What is the procedure for welding stainless steel pipe with Shielded Metal Arc? Is it an acceptable practice to run an open root with, for example E308-15 electrode? I know the normal practice for root beads is with either TIG or MIG, but is it possible to get an acceptable root with SMAW? Any thoughts? While we're on the subject, I'd like some input on the preferred shielding gas for short arc MIG welding stainless pipe... 97 AR / 3 CO2? 90 HE / 7.5 AR / 2.5 CO2?
The SMAW might work if you had a backing ring.... Open root would be quite difficult skillwise and code wise.
Short circuit stainless? Why not consider GMAWP, RMD, STT or Cold Metal Transfer?
The tri-mix will short circuit... But fusion and control issues will never leave you. All the major pulse machines will weld very thin fillets with GMAWP with either 98/2 Ar/Oxy or 98/2 Ar/CO2
We have a procedure for stainless smaw pipe from root to cap,it was a requirement to get the job,another requirement for employment was a smaw only monel pipe cert as well.And yes it SUCKS! Have the kids try the stainless on for size,actually it's not that bad,nickel landing tight gap and circular manipulation of the puddle to get it in there.
Stone age process,I was told it's required because of lack of purgeability.
Just a curious question.
Stainless steel welding with SMAW I used back in my days of erector engineer, 40 years ago, when MIG and TIG welding were almost unknown here in South America.
Since then, a lot of water has passed under the bridges and MIG and TIG are common stuff all over the world. So, why do you want to use a method that is considered obsolete for welding stainless steel?
There must be a reason, of course. Just a curious question.
Giovanni S. Crisi
Sao Paulo - Brazil
P.S. I entirely agree with Lawrence.
I beleieve you would get a better result with a 16 coating electrode, but you need to add more info to make better suggestions.
We performed open root welding on boiler tubes using 5/64" diameter electrode. All rt.
Is it practical, no. Is it difficult, yes. Tie ins were the hardest part. Precise tapering of stops and remote amperge control were needed for me.
As with many things, wouldnt wanna do it now.
Gerald Austin
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