@Dave NYC Hudson PRR K4 posted:Was the variation of days due to all the factors like age, how much work they did, or any other number of underlying factors, could you explain? I'm interested.
The variation in days between boiler washes was dictated by the poor quality of the water, i.e. the greater number of dissolved solids in the water, the more often the boilers needed to be washed. The UP, for example, had to wash boilers on locomotives assigned across Nebraska every 15 days account the massive quantities of dissolved minerals, etc., in the water.
EDIT/ADDED:
The main purpose of water treatment chemicals is to prevent the contaminants from adhering to the inside steel areas of the boiler, and thus causing "hot spots" from the baked-on minerals & mud. The worse the quality of the water, the more chemicals needed to be added, while the operating crews used the various blowdown & "sludge-remover" devices more and more often throughout their trip.
