Shoutout to the old hand in Gary who showed me the tube rolling trick that stopped my leaks cold
I was on a boiler rebuild up in Gary, Indiana about 4 months back and kept chasing leaks on a 2 inch tube sheet. I must have re rolled 6 tubes twice and 3 of them still wept when we hydro tested at 150 psi. The foreman was getting hot about it and I was starting to think my roller was shot. An older guy named Dale who had been at it 30 years pulled me aside and showed me to roll in two passes, first at low torque to seat the tube, then crank it, and to always roll from the center of the sheet outward in a cross pattern. He also had me mark the tubes with soapstone so I knew which ones I had already hit. Did all 12 that way and not one weeped on the next test. Any of you run a two pass method or do you just send it on the first go? Curious if it changes much with thicker walls.
Two pass all day. Learned it from a guy named Reuben on a feedwater heater job in Hammond, 1 inch tubes, 14 gauge wall. He had me seat them at about half torque, go back around, then finish them off. The other thing he drilled into me was clean holes and a light coat of oil on the roller pins, because a sticky roller will lie to you on the torque. On thicker walls, like schedule 80 or heavy gauge, I give it three passes and a little more time on the seat, since the tube fights you more going in. Soapstone marks saved me too, nothing worse than losing track and double rolling one and stretching it.