It is my understanding that it takes awhile to get a steam egine up and running., In the sense, you just dont go out and turn the switch on and hit the gas…
So…
Take a regualr mainline steam engine that would be used in regular service Such as SP Cab Forward, ATSF 4-8-4, or even a Big Boy for that matter… if it works the day run and comes back home for the night and tie it up, they leave it running? (pardon the lack of proper words, I have no idea) Such as a diesel is easier to let idle then shut it down every day. So, if that is case, and I would assume a steam engine is harder to shut down and start up a then a diesel engine, how long would those things stay warm? Would they stay lit until they were serviced? How long would that be? 7 days? 30 days?
Thanks guys
Just a curiosty question, trying to figure out the ways of the “old days”
The proceedure w/ a steam engine would be to wahe running gear, replenihe fuel and water in the tender (although that might also be done as the engine was being readied for an outbound run), and then dump the fire. In the case of a coal burning engine the fire and attendant ashes and cinders would be dropped into a pit under the tracks, in the case of an oil burner the fuel would be cut off. The engine would then pull into the roundhouse (running on residual steam pressure) where it’s running gear and boiler would be inspected and it would be lubricated for its next run. One of the many really nasty jobs on the RR was climbing into the firebox and smokebox of the still hot engine to check for steam leaks in the flues. If the engine was to go out relatively soon it might be hooked up to a roundhouse steam supply to be kept hot or a light fire kept going by the hostler to keep up some steam pressure.
If the engine had been allowed to cool down it would be necessary to start a fresh fire and build up a fresh head of steam. The roundhouse steam connection might be used to activate the blower until sufficient pressure had been built up for the engine to power its blower on its own.
All of the rigamaroll attendant to maintaining steam engines was a major factor in the replacement of steam w/ diesels.
At Steamtown our locomotives are kept hot for up to 30 days, the boiler wash interval. At the end of the day, we do the fire and ash pan cleaning like Jim mentioned above, but the fire is banked. A thin layer of coal is laid on the front half of the grate and a thick pile of coal is laid on the back half. This is allowed to coke overnight. The boiler is also “bottled up.” The injector is run until it just won’t put any more water in the boiler, usually above the water glass height. By next morning, we still have 75 to 100 PSI on the gauge and enough of a smoldering coal pile to relight easily.
Was it Trains or Classic Trains that recently had the somewhat humorous account of warming up cold steamer?
Considering the considerable mass of water that had to be brought up to steam (as well as the potential for damage to the metal if it’s heated up too quickly), it’s not going to be a quick job. Hence keeping a fire going and/or staying on house steam.
Cold Start of a steam engine would require at least 24 hours to get a large steam engine up to operating conditions. The 75 to 100 psi pressure TomDiehl mentioned translates to minimum steam temperature of about 320 degrees Farenheit. The problem with heating a metal steam system up too quickly is that large temperature differences within a steam plant result in different expansion rates within the structure. This is what causes the damage to the sheet metal. This issue apllies to steam power plants as well as locomotives. It may take a week to bring up a Megawatt power plant to full capacity from a cold start.
At Golden Spike NHS, we take 2 days to bring the engines to operating temperature from dead cold. The first day is a light fire to bring all that metal in the firebox, boiler, etc up to a uniform temperature - hot but no pressure. Then it is left overnight to equalize. There is a lot of metal that needs to expand.
The second day then takes two - three hours to bring the boiler up at about 120 to 140 psi. That is about 350 degrees.
When in operation, we leave the boiler filled just about to the top of the water glass and bank the fire at night and it generally goes out - but leaves us with about 10 to 15 psi in the morning. Some kindling and the fire quckly relights. The low pressure is sufficient to run the blowers when the fire is ready. We also use electric extractor fans to reduce the amount of smoke in the engine house – they augment the draft a little.
Takes about 2 hours to get up to operation each morning. By that time, we have lubed everything, checked all the valves, and refilled the tender with water. After getting operational, we pull the engines out of the engine house for refueling (coal in 119, wood for the Jupiter), then a final walkaround and they are ready (and eager) to go.
I had read that link previously, and have no reason to doubt the claims it makes. The timeline this fellow talks about, stone cold to running order, is a mere 7 hours, give or take, and I believe his loco was a light Mike, but not sure.
It would seem to me that a large steamer, like a Berk or a Northern, and for sure the larger articulated ones, would take close to 14 hours to get operational, but two days seems to be long. I am not a pro, nor especially “enlightened” on things steam, but there is quite a disparity, at face value, between claims of 2 days vice 12-15 hours.
When you’re talking about rare or historic steam locomotives, the two day figure is probably correct for most operations. As someone stated above, they want to equalize the expansion and the slow warmup is just working on the cautious side.
Thank-you, Tom, and for your reply elsewhere. So, would it be correct, in context, to say that in 1946, bringing a Big Boy up to moving order from two weeks in the backshop(stone cold) would be around 10 hours, depending on company policies/practices?
I’ve worked mainly with Pacifics and Mikados, never dealt with anything the size of a Big Boy. I don’t know if the boiler size would cause any more warmup time or not. The one at Steamtown most likely will never run again. Maybe if someone here had some experience with the Challenger this might give us an idea.
Yes we could do it fster than two days - but no one works the night shifts - so two days is just about right. And yes - we do error on the side of caution. For example, our safety valves are set at 155 pounds even though the boiler is rated for much more.
Thanks for the opportunity to read Phil Jern’s beautiful description of the beautiful job he does every third day. I hope it will be reprinted in TRAINS or CLASSIC TRAINS.