move the encoder. S-scan plots synthetic ray responses in cross-sectional X/depth coordinates, including first/second-leg folding and a schematic V-prep overlay. No measured focal laws, probe calibration, or real material response are claimed.
4. Setup geometry and OD depth
Reference geometry uses a flat plate, 25 mm thickness and 60° refracted shear wave measured from OD surface normal. Ray tracing assumes a 90°-skew-side probe propagating toward 270° skew. In this exercise the data extractor keeps the leg explicitly: first or second.
For refracted ray path S from the idealized exit point, projected thickness coordinate = S × cos(60°). First-leg OD depth = projected coordinate. Second-leg OD depth = 2 × thickness − projected coordinate. The app must not mistake raw ray path for OD depth after a skip.
This training module uses a synthetic envelope and instructor-specified scenario truth. It does not infer vertical height from longitudinal 6 dB length sizing. Height is a separate field requiring a validated technique.