How is the effective throat of a fillet weld defined?

How is the effective throat of a fillet weld defined?

• A. The shortest distance from the root to the face of the weld
• B. The length of the weld along the face
• C. The distance from the root to the toe
• D. The thickness of the base metal

Answer: (A)

The effective throat is the part of a fillet weld that actually carries shear load—the smallest cross‑section through the weld. It is defined as the shortest distance from the weld root to the face of the weld, measured perpendicular to the weld axis. This thickness determines the weld’s strength in shear. Choosing the shortest distance from root to the face correctly identifies the cross‑section that resists loading. The length along the weld face isn’t the critical dimension for strength, the distance from root to toe isn’t the cross‑section that carries shear, and the base metal thickness isn’t the weld’s throat.

The effective throat is the part of a fillet weld that actually carries shear load—the smallest cross‑section through the weld. It is defined as the shortest distance from the weld root to the face of the weld, measured perpendicular to the weld axis. This thickness determines the weld’s strength in shear.

Choosing the shortest distance from root to the face correctly identifies the cross‑section that resists loading. The length along the weld face isn’t the critical dimension for strength, the distance from root to toe isn’t the cross‑section that carries shear, and the base metal thickness isn’t the weld’s throat.