Welding the big ring /

A group of men weld one area of a large ring in a fire. They lift the ring, which is hanging horizontally on chains, out of the fire. Four men hammer the hot area on the ring into shape while the remaining men hold the ring. They put the ring into the fire again, take it out, and take it over to a machine which continuously hammers down on that area of the ring. The men then take it away from the machine and hammer it themselves into shape. The ring is presumably a piece of a generator.