cylinders

OK folks, please don't laugh but a simple question. How does steam reach the cylinders?

Warm air rises, so how does opening the regulator force steam down into the cylinders. Then after working the pistons, instead of going all the way to the chimney, would it not be practical to have an exhaust vent on the cylinders instead?

Ive read through the "Handbook for Railway steam locomotive enginemen" but it's still not clear.

 

Oh dear ](*,)


Well, 22A, simply put, gas under pressure will move towards somewhere with less pressure, so the steam under high pressure in the boiler will move into the relatively low pressure steam pipe. When the 'fresh' steam puts pressure on one side of the piston, the 'old' steam on the other side is forced, under pressure, up the exhaust, the exhaust going out through the smokebox also helps to create a pulling effect on the gases in the the tubes and firebox, which means that more air is heated in the firebox and dragged through the tubes, which heats more of the water in the boiler, helping to make more steam. The air enters the firebox through the ashpan doors and firehole door, so that a vacuum isn't created in the firebox.

I hope that helps answer your question.

 

Thank you.