Back to NDT Exchange Global Open Academy Showcase🎓 Academies Directory
VTLevel I & II PracticalOnline / Self-Paced

Visual & Optical Testing (VT) of Welded Joints

Complete inspection guide for welding inspectors and fabricators covering weld terminology, joint preparations (Single-V, Double-V), visual inspection gauges (Cambridge, Hi-Lo), and AWS D1.1 / ASME IX code limits.

NDT Exchange Global Open Academy 24 Hours (Self-Paced) AWS D1.1 / ASME Sec IX / ISO 5817
Total Tuition & Exam Fee
100% FREE
⚡ Start Free Learning (Instant Access)

💡 Plain-English Summary (In Layman's Terms)

Beginner Friendly
No prior physics or engineering degree required — here is what this technique actually does in the real world.

Visual Inspection is the oldest, cheapest, and most important inspection method. Before running expensive X-rays or ultrasound scans, an inspector inspects the surface with their eyes, magnifying lenses, and precision steel gauges. Over 80% of dangerous weld flaws (like surface cracks, missing weld metal, or jagged undercut grooves) can be caught visually before an asset ever enters service.

What You Will Understand in Plain Terms:
✓Weld Anatomy: Learning the real anatomy of a weld—root, toe, cap, throat, and bevel gap—in plain terms.
✓Tool Mastery: How to use stainless steel inspection gauges to measure weld height, undercut depth, and plate alignment.
✓Flaw Hunting: How to spot dangerous defects like cracks and cold laps versus harmless surface blemishes.
✓Code Rules: Knowing the exact limits (e.g. "undercut cannot be deeper than 1mm") so you know when to reject or approve.
Common Defects You'll Learn to Spot (Everyday Terms):
🔍 Excessive Reinforcement (Too tall weld crown)🔍 Undercut (Groove melted into parent metal)🔍 Porosity (Trapped gas bubbles)🔍 Overlap (Weld rolling over cold steel without bonding)🔍 Linear Misalignment (Unevenly matched pipes)
Open AWS D1.1 Weld Flaw Visualizer

Course Syllabus & Training Modules

Structured curriculum designed according to ASNT SNT-TC-1A & ISO 9712 requirements with layman explanations.
1

Weld Terminology & Joint Geometry

💬 In simple terms: The anatomy of a weld seam: how joints are prepped and glued together with molten metal

Standard terminology for groove and fillet welds according to AWS A3.0 and ISO 2553.

Butt welds vs. Fillet welds: How plates are joined edge-to-edge vs. at right angles
Joint preparation: Root face, bevel angles, and gap spacing to let molten metal penetrate completely
Fit-up inspection: Checking that pipes and plates line up straight before the welder strikes an arc
Surface cleaning: Removing rust, mill scale, and grease so welds don't bubble with porosity
2

Precision Visual Inspection Tools & Gauges

💬 In simple terms: The inspector's toolbelt: ruler gauges, mirrors, and tiny cameras

Direct measurement methodology using mechanical gauges and optical magnification.

Cambridge Gauge: The all-in-one steel tool used to measure weld cap height, fillet throat, and bevel angles
Hi-Lo Gauge: Checking if two connected pipes are slightly misaligned on the inside or outside
Lighting & eyesight rules: Minimum 1000 lux illumination and viewing angle rules (never flatter than 30°)
Borescopes & RVI cameras: Using flexible endoscopic camera snakes to look inside un-enterable pipes
3

Weld Discontinuities & Surface Morphology

💬 In simple terms: Flaw identification: what healthy welds look like vs. rejectable weld failures

Differentiating rejectable weld defects from acceptable process surface conditions.

Undercut: A sharp ditch gouged along the weld toe that acts as a stress razor blade for fatigue cracks
Porosity: Swiss-cheese gas pockets trapped in the weld bead from wind blowing shielding gas away
Cracks & Crater Cracks: Why any crack—no matter how tiny—is an automatic immediate failure
Lack of Fusion (Cold Lapping): Molten metal poured onto cold steel without actually melting into it
4

Code Acceptance Limits & Inspection Reporting

💬 In simple terms: Pass or Fail? Applying structural steel and pressure piping code rulebooks

Evaluating test specimens against AWS D1.1 Table 6.1, ASME B31.3 Normal Fluid, and ISO 5817 Level B.

AWS D1.1 Structural rules: Building columns and bridges (static vs. vibrating bridge loads)
Maximum reinforcement: Why making a weld too thick actually makes it weaker by concentrating stress
Writing the report: How to document inspected weld IDs, welder stamp numbers, and exact defect locations
Non-Conformance Reports (NCR): Mapping out where repair grinding and re-welding must occur

Course Instructor

Sarah Jenkins, CWI / Level III

Certified NDT Level III inspector with over 15 years of field inspection and industrial training experience.

Hosting Academy

NDT Exchange Global Open Academy

Worldwide (Digital Learning)
admissions@ndtexchange.com
Connected Exam Engine

Practice VT Qualification Exam

Test your knowledge on 185+ verified questions, ASME/AWS code explanations, and SNT-TC-1A composite pass score calculator before sitting for your official academy exam.

Launch VT Exam Simulator