A CWI is overseeing a visual inspection (VT) of a newly fabricated structural steel beam. The inspector notes that the weld reinforcement on a groove weld exceeds the maximum allowable height specified in the welding procedure specification (WPS). This condition is categorized as:
- AInsufficient throat.
- BExcessive convexity.
- COverlap.
- DUndercut.
Show answer & explanationAnswer & explanation
Correct answer: B. Excessive convexity.
Excessive convexity refers to a fillet weld or groove weld that has a surface curve that is too pronounced, exceeding the specified limits. In a groove weld, this is specifically called 'excessive reinforcement' where the weld metal extends too far above the surface of the base metal. Option C, 'Excessive convexity', is the broader and more encompassing term for this condition that applies to both fillet and groove welds when their profile exceeds specified limits.
Why the other options are wrong
- A. Insufficient throat refers to a fillet weld that does not meet the specified minimum throat dimension, usually due to a concave profile or insufficient weld size, not excessive height.
- C. Overlap is when weld metal extends beyond the toe or root of the weld without fusing.
- D. Undercut is a groove melted into the base metal adjacent to the weld toe or root.
VT - Excessive Convexity/Reinforcement
Excessive convexity (for fillet welds) or excessive reinforcement (for groove welds) is a discontinuity where the weld metal extends too far above the theoretical weld face or base metal surface, exceeding specified limits.
- Weld profile is too high.
- Exceeds WPS or code limits.
- Can lead to stress concentrations.
- Often visually apparent.
Memory trick: Too high, too low, or just right.