Battleship gun barrel manufacturing facilities

Government-built early-20th-century heat-treatment facilities for long tubular forgings. Repurposed for generator rotors after WWII. Cited as the example of government-funded capability creating downstream commercial industry.

Why did those facilities exist? They existed because the U.S. government built them at the beginning of the 20th century to make battleship gun barrels, which are long tubular things that need to be heat-treated. No company would ever have invested in that type of manufacturing equipment based on generator rotor forging — it wasn't a big enough business. Once you had the facility, and someone else had paid for it, and they no longer needed battleship gun barrels, they found another use was to make generator rotor forgings. We never could have grown the electricity business that we have today if we hadn't started out building battleship gun barrels. Those facilities still exist, but we don't use them as much.