! one hour steaming, It is amazing what hot water will do for you.

Robby

For some more on direct-steaming systems, see US Patents 1,788,064 and 1.896.765.

That was an interesting read for someone like me with minimal knowledge of steam engine maintenance.

I have one question about the monthly boiler wash. According to the article, the procedure for cleaning the water sides of the boiler was as follows:

"The boiler is blown down through a 1-1/2" orifice to prevent too rapid cooling. ... The total time required for blowing and cooling the boiler down averages from 1-1/2 to 1-3/4 hour. ... The water is left in the boiler until the wash is about to begin to keep the scale soft. The boiler is washed with water at a pressure of 120 psi and at a temperature of 120 to 130 deg F."

My question is, how was the boiler washed with that 120 psi water used to remove the scale? Is this procedure similar to an automotive radiator flush?? I obviously have no knowledge of this aspect of steam loco maintenance.

(Edited to revise my question after thinking it over a bit.)

In part, this is the reason for the provision of 'washout plugs'. With these removed, a lance with a nozzle on the end can be inserted so the spray can be directed to reach specific areas of concern deep inside the boiler.

There also need to be provisions for the dislodged material to be removed from the boiler rather than just coming to settle in the mud ring or other low places, of course.

Part of some modern boiler treatments, the Porta-McMahon system for one, is to keep sludge 'mobile' in the boiler, so it never adheres as scale to any significant extent. These may still receive washouts, although they are now more required by Federal law than by necessity. I have seen a recent discussion on whether it is better to save and filter the removed boiler water, to save chemicals and reduce wastewater treatment, or just to refill and re-treat.

It is my opinion that holding pressure on the boiler, e.g. with dry nitrogen, as it is drained will reduce any tendency of the water to flash or 'cavitate' as it is transferred. That should permit boiler-water exchanges in minimum time, and with little or no pressure stress to the boiler. If the nitrogen is heated as it is introduced, it may assist in reducing thermal stress to the boiler structure as well, but that might require the introduction of some form of heater elements to keep the gas at full temperature, and some form of gas circulation past the elements if necessary.

bump

Part 2 here:

viewtopic.php?f=1&t=35330

This is a British film, but the techniques and practices aren't too far off from what was needed for steam anywhere:

http://www.youtube.com/watch?v=9fWnjd2eftY

Not as well detailed as the British film, but illustrating some American practices, is this New York Central film:

http://www.youtube.com/watch?v=NjxjLD00Pzc

Back to Great Britain and British locomotive maintenance:

http://www.youtube.com/watch?v=Z0bToe9DKFo

http://www.youtube.com/watch?v=HzybtS56l6A

http://www.youtube.com/watch?v=IxPRlhGqJ5o