Overhead Steam Lines on Turntable "Garden" Tracks

[jimsabol]

In steam days, radial "garden" tracks off the turntable (not the ones that lead into the roundhouse) had overhead steam lines hung from poles with drops near each track.  How did these lines attach to the locomotive: through the steam pipes to the cylinders?  to the turret? through the steam dome?  What did the attaching fitting look like?  Were these used to bring dead locomotives to life (start up the blower, injector)?  Thanks for any info.  Jim Sabol

[marknewton]

The answer depends on which railroad you're asking about. In many locations I've observed , it wasn't just live steam piped to the garden tracks, but a combination of hot water and steam from a stationary boiler. Direct steaming usually employed a bolted connection to the blowdown/blowoff cocks. Steam would admitted to the boiler first to equalise the temperature, then water and steam together until the water was at or about a third of a glass, and pressure was about 10-15lbs. The water would then be shut off, and steam admitted until the required pressure is reached .

Also, common practice during the steam era was to carry out boiler washouts with hot water, and then immediately refill the boiler with more hot water to minimise damage due to quick expansion and contraction. As soon as the boiler was filled, the fire would be relit.

In addition to the blowdown cocks, most steam locos have a "filler"* plug, which may be located anywhere convenient above the normal water level - the backplate, or the front course of the boiler are typical locations. The filler hose would have an end fitting with the same thread as the washout plug, and simply screw into the whole. You could fill the loco through the dome, but the plug there is usually a much smaller diameter, used mainly for hydrostatic testing. Many European locos have a filler plug on the top of the barrel, with an attached funnel.

Likewise, a loco boiler being hydrostatically tested after repairs or inspection would be filled with hot water, again to minimise thermal stress.

I've seen many locos with a fitting in the blower line to allow the connection of external steam or air to run the blower during light-up - in my depot we used mainly air. I've also seen a number of places where there was an injector mounted on a convenient wall or post - these were used to supply washout water or fill boilers quickly, without requiring a pump.

*Australian terminology - US usage may differ!

[Anonymous]

Thank you for the explaination, I am constantly amazed at how much there is to learn about aspects of the hobby that are not usually covered. Your expertise is appreciated.

 

Will

[marknewton]

My pleasure Will, thanks for the compliment. It's interesting when you realise how many everyday aspects of steam operation are virtually unknown to modellers these days, bceause steam finished so early in the US. I'm fortunate that here in Australia, regular revenue steam operations lasted until 1988, and my own steam career ran from 1975 to 2003.

All the best,

Mark.

[jimsabol]

Thank you, Mark, for your thorough and clear explanation of the nature and use of overhead steam lines on the garden tracks of turntables.  I was the person who asked the question, but I see that a Mr.WOverdurff beat me to thanking you, but what's one more thanks when it's so richly deserved!  Interestingly, I've just been reading--in the paragraphs about James Watt--an explanation of what occurs "if a comparably small amount of steam (at the same temperature as boiling water . . . ) is bubbled through the cold water, it soon makes the water boil (we now know because the latent heat released as steam condenses to water)."  The Scientists, John and Mary Gribbin, Random House Inc., New York and Canada, 2002, page 253.  Jim Sabol.

[marknewton]

Again, Jim, my pleasure.

Funny you should mention James Watt. This Sunday I'm going to be spending a couple of hours running - very carefully - an engine he helped build.

http://www.powerhousemuseum.com/exhibitions/boulton&watt.asp

Needless to say, I'm rather excited at the prospect!

Cheers,

Mark.

[rrinker]

 That is simply amazing that an engine that old is still operable. I am constantly amazed at what was accomplished 2 and 300 years ago.

 

                                     --Randy

[rvanparys]

Mark:

Most of us who model steam have vague memories of our childhood... It is a pleasure to have someone with up to date knowledge...

 Thank you very much for your input and I hope to see more from you.

 Best regards,

Roger