Weld all around symbol

The all-around circle is drawn at the elbow, the point where the arrow's leader meets the reference line. It is not attached to any one weld symbol, which is exactly the point: it modifies the entire instruction on that reference line, so every weld symbol on the line continues around the joint.

What counts as around depends on the joint. On a round tube welded to a plate it means a continuous ring. On a square post it means welding all four faces and turning the corners without stopping. On an irregular attachment it means following the joint's whole perimeter back to the start. The circle says continue; the geometry of the part says where.

Turning the corners is where the instruction actually costs something. Stopping and restarting at each corner leaves craters, unfused starts, and a stress raiser at exactly the point where load concentrates. Fabricators who honour the circle plan their stops so restarts land partway along a face, and they wrap past the start point to close the ring properly.

The circle and the field flag often appear together at the same elbow, and they are independent instructions: one says where the weld goes, the other says where the welding happens. Reading one and missing the other is common on crowded drawings, so it is worth checking the elbow deliberately rather than jumping straight to the weld symbol.