Read the whole symbol
Every wrong answer here differs in one detail only, so read all of it. Some questions ask you to type a number you have to work out. Get 10 right to finish.
Which description matches this symbol exactly?
Read it in this order
- Side. Below the line is the arrow side in AWS. In ISO System A the solid line is the arrow side and the dashed line the other side.
- Weld type. The shape of the symbol: triangle for a fillet, V, bevel, two lines for a square butt or groove.
- Size, to the left of the symbol. In ISO the letter tells you what was measured: a is the throat, z the leg.
- Length and pitch, to the right. No number means the full length of the joint.
- The bend. A circle means all around. A flag means field weld, made on site.
Numbers you have to work out
Some questions have no answers to pick from. Type the number, then press Check. Plain numbers are fine, and so are fractions like3/8. If you are stuck after two tries, you can show the answer and move on.
- AWS gap between welds. 2-6 means 2 in welds at a 6 in pitch, center to center. The bare metal between two welds is 6 - 2 = 4 in.
- ISO leg from throat. a5 is a 5 mm throat. The leg is about 5 x 1.414 = 7.1 mm, so about 7 mm.
Questions
- In what order should I read a welding symbol?
- Side first (where the weld symbol sits on the reference line), then the weld type, the size on the left, the length and pitch on the right, and last the marks at the bend: a circle for all around and a flag for a field weld.
- How do I find the gap between intermittent welds?
- In AWS A2.4 the pitch is measured center to center, so the bare metal between two welds is the pitch minus the weld length. 2-6 leaves 4 in between welds.
- An ISO fillet says a5. How big are the legs?
- a is the throat. On an equal-leg fillet the leg is the throat times 1.414, so a5 needs legs of about 7 mm.
Explained in our own words. For the full rules, see AWS A2.4:2020 and ISO 2553:2019.