It would depened on the skill of the welder.
I have welded gas pipe before, BUT it was 6" in diameter and XXX strength, (XXX is aproxamatily 3/8" thick walled).
Very high pressure, and X-ray tested before use.
On a TD or TTT I can not recomend it's usage as the vibration would shorten the life expentcentcy of said pipeline.
Just my $0.02 cents worth from past experiences, YMMV !
Stay safe, and have fun !!!
Wanna Be
Lynn
This nation will remain the land of the free only so long as it is the home of the brave.
~Elmer Davis
"Well, if you can't believe what you read in a comic book, what can you believe?" ~ Bullwinkle J. Moose
Also I am a professional spelling butcher.. I don't carry a dictionary and my spell check is broke!!