Non-tubular sloped T-joint · Figure 5.4 and Table 4.2
How does a sloped T-joint change the required weld geometry?
For a non-tubular T-joint, measure the local dihedral angle Ψ between the connected members. When Ψ is below 60° but at least 30°, select the Table 4.2 Z-loss by angle band, process and weld position, then add that loss to the required effective throat to obtain the geometric throat target.
Apply the non-tubular rule
- Confirm that the members form a non-tubular T-joint and identify whether the weld is a fillet or groove detail.
- Measure the local dihedral angle Ψ where the weld is made. A curved connection may require checks at more than one local section.
- Below 30°, this Figure 5.4 detail is not prequalified. From 30° to below 60°, use Table 4.2 Z-loss. Outside that band, follow the applicable Figure 5.4 angle condition and project design; above 100°, the obtuse side has the specified Detail C preparation.
- For a 30° to below 60° joint, read Table 4.2 by the angle band, process and position category: vertical/overhead (V/OH) or horizontal/flat (H/F).
- Set geometric throat to required effective throat plus Z-loss. Keep the design throat input from the project; the code lookup does not design the connection.
Bounded example: 35° FCAW-G T-joint
Assume a non-tubular joint with Ψ=35°, FCAW-G, vertical welding, and a drawing that requires 6 mm effective throat. This places the joint in the 30°≤Ψ<45° band and the V/OH column. Table 4.2 gives Z=10 mm for this process and position.
| Input | Selected source value | Result |
|---|---|---|
| Local member angle Ψ | 35° | 30°–<45° band |
| Process and position | FCAW-G, vertical | V/OH column |
| Required effective throat | 6 mm, from the assumed drawing | Do not infer from Table 4.2 |
| Table 4.2 Z-loss | 10 mm | Geometric throat target = 6 + 10 = 16 mm |
For the same angle and process in H/F, the table value is 6 mm, so the geometric throat target would be 12 mm for the same assumed 6 mm effective throat. These calculations only translate a supplied design throat through the tabulated Z-loss; they do not establish weld leg dimensions or connection capacity.
Table 4.2 values for the two sloped-angle bands
| Ψ range | Process | V/OH Z-loss | H/F Z-loss |
|---|---|---|---|
| 45°≤Ψ<60° | SMAW | 3 mm | 3 mm |
| 45°≤Ψ<60° | FCAW-S or FCAW-G | 3 mm | 0 mm |
| 45°≤Ψ<60° | GMAW | Not listed | 0 mm |
| 30°≤Ψ<45° | SMAW | 6 mm | 6 mm |
| 30°≤Ψ<45° | FCAW-S | 6 mm | 3 mm |
| 30°≤Ψ<45° | FCAW-G | 10 mm | 6 mm |
| 30°≤Ψ<45° | GMAW | Not listed | 6 mm |
“Not listed” is not zero. Do not infer a value for an absent process/position cell. Use the corresponding US customary table column when the project is using US units; do not numerically convert the SI table row.
Keep the branches separate
- For 80°–60° and above 100°, obtain the required effective throat from the contract and show weld leg on the drawing. At angles above 100°, the obtuse side has a specified Detail C preparation.
- For a non-tubular sloped T-joint, Ψ is the member dihedral angle used with Table 4.2. It is not a groove angle.
- For tubular T/Y/K joints, Table 10.5 uses included groove angle φ. Do not substitute local Ψ or Table 4.2.
- The Z-loss correction does not choose weld size, process suitability, preheat, filler, structural capacity, or PQR coverage. Check those independently.
Basis and scope
Basis: AWS D1.1/D1.1M:2025 base edition plus registered July 28, 2026 base-edition errata; AMD1 is excluded. Contract-specified edition governs. Source provisions are Figure 5.4 and Table 4.2 with the Figure 5.4 angle-condition notes. The SI values shown here match the processed reference table; use the applicable code-unit table for an actual project.