Square groove weld
Two short parallel lines on the reference line: a square groove weld, one of the groove welds that join two members edge to edge.
This explains what a symbol specifies on a drawing. It isn't welding instruction, and a drawing's own notes and the governing code take precedence.
How to read it
A groove weld is made by depositing filler metal in a groove between two members to be joined. The square groove is one of the standard groove welds, alongside the V, bevel, U and J grooves. India's IS 813:1986, which draws on ISO 2553, calls the same weld a square butt weld.
More welding symbols
Sources
- Steelworker, Volume 1, NAVEDTRA 14250, 1996, Naval Education and Training Professional Development and Technology Center, U.S. Navy (Internet Archive), Chapter 3, Drawings and specifications
- Welding Theory and Application, TM 9-237, 1967, Department of the Army (Internet Archive), Glossary
- Scheme of symbols for welding, IS 813:1986, Bureau of Indian Standards (Internet Archive, Public.Resource.Org), Table 1
Last reviewed September 25, 2026 by Rory Hansen. How we research