Had to pick between a 3/8 and a 1/2 inch backing bar for a 6 inch pipe weld

The print called for a 3/8, but the fit-up was a little sloppy, maybe a 1/16 gap in spots. I went with the 1/2 inch bar to give myself more room to fill, thinking it would save me time on the hot pass. Ended up creating way more heat input than I wanted, and now I'm worried about the stress on that joint. Anyone ever run into this on a tight schedule job?

2 comments

2 Comments

tyler_burns665d ago

Seen this same shortcut logic wreck a dozen other things. People grab the thicker bar, the bigger tool, the faster setting, trying to outrun a problem. You just trade one kind of stress for another. Now your weld is stressed from too much heat instead of a small gap. The rush to fix a small issue always makes a bigger one.

willow_martin4d ago

Exactly, it's a classic trap. That extra heat from the bigger bar can really change the cooling rate and shrink the grain structure wrong. You might not see a crack now, but that joint could be way more brittle down the line, especially with any vibration.

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