Finally figured out why my boiler tubes kept cracking after 3 years

I used to just crank the torch and go, but after a guy in Tulsa showed me his preheat method using a temp stick, I realized I was rushing the warmup. Now I take an extra 10 minutes per tube and haven't had a single failure since. Anyone else have a trick that cuts down on cracking?

3 comments

3 Comments

samflores1mo ago

Man I totally get that! I was reading some old boiler forum posts from like 2009 and this guy who used to work on naval ships said they'd heat the whole tube area to 300 before even striking an arc. He called it "soaking" the metal. Tried it on a job last month with a big drum repair and the difference was night and day. The weld just flowed nicer and I didn't see any microcracks in the heat affected zone later. Makes you wonder how many failures we could avoid if we all just slowed down a little.

brianm661mo ago

Yeah preheat makes all the difference, I started letting mine sit at 200 for a full five minutes before welding and never looked back.

lily571mo agoMost Upvoted

I don't know, "night and day" seems a little strong. I've been welding on and off for thirty years and I'll admit preheat helps, especially with thicker stuff, but some folks act like it's the secret to life itself. I've seen guys skip it entirely on repair work and the welds held up just fine for years. Not saying it's useless, just that maybe we get a little carried with the drama sometimes.