Started out skeptical about pre-heating my SMAW electrodes, now I swear by it

For the first five years I was a boilermaker, I never bothered with rod ovens. I figured if the rods weren't wet, they were fine to weld with. But last winter on a job up in Gary, Indiana, I kept getting porosity in my 7018s on a pressure vessel repair. The foreman finally made me spend 20 minutes heating a batch to 350 degrees. The difference was night and day, no more pinholes, and my weld test passed first try. I still see guys out there pulling rods straight from a damp toolbox, and I just cringe. Has anyone else had a similar wake up call with something they wrote off as unnecessary?

2 comments

2 Comments

the_logan1mo ago

I remember back in '09, we had a job welding handrails for a county bridge in a rainstorm. The rods were sitting in a bucket with an inch of water at the bottom. The old-timer I was working with just shook his head, tossed them in a makeshift oven we rigged out of a steel drum and a propane torch. Took us an extra hour to dry them out before we could even start, but that weld held for years. Funny how you think you're saving time skipping the prep, but really you're just setting yourself up for a headache later. Some lessons you gotta learn the hard way I guess.

taragrant1mo ago

Funny timing, I was just reading an article about how moisture in welding rods can cause hydrogen embrittlement. Said it's one of those hidden failures that shows up way later when you least expect it. That old timer probably saved you a massive headache down the road.