Sub-arc

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Anybody have advice on wire/flux combinations? This is a 42" od pipe, 1" wall, 60 degree double bevel joint with 3/8 backing strip and 3/8 gap.
Reply:3/8 " th gap is pretty wide,  Our gaps are 0-1 mm with 4-5mm land, We use ESAB 1204f34  81  5/32  wire and ESAB 10.72 flux  with AC/DC around DCEP 625 amps 24 volts 40 IPM AC 575 amps 25 volts 40 IPM for the root And increase volts, amps and decrease IPM For remainder of welds. WE also run AC/AC on some parts with a Lincoln SUB 1000. Hope this helps
Reply:3/8 did turn out to be pretty wide for a root gap, I poked a hole or two on the practice stock. But that's what it said in the procedure, so we went with that until it could be shown to be impractical.  We ended up with 1/4 root gap, no land, 60 deg. included knife bevel and 3/8 backing. Lincoln wire L61 with Lincoln 860 flux. We tried 2 other fluxes, 888 and 980, both of which I liked better than the 860, which tended to bind up on the root pass. I actually had to stop the pipe on several occasions to chip out the spent flux. (Any solution for that, by the way?) Put the root in at 400 amps, 32-33 volts and 15 ipm. Hot pass at 500 amps, 34 volts, 15 ipm and all subsequent passes at 600 amps 34-35 volts 22 ipm. If I ended up with a shallow shape for the cover, I reduced the amperage back to 500, 33 volts and left the travel at 21-22 ipm. Thanks for your input. I had almost given up! I guess submerged arc is not as common as I had thought. In case anybody needs any more info on this, I can tell you a whole lot about what NOT to do!
Reply:Oops... hot pass at 32-33 volts... not 34.