Quonset Point submarine hull cap fixturing and welding practice

Student-led description of automated tractor-welding of pre-triangulated submarine cap heads, ~100 weld passes per joint, back-gouging, inert gas shielding, 3mm defect limit. Tom then adds the secrecy aside about Soviet satellite measurement of hull thickness.

Student: Even though welding by hand causes a lot of imperfections, the boys' ones — like this they push the heavy heads of a submarine, and can you tell us how thick it is? I was surprised. This is technical. They have a frame stand especially for the caps, and now they pre-triangulate them together and make them in a perfect angle so they don't have gaps. And what they do is they run a barrel track across the seam, and they put an automated mechanized welding machine, and they have a geyser strain walk along with it. So they just relax it, and it walks back and forth across the welding every time. And the welds consistently lay down — there's some hundred passes that go into this. And then of course they flip it upside down, gouge out the back of the weld, just to make sure there's a clean surface to weld through. And they're flooding it with inert gas to make sure the accumulation of inert gases passes out down there. And then they do this exact same thing for the reverse side. And of course they buff it out, and then it rolls down the line, and you can't have a defect bigger than three millimeters in there. They crank them out, they're always working on one way or the other.