MSS SP-75 sect 14.4.4 butt-welds

[Itsnotgoinganywhere]

14.4.4 of MSS SP-75 2014 wants sub arc welds with one pass from inside unless it's inaccessible "then, a manual or machine root bead may be employed..."
Does that language exclude semi-automatic processes (eg GMAW and FCAW) for the single sided root bead?

Secondary to that question, I don't see why GMAW/FCAW would not be permitted for a shop-built fitting. Are people actually doing all of their root welds with SMAW or GTAW still? How do you get any productivity from a shop running like this?

 

[DVWE]

Does that language exclude semi-automatic processes (eg GMAW and FCAW) for the single sided root bead?

Yes it does. However, I have seen fittings manufactured to this spec that I am certain are GMAW welds. Keep in mind, when you take the torch or welding gun out of the welder's hand and put it on a machine controlled arm, it is then considered a machine welding process.

Are people actually doing all of their root welds with SMAW or GTAW still?

I have seen roots done with GTAW, but not done manually. They are also set up on machine controlled equipment, so a machine welding process.

 

[Itsnotgoinganywhere]

Thanks for the reply. I figured as much. Ugh. Guess I'll be looking into some boom-mounted options.