Sub Arc Flux

Date 05-04-2011 20:03

Catch pan with a screen or expanded metal on the floor. That's the cheap way. Or you can always start pricing vacuum recovery/recirculation systems. But you still need a catch pan........
I've sub arced on 240" vessels, and you still have a pile of flux on the floor at the end of the day.

By welder5354 (**)

Date 05-05-2011 01:43

Hi, i was referring to welding of smaller diameter pipe, (e.g. 6 inch)
Do you use anything in the V-groove to keep as much flux,
as possible around the nozzel and wire.

By RonG

Date 05-05-2011 16:03

We use a flat Cooper bar (1/4" x 1" x roughly 4") attached to a rod for a handle to hold the flux back (down hill side opposite direction of rotation). It works well.

By js55

Date 05-05-2011 18:25

SAW isn't the most productive process for 6".

By welder5354 (**)

Date 05-05-2011 21:24

I'm talking 6 in...XXS pipe.
With teh sub arc, that should be a 20 min job..Fill and cap.
First pass GMAW (STT) and another pass with FCAW and the
remainder SAW.

By js55

Date 05-06-2011 12:00

Except that by the time you get the SAW head positioned and verify everything is ready to go you could have two more layers in with FCAW. Plus you lose productivity with flux management with SAW. Something often overlooked and the jist of the OP.
Also, you can't take full advantage of the higher deposition rates on smaller diameters which is the biggest advantage of SAW. You can't crank the amps up too far or your beads hump from being wet while rotated off the back side where gravity is not your friend.
I could see perhaps them being more equal on that diameter if you had impact regimes as a concern. This would limit the amount of metal you can carry with FCAW, and minimize its weave advantage as well. Especially if you were running an electrode extension on SAW. I'd be tempted to use SAW then. Electrode extension technologies have not been perfected for FCAW yet as far as I know.