I don’t believe the fireboxes of oil burners had floors. They sure didn’t need grates, or ashpans.
Old Timer
Wouldn’t they have to have something to form the bottom of the firebox?
I’m with you Murph, it doesn’t seem right to have the burners open to a major draft. Yes, you need combustion air, but you also want to transfer the heat to the water efficiently and not worry about the fire blowing out at running speed.
I would guess that it’s the damper, but you’ve seen it, I haven’t. On vertically drafted locomotives, like the one I work on, there is a square hole in the floor, which opens into a “box” of which one side is the damper door.
You’re absolutely right, I was keeping things simple. This teaches me to be mindful though that for every “fact” about steam locomotives, there are 17 railroads with different practices.
Dear Old Timer,
As Elliot pointed out, without a floor there would be an uncontrolled and massive amount of air coming in, and at high speeds the oil would quite easily be blown out.
The locomotive I volunteer on has a flat floor of steel which I assure you is quite thick. Other locomotives sometimes have a V-shaped floor with a flat bottom (SP 1795, for example).
Since it was brought up, here are some fineries of firing oil burners (random points):
1.) The fireman must increase the firing valve as the Amount Of Steam Used is increased (it’s not just the throttle–it’s the reverser). If the fireman doesn’t, the fire could be blown out because of a large draft (gives you a new appreciation of the exhaust nozzle that it could put out a locomotive’s fire). But, open it too much and you will be “forcing the fire,” which can cause leaky tubes and flues, and waste fuel. The engineer will tell the fireman when he plans to change the amount of steam used (like leaving the station). The firing quadrant (on which the firing lever is mounted) usually has a spot for an adjustable marker/stop for the “drifting fire”–the lowest amount of oil which can maintain full steam pressure when drifting. (The one I work on was converted to oil on the cheap in 1941, and doesn’t have a nice quadrant like that.)
2.) To keep the fireman entertained, he also has two other controls which require his constant attention–the atomizer and the damper. The atomizer valve controls how much steam is used at the burner.
Too little atomizer and the oil won’t atomize (what a surprise), too much and you’re wasting steam, and worse, making the fire burn cooler, and wasting oil. Either way leads to black smoke.
Too little damper and the oil won’t burn all the way–black smoke, wasted oil, colder fire. Too much damper and the fire can get too cold–black smoke, wasted oil (burning more to keep the same temperature); worst, too much damper and the flues will contract and leak.
Oh Murphy Siding!! Yes, the atomized oil burns in “mid air” and does not puddle in the bottom of the firebox. When I guest-engineered (drove) a small oil-fired Shary in 2002, I observed that the atomizer was in the back of the firebox, blowing forward. However, a current article on oil-fired Southern Pacific locomotives stated that was its practice then, but by 1905 it was changed to the opposite with the burner in the front of the firebox facing the rear.
Firstly, about the pressure gauge, I’ve never seen one on any locomotive (didn’t mean it didn’t happen though). The locomotive I volunteer on (Ventura County Railway no. 2) doesn’t have one, and neither does AT&SF 2926 to my knowledge. It really wouldn’t do you much good except in finding leaks (which is easy enough with the atomizer steam pipe).
Some had heating coils, but the old system of putting steam right into the oil worked pretty well. The oil pipe in the tender tank would rise up about 2", so that the heavier condensed water would fall below it, and only oil would be taken.
Not trying to be condescending, just helpful [:)].
Sincerely,
Daniel Parks
Cool! It kind of sounds like a tamed dragon.[:)]
Daniel,
I thought oil fired steam locomotives needed less sanding than coal fired locomotives ?
Some railroads put lights on the top of their locomotives so the fireman could see the smoke at night and adjust his fire.
? Can someone explain sanding the flues? For better traction of the smoke? I’m lost.
Thanks
Flues develop a build-up of soot on the inside, which decreases heat transfer and decreases gas flow through the flues. To clean the flues, the fireman threw a small scoop of sand into the firebox which would get sucked through the flues along with the hot gases, effectively sand blasting the inside of the flues. This usually resulted in a shower of soot coming out of the stack.
I suspect soot build-up depends in part on the fuel you’re burning. The NdeM burned a really heavy oil, and they had a lot of sooting of the flues. Their tenders had a rather large sand box right at the front of the tender, for easy access by the fireman.
Regards
Ed
Ed
A question was asked about Mexican 4-8-4s on this topic.
http://www.trains.com/community/forum/topic.asp?page=1&TOPIC_ID=44651
Would you have time to take a look ?
Chicken and egg question, of sorts: I’m reading that the oil had to be heated to 100 degrees in order to get it to flow. This heating was done using steam,presumably from the locomotive. It seems that you would need to have a fire burning, to make steam,to heat the oil,to feed the fire,to keep the fire burning ? How do you start one of these things?
Near the back of the September or October Trains in Selected Railroad Reading there should be a story of a Sunday afternoon watchman starting a fire by throwing buckets of diesel fuel into the firebox.
Practicality question: In reading about new fuel ideas including coal/water fuel and coal/oil blended fuel, the main problem is having to agitate the mixes to keep the coal fines from settling to the bottom of the tank. After reading through this thread, I see that there are also things that need to be done to make sure the bunker oil is of the right consistency for firing.
Is it really that much different in terms of added work to agitate coal/water and coal/oil mixtures as opposed to having to pre-heat bunker oil and steam-assist the spray?
Normal procedure where there was an engine house/round house would be to have a stationary boiler (often an old out of service boiler from a locomotive) fired up. This would usually provide steam for any machinery in the roundhouse as well as providing steam to keep steam locos (and their oil) warmed up while not in operation. Or have a hostler who’s job included keeping locos warm with low level fires. Cycling steam locomotives from cold start through operational temperature back to cold start is (as far as I have been told) harder on the equipment than maintaining it warm.
Regards
Ed
Oil-fired fireboxes had floors. I’m looking at two drawings of two different fireboxex arrangements. (One has the burner in the front, and the other in the back.) They both show floors that include air intake openings or dampers toward the forward end of the firebox.
Couldn’t imagine a floor-less firebox. When I operated an oil-fired Shay as a guest, I noticed a floor in the firebox. The burner on this one was in the rear, pointing forward.
Black smoke means too much fuel is being sprayed in relation to the draft, causing accelerated soot build-up in the flues, a waste of fue and offensive pollution. White smoke means insufficient oil for the amount of draft produced by the cylinder exhaust or blower. This causes cold air being drawn othrough the flues stressing the boiler. A grey haze is desired.
The fireman has to adjust the fuel oil/atomizer ratio for throttle changes made by the engineer. When the engine exhaust interval decreases, the fireman turns off the blower. The fireman has to watch out for the fire being blown out.
On sanding the flues:
1.) The cinders in coal acts like sand in cleaning the flues, thereby solving that problem.
2.) One little technicality: egmurphy called the scoop “small.” It really isn’t small, and I’ve heard of fireman tossing in a heck of a lot of sand to clean really dirty flues.
3.) When sanding the flues, you would usually close the dampers (to make a strong draft through the firebox door to carry the sand, which also makes the smoke turn black.
To elaborate a little on starting a cold boiler:
1.) Everything said so far is hunky-dory.
2.) In the cab of the locomotive is the firing manifold, from which the fireman controls the admission of steam to all of the oil-related steam usages, and the blower. There is usually a way to put steam into the manifold (frequently through the blower pipe).
3.) With a dead-cold boiler with no steam available (rare then, common now), diesel can be used, which doesn’t require heating, and compressed air can be used for the atomizer and blower. If you’ve got nothing, then build a wood fire, but be sure to clean it all out once you have steam going, since cinders could go out the stack (there isn’t as much cinder protection on an oil burner). You want to fire the boiler so that the pressure goes up at about 1-2 psi per minute, no more.
I hadn’t known about the smoke lights, cool!
I have heard of running with the blower on. It’s not the “correct” practice, but because of peculiarities of some locomotives, such as FEF-3’s, some fireman would do it.
Sincerely,
Daniel Parks
The blower nozel, located under the stack, was used to increase draft when the locomotive was stationary, moving slowly, or drifting, that is when the engine wasn’t working hard enough for the exhaust to create the necessary draft of air…
The less intense the fire, the more the dampers are closed to prevent the shock of cold air contacting the firebox walls or flues.