Question about tube rolling: I was expanding tubes wrong for 3 jobs straight and a guy named Dale finally said something
So I came up in a shop in Beaumont and the old guy who trained me always said let the roller do the work. Except he never actually showed me the feel for it. I was just cranking until it sounded right, you know? Ran probably 40 tubes on a boiler at a paper mill outside Texarkana doing it that way.
Then this fitter named Dale watches me for maybe two minutes and goes "son, you're expanding past the tube sheet, feel that?" Sure enough the tube was bulging on the back side of the sheet. I had no idea. I was going off sound instead of watching the roller torque and feeling when it tightens up. Had to cut out 12 tubes and redo them.
Nobody ever told me to mark the tube depth on the roller housing with soapstone so you can see how far in you are. Dale showed me that in like 30 seconds.
Whats the trick you all use to know when a tube is rolled enough? Do you go by feel, torque, gauge, or something else? I want to hear how other people learned it because clearly my training had a hole in it.
Dale telling you to mark the roller housing with soapstone is basically the same trick I read about in an old tube rolling guide from the 70s. It said to set your roller depth first, mark it, then watch that mark like a hawk while you expand. The guide also said to stop when the tube just barely swells into the hole and you feel the torque jump, not when it sounds loud. Sound lies to you in a noisy shop because half the time you can't even hear the roller over everything else going on. Feel and that soapstone mark are what saved me on a heat exchanger job last year.