Surface NDE

Module from the Inspection and NDE Curriculum curriculum.

Module 2 - Visual and Surface NDE · Learning Objectives · 1. Perform visual examination per ASME V Article 9 and ACCP Level II · 2. Conduct liquid penetrant (PT) per ASME V Article 6 · 3. Perform magnetic particle (MT) per ASME V Article 7 · 4. Select technique based on material (PT for SS, MT for CS) · 5. Apply acceptance criteria from governing code (B31.3, VIII) · PT and MT Technique Selection

Method	Principle	Material	Surface Prep	Sensitivity	Common Defect
Visible dye PT	Visible dye in cracks	Non-porous, non-ferromag	Clean degreased	Surface cracks 0.004+ in	Cracks, porosity
Fluorescent PT	UV-fluorescent dye	Non-porous	Very clean	Most sensitive	Fine cracks
Wet continuous MT	Magnetic field and particles	Ferromagnetic	Clean, degreased	Surface + shallow subsurface	Surface cracks
Dry continuous MT	Magnetic powder	Ferromagnetic	Clean, dry	Moderate	Surface cracks
Fluorescent wet MT	Fluorescent magnetic particles	Ferromagnetic	Clean	High sensitivity	Surface cracks
AC yoke MT	AC magnetic field	Ferromag	Minimum prep	Surface only	Field inspection
WFMT (wet fluorescent)	Combines above	CS + CrMo	Clean + dark area	Highest surface	Stress corrosion
ACFM	AC field measurement	CS + CrMo	Minimal	Crack sizing	Sizing cracks under coating

Source: Inspection_NDE_Curriculum_v1.xlsx · Sheet: Surface NDE

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