Why it matters
Weld symbol questions show up across layout and fabrication. The symbol tells you the weld type, which side it goes on, its size and any finishing. Read it in the same order every time and most of these questions get easy.
Key points
- The reference line is always horizontal. The arrow points to the joint.
- A symbol below the reference line means arrow side. Above means other side.
- The fillet weld symbol is a right triangle with its upright leg on the left.
- Size goes to the left of the symbol, length and pitch to the right.
- A flag at the junction of arrow and reference line means a field weld. A circle there means weld all around.
Study tip
Sketch the joint and mark which plate the arrow touches before you decide arrow side or other side.
Try these
A fillet weld symbol drawn below the reference line means the weld goes:
- On the other side
- On the arrow side
- On both sides
- In the field
Show answer
B. On the arrow side Below the line is always the arrow side.
A small flag where the arrow meets the reference line means:
- Weld all around
- Grind flush
- Field weld
- Back gouge
Show answer
C. Field weld The flag marks a weld made on site, not in the shop.
In "6 x 50-150" beside a fillet symbol, 150 is the:
- Leg size
- Weld length
- Pitch, centre to centre
- Throat
Show answer
C. Pitch, centre to centre Length comes first, then pitch.
Keep going
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