Direct Answer
A weld visual inspection per AWS D1.1 checks: weld size (fillet weld leg measured with a weld gauge), weld length (complete and continuous), surface condition (free from cracks, porosity, undercut, overlap, and incomplete fusion), crater fill at weld terminations, and correct weld profile (not excessively convex or concave). It is the most fundamental QC check and is performed on every structural weld before any NDT.
Full Explanation
AWS D1.1 Section 8 defines visual inspection acceptance criteria: (1) Cracks — not permitted. (2) Porosity — limited by weld type and service; CJP welds in tension have zero tolerance. (3) Undercut — maximum 1/32" for most welds; 1/16" for welds parallel to the primary stress. (4) Overlap — not permitted. (5) Weld size — must meet or exceed the specified size within -0/+1/4 leg. (6) Weld profile — crown convexity limited to the lessor of 1/8" or 20% of weld width. Visual inspection is performed by the special inspector after the weld has cooled to near-ambient temperature.
What This Means for Your Shop
Train your welders to perform their own visual inspection before the special inspector arrives — self-inspection before external inspection is standard quality practice. A welder who catches and repairs their own defects rarely fails special inspection.
Common Mistakes
Performing visual inspection immediately after welding while the weld is still hot. Some defects (hydrogen cracking) are not visible until the weld has cooled. AWS D1.1 requires visual inspection after the weld has cooled to near-ambient temperature for high-restraint conditions.
Recommended Process
Implement a 'pre-inspection inspection': your lead welder or QC inspector performs a visual pass on every weld before the special inspector arrives. Document findings. Repair any defects identified internally before the official inspection. This practice dramatically reduces inspection failure rates.