Volumetric

Module from the Inspection and NDE Curriculum curriculum.

Module 3 - Volumetric NDE (RT, UT) · Learning Objectives · 1. Select X-ray or gamma-ray (Ir-192, Co-60) for RT · 2. Apply ASME V Article 2 radiography technique + sensitivity · 3. Perform UT thickness per ASME V Article 4 · 4. Select straight-beam vs angle-beam for weld inspection · 5. Distinguish echo from backwall, flaw, and mode conversion · Radiography Sources

Source	Energy (keV)	Thickness Range	Cost	Safety	Typical Use
X-ray tube 160 kV	160 max	< 1 in steel	Moderate	Shielded room	Shop RT
X-ray tube 300 kV	300 max	< 2 in steel	Higher	Shielded	Larger shop
Ir-192	300-600 (avg 370)	< 2.5 in steel	Low	Licensing	Field RT most common
Co-60	1.17 + 1.33 MeV	2 - 7 in steel	Low	Heavy shielding	Thick sections
Se-75	66-401 keV	< 1 in steel	Moderate	Lighter shielding	Thin, high contrast
Yb-169	63-308 keV	< 0.5 in	Moderate	Lightest	Very thin
UT Techniques
Technique	Use	Probe	Coupling	Flaws Detected	Notes
Straight-beam UT	Thickness, backwall flaws	0 degree	Fluid/gel	Laminations, wall loss	Most common
Angle-beam UT	Weld inspection	45-70 deg	Gel	Crack, LOF, LOP	Standard weld NDE
Shear wave UT	Weld and HAZ	45-60 deg	Gel	Cracks at angles	Can miss parallel
Phased array UT (PAUT)	Weld and scan	Multi-element	Gel	Sizing, imaging	Replaces RT often
TOFD (Time of Flight)	Weld inspection	Paired probes	Gel	Excellent sizing	Poor at near-surface

Source: Inspection_NDE_Curriculum_v1.xlsx · Sheet: Volumetric

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