Specimen Parameters
Material property. Structural steel: 400–550 MPa.
Effective leg size × sin(45°). For equal-leg fillet, throat ≈ 0.707 × leg.
Total continuous weld length along the joint.
OSHA-recommended minimum for structural joints: 3.0.
Enter parameters and compute.
The Math
Fillet Weld Load Capacity:
Safe_Load_kN = (0.707 × throat_mm × length_m × UTS_MPa) / SF
= (effective_area × ultimate_strength) / safety_margin
Where:
- 0.707 = sin(45°), geometric constant for equal-leg fillet welds
- throat_mm = effective load-bearing dimension
- UTS_MPa = ultimate tensile strength (Q76005)
- SF = safety factor (never below 3.0 for structural)
Grounding: This calculator implements the AWS D1.1 structural welding specification for fillet welds, using ultimate tensile strength (Wikidata Q76005) as the base material property. All outputs are conservative estimates; field verification required before load application.
Data Export: seam-calculator.json (machine-readable constants & formulas)
Data Export: seam-calculator.json (machine-readable constants & formulas)