Weld symbol
Weld all around symbol
A circle at the elbow where the leader meets the reference line means the weld continues completely around the joint, wrapping every side of the attachment rather than stopping at a corner.
Reads asArrow side: fillet weld, 1/4 size.
How to read it
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.
Where each dimension goes
- Circle at the elbow
- Applies to every weld symbol on that reference line: continue the weld around the joint's whole perimeter.
- Position on the leader
- It sits at the junction of the leader and the reference line, never against the weld symbol itself.
- Relationship to length
- An all-around weld has no length dimension, because the perimeter of the joint is the length.
- Combination with the field flag
- Both can share the elbow. They are separate instructions and neither implies the other.
Worked examples
Each one is a drawing, the sentence it comes out as, and then the mark-by-mark account of why. Read the sheet first and say the sentence yourself before you look down.
Example 1: All-around fillet on a post
TitleAll-around fillet on a postRefWeld all aroundEx1 / 2Reads as
Weld a 5/16 fillet all the way around the base of the post.
Which mark says so
- fillet symbolBelow the reference lineA fillet weld on the arrow side of the joint
- 5/16Left of the symbolLeg size of the fillet
- Circle at the elbowWhere the leader meets the reference lineWeld all the way around the joint
The circle at the elbow applies to the fillet triangle on the reference line, so the weld follows the whole perimeter of the attachment rather than a single face.
And what it does not say
- No length is given, so each weld runs the full length of the joint.
- Nothing sits above the reference line, so the far face of the joint stays bare.
Example 2: All around and in the field
TitleAll around and in the fieldRefWeld all aroundEx2 / 2Reads as
Weld 1/4 fillets both sides, all around, on site rather than in the shop.
Which mark says so
- fillet symbolBelow the reference lineA fillet weld on the arrow side of the joint
- 1/4Left of the arrow-side symbolLeg size of the fillet
- fillet symbolAbove the reference lineA fillet weld on the far side of the joint
- 1/4Left of the other-side symbolLeg size of the fillet
- Circle at the elbowWhere the leader meets the reference lineWeld all the way around the joint
- Flag at the elbowWhere the leader meets the reference lineField weld - made on site rather than in the shop
The circle and the flag share the elbow and act independently: the circle carries the weld around the perimeter and the flag says the work happens at the erection site.
And what it does not say
- No length is given, so each weld runs the full length of the joint.
Common mistakes
- Stopping and restarting at every corner instead of turning them, which leaves craters where stress concentrates.
- Reading the circle as applying to only one of several weld symbols on the reference line.
- Adding a length dimension to an all-around weld, which contradicts the instruction.
- Confusing the elbow circle with a spot weld symbol placed on the reference line.