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Hey guys it's been a while since I've been on here. I gotta question for you professional pipe welders. In the last few months I've taken 4 6g tests. One chrome double extra cOmbo, 2 2 inch carbon combo monster coupons, and 1 monster tig all the way. All of them shot an bent except for the tig all the way. It had some indications in the side bends. I used 1/8 all the way at 165 amps except for the root. They let me retest with 3/32 wire and said that the failure rate for 1/8 s6 wire was up there. The second try had no issues whatsoever. Could it be bad wire? I usually run high amps and big wire with no issues. Just kinda bugging me.
Reply:I'm assuming that with the smaller rod, you were running less amperage, right?Only thing I can think of was maybe your gas coverage wasn't quite good enough? With 165 amps, you're carrying a big puddle. How big was the cup on your torch? How much argon were you flowing?i'll admit this is a long shot, since you'd most likely see any porosity that forms from a lack of shielding gas cover. But if the indications were small, maybe? Originally Posted by silveradomanHey guys it's been a while since I've been on here. I gotta question for you professional pipe welders. In the last few months I've taken 4 6g tests. One chrome double extra cOmbo, 2 2 inch carbon combo monster coupons, and 1 monster tig all the way. All of them shot an bent except for the tig all the way. It had some indications in the side bends. I used 1/8 all the way at 165 amps except for the root. They let me retest with 3/32 wire and said that the failure rate for 1/8 s6 wire was up there. The second try had no issues whatsoever. Could it be bad wire? I usually run high amps and big wire with no issues. Just kinda bugging me.
Reply:Well a dab, I believe it was at least an 8 cup. And yes I was running 130 with the small wire. The puddle looked the same, just the usual silicon, but it seemed like more than usual. The indications were right in the center of the side bends.
Reply:Well, it could have been the filler metal, but that seems like a long shot. Small indications in the center of the side bends...? There's just no way to say for certain what went wrong without more info and pictures. Could be small areas of lack of fusion/cold lap, or microporosity, or intermittent glass/oxide inclusions. All of these could be technique related or filler metal/contamination related. If I were bound and determined to figure it out, I'd run some more coupons at lower amperage, say 150 and 130 amps for the fill and cap. See if running cooler, with a smaller puddle fixed the issue, since running cooler with 3/32 filler rod fixes the problem. Maybe switch to a big gas lense, even though you shouldn't need one on mild steel, and try again with 1/8" rod and 165 amps?There's just no way I can think of to figure out what went wrong without some trial and error testing. Sorry that's not much help.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector |
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