Stop trusting impact drivers for boiler tube plugs, here's why

I watched a 4th year apprentice destroy two plugs last week on a 60-inch drum because he zipped them in with an impact. The torque curve on those things is way too aggressive for brass ferrules, you'll crush the seat before you feel any resistance. I've been hand tightening with a ratchet and then a 2-foot cheater bar for the last 12 years down in Houston and I've never had a leak at startup. Has anyone else seen this biting people on hydro tests, or am I just working with heavy-handed guys?

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sullivan.quinn17d agoTop Commenter

Hand torque is solid but a 2-foot cheater bar on a 5/8 inch plug is still way past what the brass seat is rated for. The ferrules crush at around 40 foot pounds, and you're easily hitting 60 plus with that bar. I've seen guys with years in the trade blow out the same way, just slower, and blame the plug manufacturer instead of their own arm strength. A calibrated torque wrench on the ratchet is the only thing that keeps it repeatable, and even then you back off a quarter turn after seating.