How particular were steam locomotives about the fuel they required? Could a locomotive burn any kind of coal or were certain types of coal required depending on the design of the locomotive fire box? For that matter could one make a Big Boy run on firewood?
This is a rather complicated subject, made even more complicated because some locomotives were convertible between fuels, and some were made to work on dual or multiple fuels.
Locomotives burning hard coal could usually be fired on bituminous (with a different technique and some additional care), but the opposite was not generally true. (See Angus Sinclair’s Development of the Locomotive Engine and the online references on the Wootten firebox that were posted a few days ago for more details)
Many engines built as oil burners were only set up to be fired on their ‘design fuel’ – usually #5 or #6 ‘bunker’ fuel oil. There are often problems firing a locomotive designed for this fuel on ‘lighter oil’ (particularly #2 diesel or home heating oil, and especially ‘winterized’ diesel or #1 that includes kerosene fractions)
A wide variety of potential conversions to oil were drawn up and, in some cases, parts fabricated during the mine strikes in the late '40s. I believe there are good drawings for both the J and A classes, the latter having a certain more-than-academic appeal…
The quality of bituminous coal could have a significant effect on locomotive performance, both in terms of heat release and ash characteristics. Too many variables for a short post. Same was true of coal quality – the AAR put on an extensive promotion in the late '40s and very early '50s for railroads to use washed 2" coal with few ‘mine run’ adulterants. One of the great advantages of ‘late’ wide-firebox designs with FireBar grates was that a wide variety of relatively poor coals could be cost-effectively burned and good steaming maintained (without the fireman either being a one-armed paperhanger or a refugee from a minstrel show).
There are a couple of problems with firewood as a locomotive fuel, especially the ‘good’ kind (like fatwood). It ignites readily when properly seasoned, bu
The locomotive firebox was designed to burn the particular coal available to the railroad. Like anything else you get optimum performance when everything is designed to work together. Anthracite and bituminous coals burn very differently. They require a different type of fire. A Lackawanna locomotive burning anthracite had a very different firebox from a bituminous burning locomotive. A steam locomotive can burn anything that provides sufficient heat to boil water. Of course, wood does not generate the heat that coal or oil provide.
Wood worked well in locomotives that were designed for it, like those cool 19th Century steamers we all know and love so well, or at least that I do.
Wood did have some advantages, being easily ignited and burning clean with little ash remaining to dispose of. Disadvantages, not as many BTU’s as coal or oil, and sparks, lots of 'em, which lead to those “balloon” smokestacks.
Matter of fact, the Tavares, Eustis and Gulf Railroad in Florida runs their 2-6-0 on wood fuel, which makes sense. There’s no coal in Florida, and there’s plenty of scrap lumber available which is cheaper than using oil.
Interesting Overmod’s comment about oil burners only working well with bunker oils. When Canadian Pacific had a steam program with Hudson 2816 they switched from bunker oil to waste oil in 2002, bunker oil being hard to find anywhere on the system except for the Pacific Coast. Then one day in 2003 the fuel truck didn’t show up so they filled it with diesel fuel. They had no problems and never looked back. Bill Stetler, then in charge of the program said “The engine doesn’t care what it’s burning. We were worried about the viscosity but the BTU’s are there.” Of course, CP doesn’t have a steam program (at the moment) so it’s all a moot point anyway.
Not trying to start an argument but I thought I’d bring that up.
Somewhat off-topic:
My dad once rode an excursion around the 1970’s on the E-L in Ohio behind a RDG T-1. I think it was 2102. They were burning some very bad coal, which was quickly depleted. They actually picked up some pieces of discarded ties and tried to burn those, but it was futile and the engine and train had to be towed in.
My dad had been in the coal business many years before. He did a “railfan inspection” of the engine before departure, and expressed his misgivings about the coal. The people he talked to dismissed him as a foolish old man. They seemed to think “Coal is coal”. My dad would say “bad coal is dirt; good coal is fuel”.
Tom
Note that this is the reason I have qualifying words like “some” and “often” in there.
The design of the burner and nozzle, the steam or mechanical pressure used, the arrangement for primary and secondary air, and the skill and knowledge of the fireman and engineer are all part of the situation. Note that the Frisco 1522 crew also reported that it easily made the transition from heavy to light oil firing with little difficulty. But there are plenty of disastrous attempts at implementing light oil firing in situations where a simple von Boden-Ingles burner (either forward or rear-firing) would produce a fine luminous plume using little more than properly-adjusted steam. And there are also no few conversions where ‘wisdom’ in the ways of industrial #2 oil firing have NOT translated well to locomotives, Reading 2100 being an interesting case in point (which was partially, but not completely, re-engineered but never quite ‘fixed’).
I think the general consensus concerning the previous owners of Reading 2100 and their abortive oil-firing conversion is they’d bitten off more than they could chew and really didn’t know what the hell they’d gotten themselves into.
'Nuff said there, hopefully the locomotive’s in much more capable hands now.
This discussion of oil firing reminds me of something. I’ve seen some excursion footage of Burlington 5632 in the early '60s. There’s some shots of the locomotive belching out a heavy black smokescreen, thick enough to turn a World War Two “Fletcher” class destroyer green with envy! “Well,” I said to myself, “there could be several things going on here. Either the head-end crew’s hamming it up for the run-by cameras, OR they’ve got an incredibly bad load of fuel oil, OR that engine’s in dire need of servicing, OR the fireboy’s got no idea of what he’s doing!”
Or maybe all four?
I cannot speak for all of 5632’s excursions, but when I rode behind it mostly in an open gondola, Union Station to White Pines and return, I was grimy, but not too bad. The only time I saw it pouring out dense sooty smoke was for reason #1 (“the head-end crew’s hamming it up for the run-by cameras”) on that excursion and three other times I was a bystander.
The usual reasons are (1) as stated, ‘richening’ the feed to ‘give the fans what they want’ (insert comparisons with contemporary diesel-driving children ‘rolling coal’); and (2) periodically sanding the flues to clear them of accumulated soot.
When burning heavy oil, not all the fuel combusts, and a combination of liquid gunk and solid carbon particulates adheres to metal surfaces. Preferentially this occurs with gas speed and vector changes, especially at the rear tubeplate, and where active combustion in the gas plume ceases (almost immediately after entering the tubes). This has to be cleaned out fairly regularly or it will build up, inpede both the draft and distribution through the tubes, etc.
It is not practical to do this with steam or air 'soot blowers&
Atho’ not an Expert firing with Oil, I do know that Railfans like SMOKE, and, to this end they can be accomidated by overfeeding oil to the Firebox.
More Oil = More Smoke.
BUT, there is a downside.
More Smoke = More Soot on surfaces of Tubes, Flues and Superheaters lessening heat conduction to water/steam inside.
Sand is used, under heavy draft with throttle and Johnson bar to clean same, as required = Sanding Out.
Another risk is that too much oil will crowd the fire until it turns dark red from lack of 02 and will PUFF out flames from fire door sand hole and draft as starving for air.
I have never had the fire go out from over-Firing, but, it can and will go out of it’s own accord from water in oil, or high wind.
Just when you think nothing can go wrong, it will.
( One day we derailed the lead truck on the first car as brake rigging btwn axles came down, dug in, and Jill Poked car off track. We were all there fooling around with replacers and spike mauls and wedges from top of Tender Tank and safeties lifted as fire a bit too high.
The Engineer, who was in a bad mood and hated being off ‘His’ seat, said ‘F It, let them blow!’ I reminded him the safeties were on there to release generated steam in EXCESS to that able to be produced by fire and boiler, and would draw the water down as fast as working Engine at full power = dry Crown Sheet, eventually.
He implied I was retarded, and it was the Fireman’s ( Me ) job to look after the Fire and the Water.
Safety First? )
When the Fire goes out, the Fireman by judging the smoke from the stack, or darkness when there should be orange thru sand hole, yells Fire Out!! The Engineer slams the throttle to cut the draft.
Fireman shuts off oil and atomizer, opens Blower a tad.
If there is oil pooling in the hot Firebox, fire OUT, bricks and
Or, Why only an Idiot Puts the Superheater on the Far Side of the Regulator.
Even if you can jam the regulator closed again, on a Black Five doing this, you’ll be Blue Petering until (1) all the excess new steam has blown through, or (2) somebody grabs the unwinding reverser handle and cranks it back a good way toward mid. At least the screw reverser handle didn’t clock the poor guy on the jaw this time on its way out…
Yikes, some film clip! Goes to show not everybody gets it right all the time, not even the Brits. Oh well, mistakes are there to be learned from.
Only the winners of NASCAR races should be doing “burnouts.”
Great Data.
Thank You.
The actual answers are at a bit of a right angle to what you are probably expecting.
A principal reason for implementing a multiple is that instead of throttling a large port, the multiple cammed open a number of ports progressively, each one having relatively good flow. There was also one relatively small port that cracked open ‘first’ to avoid the problem seen on the British engine, the pressure differential tending to hold the throttle open with unexpected force.
However, as early as 1912 the Germans had a positive and very effective ‘dome’ answer to most of the issues objectively involved with a dome throttle’s steam flow characteristics: the Wagner throttle. This was an early (and quite effective) version of a fluidic amplifier, which used a small shaped plug and passage to control differential pressure across a much larger throttle valve ‘in servo’.
The next issue that a large dry pipe and restricted vertical clearance poses is that of water separation at or near the throttle. The multiple ‘cheats’ at this because it puts the whole length of the dry pipe up to the header and then the whole length of the elements ahead of the throttle’s ports, so any water carryover has a better chance of evaporating and then becoming reasonably superheated by the time it would be passing the throttle with sufficient liquid mass to give runaway issues. But it would not be ‘impossibly’ difficult to use a Wagner throttle there, perhaps acting in much the same way as a conventional dome throttle but well
Thank You for the valuable info!
Had the Diesels not come, it would be interesting to see how ‘Steam’ would have evolved.
Had not the War not intervened, Mr. D’s Machine may well have accomplished it’s task much sooner.
QED?
Take Care.
Our fathers should have met or maybe they did in a better place. Mine spent 35 years as an engineer on steam and later, of course, Diesel tow boats pushing coal from WV mines to Pittsburgh steel mills. His opinion of coal was about like your dad’s. By the time I was 10, I knew better than to call lignite coal. I might get away with calling it soft coal but that was as far as I dared go.
And he was just as picky about what went into our furnace at home. I was expected to set the slate aside in the coal bin under the front porch. It had better not show up blocking the grates!
On a somewhat related note, he got disgusted when someone talked about an “automatic” stoker. He always insisted there was no such thing. Powered, yes; automatic, no.