27 Welding Symbols
Welding symbols are used to record the specifics of a given weld. They are most often found on shop or fabrication drawings. AWS A2.4 – Standard Symbols for Welding, Brazing, and Nondestructive Examination is the official standard for all elements of the welding symbol.
The basic components of a welding symbol are the reference line (always required), arrow line, and tail. The reference line is always horizontal and forms the base of the welding symbol. The arrow line points to the line or lines on the drawing which clearly identify the proposed joint or weld area. One end has an arrow pointing towards the drawing and the other connects to one end of the reference line. The tail, the right-angled line on the other end of the reference line, is used to record any supplementary information about the weld, such as welding or cutting processes, specifications, or procedures.
When talking about a welding symbol, the arrow side is the side of the reference line where the arrow line is, while the other side of the reference line is simply called the other side. Any symbolism on the arrow side of a welding symbol applies to the part of the drawing that the arrow line is pointing at. Any symbolism on the other side applies to the other side of the same area, which the arrow line is not pointing at.
Other symbolism used in welding symbols includes:
- A circle around where the arrow and reference lines meet: welding all around the joint
Welding all around the joint - A black, triangular flag where the arrow and reference lines meet: field weld
Field weld - A break in the arrow line: arrow side must be side that receives beveling or other required preparations
Arrow side receives beveling or other preparations
- A plain triangle off the reference line: filet weld
Filet welds on arrow side and other side - A filled rectangle off the reference line: plug or slot weld
Plug or slot weld on arrow side
The relative locations of the symbols along the reference line can have meaning, such as staggered or intermittent welds along the welding area. Welding symbols can also include numbers to accurately convey information such as the depth of a bevel, the length of a weld, the number of spot welds to complete in an area, etc. If you’re not sure what something on a welding symbol refers to, always look it up.
