SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/weld-symbol-field-flag

A flag at the arrow and reference line junction means the weld is made where?

In the field, on site.

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  1. In the shop
  2. In the field, on site ✔
  3. Underwater

Why: The field weld flag means the welding happens on site during erection. No flag means it is done in the shop.

Huh, didn't know that: Older drawings may show a filled black circle instead of a flag.

The dad joke
What's the best part about living in Switzerland? I don't know, but the flag is a big plus.
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References

Answer: In the field, on site. The field weld flag means the welding happens on site during erection. No flag means it is done in the shop.

  1. How to Read and Understand Weld Symbols (Miller) www.millerwelds.com/en-US/resources/knowledge-hub/welding-basics/how-to-read-and-understand-weld-symbols
    The flag growing out of the junction of the reference line and the arrow is present when completing the weld in the field.
    Checked 2026-10-10.

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