Generator rotor shaft welding feasibility study (US Steel)

As a young engineer at Bethlehem Steel (~1975), Tom was asked whether two ~40-inch-diameter forgings could be welded together to make the 750,000-pound (375-ton) generator rotor shafts required for 1,000 MW power plants. Only Bethlehem Steel, US Steel, Creusot-Loire in France, and one Japanese forging house (Tom guesses "Tokyo Steel" but is uncertain — historically Japan Steel Works) had the ingot/forging/heat-treatment capacity, originally installed ~1910–1915 for battleship gun barrels. Forging takes more than a year per shaft. Electroslag or narrow-gap welding could in principle have done it; no one funded the trial.

First of all, you're not going to see them on little shafts. You're going to see them on really big shafts. And if you think about it, we don't do as many really big shafts as we used to. The forging shops that do these things don't exist like they used to. That was actually one of the projects I had when I was at the steel mill. They asked me if we could weld together two forty-inch-diameter cylinders — basically two ingots or two forgings. The reason was: the world's largest single part made out of metal is a 750,000-pound — so 375-ton — generator rotor shaft, and this is for like a 1,000-megawatt electric generator. So this is a General Electric or Siemens-Westinghouse. These are the largest electrical generators made in the world. Outside of maybe the Soviet Union — I'm sure they could do this if they could make decent quality steel — there's one facility, Creusot-Loire in France. There may be one facility in Japan, maybe Tokyo Steel. I can't remember the name of the big steel company that does the big forgings in Japan.