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Warning: Had to pick between two different backing bar setups on a 3-inch thick pressure vessel weld.

We were doing a full circumferential weld on a big steam drum for a plant in Gary, Indiana. The spec called for a backing bar, and I had to choose between our standard copper bar and a new ceramic one the shop had just bought. The copper bar was a known quantity, but it can sometimes cause issues with penetration on thicker stuff. The ceramic bar was untested for us, but the rep swore it gave a cleaner root. I went with the ceramic, figuring it was worth a shot. The prep took a bit longer to get it clamped right, but man, the root pass came out perfect, no grinding needed. It saved us about an hour of cleanup time on that one seam. Anyone else run into a situation where switching to a ceramic backing bar actually paid off on a heavy wall job?
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3 Comments
averyc94
averyc9415d ago
Three inch wall thickness on a steam drum is no joke. That ceramic bar saving a full hour of cleanup is a huge win.
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the_riley
the_riley15d ago
That ceramic bar trick sounds like a game changer for thick material. @averyc94, did you have to adjust your heat settings at all to keep from shocking the ceramic on that three inch wall? I've heard mixed results on stuff over two inches where the heat sink effect is so big. Getting a clean break on the first try with no slag cleanup must have felt pretty good.
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the_faith
the_faith15d ago
Oh man, I wish I had your luck. Last time I tried something new like that, I spent more time cleaning up my mess than if I'd just stuck with the old way (it was a whole thing with the fit-up, don't ask). That's awesome it worked out so clean on such a thick piece.
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