Why does nobody talk about the real failure rate on those quick-set patch kits?

I was reading an old industry report from the National Board of Boiler and Pressure Vessel Inspectors last week, and a stat jumped out at me. It said that in a study of over 200 emergency repairs on low-pressure steam systems, temporary patch kits failed within six months about 40% of the time. I've always heard guys swear by them as a solid short-term fix, but that number seems way too high to ignore. In my own work, I've seen maybe one or two come back, but I guess I just got lucky. The report broke it down by cause, and most failures were from improper surface prep or using the wrong kit for the temperature. It makes me think we should be way more careful about recommending them, even for a quick job. Has anyone else had a patch fail on them, and what did you switch to instead?

2 comments

2 Comments

elizabeththomas1mo ago

Did the report mention if the failures were mostly on wet or dry steam lines?

hugo_moore1mo ago

Oh man, they totally skipped that part. Classic. The whole report is like twenty pages on metallurgy and then just shrugs about the actual water. It's all "stress corrosion cracking this" and "cyclic fatigue that." You'd think for a steam line report they'd mention steam. Guess we're supposed to just guess.