7500-ton forging press weld with 400 sub-welds

And it has to be done. You either have to do thermal stress relief or mechanical stress relief if the things get very large, because the residual stresses get to be huge. I told you the story about the big weld with 400 little welds in it — the big thing came off of a 7500-ton forging press. They didn't do proper preheat or post-heat, they didn't stress relieve, they didn't peen. Peening is when you hit it with a little hammer every half-inch of weld; you go in there and beat the surface to introduce mechanical stress relief by deforming the surface. Which is the way we used to put together battleships, 14-inch thick armor. No one remembers how to do it exactly, and no one wants to go out and build a battleship to prove how to do it. We don't really know how to weld 14-inch thick armored steels anymore, because all those people are dead.