Does anyone know what the PSI rating was for those boilers?
I ask because I served on a Adams class Destroyer (DDG-22) and they were reputed to be the last of the 1200 PSI steam plants in the US Navy.
Invisible steam that could cut you in half if you walked by a leak.
horsepower and cylinder sizes were computed based on 300 psi boiler
https://store.steampowered.com/manual/208361
The Big Boy operated at 250 PSI. The boiler had a decent safety margin. I spent a lot of time looking one of these over at the museum near Saint Louis. That is one very large machine! The pistons are 24” in diameter.