What Is a Weld Profile?
A weld profile is the cross-sectional shape of the finished weld bead. It describes whether the weld face is flush with the base metal, humped above it (convex), or dipped below it (concave). Profile matters because it directly affects fatigue life, stress concentration, and the ability to perform nondestructive examination.
D1.1:2025 Clause 7.23 requires that all welds meet the visual acceptance criteria of Tables 8.1 or 10.14 and be free from cracks, overlaps, and the unacceptable profile discontinuities shown in Figure 7.4, Table 7.8, and Table 7.9.
Acceptable vs Unacceptable Profiles
Figure 7.4 classifies weld profiles into three categories: desirable, acceptable, and unacceptable. The classification varies by joint type:
Groove welds (butt joints): Reinforcement must be within the limits of Table 7.9 Schedule A. The weld face should have a gradual transition to the base metal surface. Excessive reinforcement, abrupt transitions, and overlap are unacceptable.
Fillet welds (T-joints, lap joints, inside corners): The face may be slightly convex, flat, or slightly concave per Clause 7.23.1. Convexity limits are set by Table 7.9 Schedule C. Excessive convexity concentrates stress at the weld toes and is unacceptable. Insufficient throat (concavity that reduces the effective weld size below the minimum) is also unacceptable.
Outside corner fillet welds: Governed by Schedule D, which sets convexity at half the thickness of the thinner exposed edge dimension.
Convexity Limits — Tables 7.8 and 7.9
D1.1 uses four convexity schedules defined in Table 7.9. Table 7.8 maps each joint type and weld type to the applicable schedule and Figure 7.4 diagram.
Schedule A — CJP Groove Welds (Butt Joints)
| Plate Thickness (t) | R min. | R max. (reinforcement) |
|---|---|---|
| t ≤ 1 in [25 mm] | 0 | 1/8 in [3 mm] |
| t > 1 in, ≤ 2 in [50 mm] | 0 | 3/16 in [5 mm] |
| t > 2 in [50 mm] | 0 | 1/4 in [6 mm]* |
*For cyclically loaded structures, R max. for t > 2 in is 3/16 in [5 mm].
Schedule B — CJP Groove Welds (Corner and T-Joints)
| Plate Thickness (t) | R min. | R max. | C max. (convexity/concavity) |
|---|---|---|---|
| t < 1 in [25 mm] | 0 | unlimited | 1/8 in [3 mm] |
| t ≥ 1 in [25 mm] | 0 | unlimited | 3/16 in [5 mm] |
Schedule C — Fillet Welds (Most Common)
| Weld Face Width (W) | C max. (convexity) |
|---|---|
| W ≤ 5/16 in [8 mm] | 1/16 in [2 mm] |
| W > 5/16 in, < 1 in [25 mm] | 1/8 in [3 mm] |
| W ≥ 1 in [25 mm] | 3/16 in [5 mm] |
These limits apply not only to the total face width of the completed weld but also to the width of an individual surface bead on a multi-pass weld per Clause 7.23.1.
Concavity: There is no restriction on concavity as long as the minimum weld size (considering both leg and throat) is achieved per Table 7.9 footnote b.
Schedule D — Outside Corner Fillet Welds
For outside corner fillet welds, maximum convexity C = t/2, where t is the thickness of the thinner exposed edge dimension. See Figure 7.4F for where Schedule C vs D applies.
What Does "Flush" Mean?
Per Clause 7.23.3.1, welds required to be flush must be finished so as to not reduce the thickness of the thinner base metal or weld metal by more than 1/32 in [1 mm]. Remaining reinforcement must not exceed 1/32 in [1 mm] in height and must blend smoothly into the base metal surfaces with transition areas free from undercut.
All reinforcement must be removed where the weld forms part of a faying or contact surface.
"Flush" does not mean perfectly flat. It means within 1/32 in of the base metal surface with a smooth, undercut-free transition. Over-grinding that thins the base metal below this tolerance is a defect.
Surface Finish Requirements
Per Clause 7.23.3.2, where surface finishing is required, surface roughness values shall not exceed 250 microinches [6.3 micrometers] per ASME B46.1.
For cyclically loaded structures, finishing must be parallel to the direction of primary stress, except that a final roughness of 125 microinches [3.2 micrometers] or less may be finished in any direction.
Chipping and gouging may be used as initial material removal methods, provided they are followed by grinding or machining to achieve the required surface roughness.
Grinding and Repair Methods
Per Clause 7.25, weld metal or base metal may be removed by machining, grinding, chipping, or gouging. The work must be done so that adjacent weld metal or base metal is not nicked or gouged. Oxygen gouging is permitted only on as-rolled steels.
The Contractor has the option of either repairing an unacceptable weld or removing and replacing the entire weld per Clause 7.25.1. The repaired or replaced weld must be retested by the original method with the same acceptance criteria.
Peening may be used on intermediate weld layers for control of shrinkage stresses per Clause 7.26, but no peening is permitted on the root or surface layer of the weld or the base metal at the edges of the weld.
Visual Inspection Criteria — Table 8.1
Table 8.1 is the master visual inspection acceptance criteria table. Profile requirements are item (4): weld profiles must conform to Clause 7.23. This applies to both statically and cyclically loaded nontubular connections.
Related Table 8.1 items that interact with profile acceptance:
| Item | Criterion | Static | Cyclic |
|---|---|---|---|
| (4) Weld Profiles | Conform to Clause 7.23 | Required | Required |
| (6) Undersized Fillet | Undersize allowed per schedule (e.g. ≤ 1/16 in for 1/8-3/16 fillet) | Max 10% of length | Max 10% of length |
| (7) Undercut | ≤ 1/32 in for material < 1 in thick (static) | 1/32 in general | 0.01 in transverse to stress |
A weld that passes the convexity schedule but has excessive undercut at the toes still fails visual inspection. Profile, undercut, and undersizing are checked together as part of the same Clause 8.9 visual examination.