Cracked a boiler tube right before a pressure test, had to back purge the whole section again

Was doing a retube job over in Gary last week on an old Cleaver Brooks unit, got everything welded up and then found a hairline crack near the backsheet while doing the visual. Had to cut out three tubes and redo them because the crack ran into the adjacent ones from the heat stress. Took me most of the afternoon to back purge and re weld, definitely learned to check my fit up more careful before laying beads. Any other boilermakers run into tube cracking from poor alignment?

3 comments

3 Comments

garcia.tyler27d ago

Heating the backsheet with a rosebud torch before welding stopped my cracks cold.

the_mary27d ago

Wonder if the heat affects the plasticizer migration over time...

terryk1020d agoTop Commenter

Yeah @the_mary I was skeptical too but tried it and it worked for me.