VT
Visual Testing
Summary
The most basic and widely used NDT method. Direct or remote visual examination of welds and materials for surface discontinuities.
Scope
Surface examination of welds, base materials, and fabricated components.
Key Requirements
Governing Standards
- ASME Section V, Article 9
- AWS D1.1 Clause 6
- ISO 17637
- EN 13018
What It Detects
- Cracks (surface-breaking)
- Undercut
- Porosity (surface)
- Incomplete fusion (surface)
- Excessive reinforcement
- Misalignment
Limitations
- Surface discontinuities only
- Dependent on inspector skill and lighting
- Cannot detect subsurface defects
Required Certifications
- AWS CWI
- CSWIP 3.0/3.1/3.2
- ASNT Level II VT
- ISO 9712 Level 2 VT
Applicable Materials
Carbon SteelLow Alloy SteelStainless Steel 304Stainless Steel 316AluminumDuplex Stainless SteelNickel Alloys
Applicable Processes
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