Difference Between Fillet Weld and Butt Weld

1. Fillet Weld:

   • Joins surfaces at an angle (e.g., T-joints, lap joints, corner joints).
   • Does not require edge preparation.
   • Triangular in cross-section and supports structural load transfer at angles.
   • Common for frameworks, bridges, and shipbuilding.

2. Butt Weld:

   • Joins two materials in the same plane (e.g., end-to-end, edge-to-edge).
   • Requires edge preparation (e.g., beveling) for penetration.
   • Provides high-strength, seamless joints.
   • Common in pipelines, pressure vessels, and critical structural applications.

Each weld type has distinct requirements for joint design, material preparation, and applications based on load and structural integrity