Bad [misdrawn, or 'made-up'] symbol. Two rolled angles turned into HSS tube steel require 'flare-bevel' corner welds, full length, both corners. Flare Bevel because the tips of angle are rounded, not square or at a fixed angle.

I think the tail symbol you identify is the author indicating that the weld should occur on the three sides of the horizontal leg of the angle.
So you would have a pure 3-sided "U" shaped weld once done.

This assumes that the angle is shorter than the width of the tube. If the angle extends out wider than the width of the tube, you would not want to have a continuous weld across the discontinuous corner (i.e. an overhead weld on the bottom of the tube crossing upward at the corner and becoming a downward weld on top of the angle leg).

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I'd request a legend from whoever put that symbol up.

FWIW: one of the causes of the Hyatt Regency skywalk collapse & disaster was a poorly designed weldment that had two large C-channels being welded into a box beam. The designer treated the radiused flange tips as if they were square. Then he failed to indicate that a backing bar would be required to achieve the full-penn weld that he used for the calc's. Since backing was not on the print, no backing was used. The welds ended being 'face welds', partial-penn flare-bevel welds with a built-in notch effect in the root of each entire weld. Proper, understandable symbols actually matter a lot.

yeah, having to guess means the drawing is bad. if no one owns up to putting the symbol on, then they're giving you a revision. no revision, no construction

The only thing more difficult than conveying the importance of AWS A2.4 is finding a detailer who knows how to follow it...

It is what I refer to as a "Kalvin Kline" welding symbol. If you can't find a standard symbol that meets your need, make one up.

The problem with KK welding symbols is they do not meet AWS A2.4 nor any other recognized standard. They can easily confuse the person trying to interpret the intent, they can hold up production, and generally are a poor way of conveying the welding requirements.

"When in doubt, sketch it out."

Best regards - Al

Only thing worse is a Low Budget Detailer who subs his work out to "unknown" parties in the 2rd World...not only wrong D1.1 symbols but call outs and mis-spelled directives?

Time for an RFI including a bold font "WTF is this" as well..?? LOL
Not once in 37 yrs (23 as a CWI), have I ever seen that particular symbol...I'm sure it means something to the guy that drafted it..but nothing the the rest of the planet would know.

Stk

I've seen that kind of symbol many times over 32 years...

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