Welding Symbols Spec Table
Welding symbols are a set of conventions for indicating welding method, geometry, and dimensions on engineering drawings. Per KS B ISO 2553, groove (butt), fillet, plug/slot, and resistance welds can all be precisely specified. Understanding the relationship between the arrow line, reference line, and symbol position is key to correctly reading and writing weld drawings.
Groove Weld
Groove Weld · 4 sizes
Fillet Weld
Fillet Weld · 1 sizes
Plug/Slot
Plug/Slot · 2 sizes
Resistance Weld
Resistance Weld · 2 sizes
Special
Special · 1 sizes
Supplementary
Supplementary · 2 sizes
Surface Finish
Surface Finish · 3 sizes
Site Symbol
Site Symbol · 2 sizes
Frequently Asked Questions
What is the difference between fillet weld and groove weld?
Fillet welds join two surfaces meeting at right angles with a triangular cross-section. Groove welds join prepared (beveled) edges with full penetration. Use groove welds for strength-critical joints; fillet welds for general structures.
What does "arrow side" and "other side" mean in weld symbols?
Symbols below the reference line (arrow side) indicate welding on the face the arrow points to. Symbols above the line (other side) indicate welding on the opposite face. Both sides shown means double (both-side) welding.