I finally had a tube sheet crack on me during a hydro test
It happened last Thursday on a 500 psi boiler we were finishing up for a plant in Toledo. The crack was about four inches long, right along the weld seam on the lower left quadrant. We had to drain the whole thing, grind it out, and re-weld with a 7018 rod, which set us back a full day. The weird part was the pressure held fine until we hit 450 psi, then it just let go with a sharp ping. Has anyone else had a tube sheet fail like that during a test, and what do you think caused it?