Some people seem to think they're psychic and have ESP in these matters... ;) "Tiny Bubbles! ;)" Hmmm...  "I can visualize... Ummm never mind!!! :("
Must be the meds kicking inright about now..... :) :) :)

Respectfully,
Henry

I suspect you will find that the pipe was not susposed to be welded as you described. (GTAW)
6.1.3 Welded (WLD) pipe shall be made using an automatic
welding process with no addition of filler metal during the
welding process.

It's not unusual to see flash from the ERW or other methods, but Do remember this part of the specification:

"15. Repair by Welding
15.1 For welded pipe whose diameter equals or exceeds
NPS 6, and whose nominal wall thickness equals or exceeds
0.200, it is permitted to make weld repairs to the weld seam
with the addition of compatible filler metal using the same
procedures specified for plate defects in the section on Repair
by Welding of Specification A 999/A 999M.
15.2 Weld repairs of the weld seam shall not exceed 20 % of
the seam length.
15.3 Weld repairs shall be made only with the gas tungsten arc
welding process using the same classification of bare filler
rod qualified to the most currentAWS Specification A5.9 as the
grade of stainless steel pipe being repaired and as shown in
Table 5. Alternatively, subject to approval by the purchaser,
weld repairs shall be made only with the gas tungsten-arc
welding process using a filler metal more highly alloyed than
the base metal when needed for corrosion resistance or other
properties."

If your seeing a weld that looks like GTAW with filler added, then the only legit use of GTAW standard method is for repair.
If it is repair, then you have to go to para 15.2.

I had a run in with a manufacture that thought the 20 percent was inclusive. I.E. with two seams, they could have 40 percent repair on one side if they were clean on the other seam. It doesn't work that way, and the manufacture had to eat a few spool pieces.