I’ve been wondering if soot, cinders and sand accumulated in the bottom of smokeboxes? Was it necessary for employees to go in there from time to time to shovel it out?
Short answer - yes, and yes. That’s why smokebox doors are relatively easy to unfasten (dogged shut, rather than bolted.)
Some locomotives were built with hopper arrangements in the bottom of the smokebox, which could be (mostly) emptied without opening the main smokebox door. There were other arrangements for dealing with ash, including the screened stacks and ducting that the Colorado and Southern applied to narrow gauge locomotives. For a time, the Kiso Forest Railway equipped their woodburners with ash collector bins at the bases of their cyclone stacks. They rode on the upper curves of the smokebox like saddlebags, and caused the locomotives to look like gerbils.
Chuck
The smokebox is at atmospheric pressure so there is no need to hold the door shut with anything but a few bolts. Soot and sand (used to clean the flues) build up in the bottom of the smokebox and it can easily be shoveled out. The smokebox usually includes deflectors that attempt to keep in large chunks and keep down the sparks from the stack. Coal doesn’t leave much soot but wood certainly can. Also note that the smokebox shell can be much hotter than the boiler and thus is painted with linseed oil and graphite.
Thanks guys. Thank must have been a hot dirty job.
When the local motel sees steam engine crews show up for a room, they give us a special (already gray) set of towels. They understand that we will try to get clean and don’t want to ruin a good set of towels. I can’t imagine how roundhouse crews ever got clean after a day of work.
Actually, the smokebox should be under a partial vacuum – this is the result of the ejector (smokestack) nozzle pulling gas out of the smokebox, which in turn pulls hot combustion gases through the flues to boil the water and apply superheat to the tube elements.
You need some kind of seal on the smokebox door to maintain that suction through the flues providing the draft. Yeah, if it leaks a little I suppose that is OK, but it cannot be a straight atmospheric pressure.
This is my understanding. The reason the exhaust steam from the cylinders and the blower are all directed up the petticoat pipe is precisely to generate a strong vacuum behind them. As they eject steam up the pipe and out the stack, they induce a draw from all the flues, and this draw causes more air to enter the combustion chamber (firebox), which is desirable. In the icase of the blower, this appliance assists a stationary steam locomotive to maintain adequate combustion and heat moving down the flues to keep the boiler hot. Fires would often go out if a fireman forgot to turn up the blower when the engine stopped for any length of time. For steamers working hard, and therefore using lots of steam, the chuffing engine was directing all it’s expanded steam up the stack and causing a massive pulsing draw through the tubes. This kept the fire burning hot and constantly, in turn maintaining a sufficient amount of steam pressure.
In the case of coal burners, if the engine spun its drivers, the resultant mad draw of air through the flues caused by the sudden blast of steam up the stack would often tear large holes in the coal bed in the firebox. That would allow a column of cold air to rush directly up through the grate, into the tubes, and the cooling effect on the inlet to the tubes at the firebox would result in broken seals. Steam might leak into the firebox and blow back the fire into the cab. Not cool…at all.
-Crandell
Most of the larger steam era roundhouses had a well equipped wqshroom available for p;ersonnel going off duty. One feature was a massive round concrete sink that several men could use at the same time plus lockers and other facilities. I saw one of these in the old Reading Co. roundhouse in Wilmington DE just before it was torn down and even found an employee timetable dating from 1947 in one of the lockers.
Around 1970 I had the good fortune to take a cab ride aboard “Puffing Billy”, a narrow gauge line near Melbourne, Australia. The line was worked by 2-6-2T engines pulling open air excursion cars. These locomotives were very small. Mounted on the pilot, directly below the smokebox door, was a sheet metal chute allowing the crew to shovel out the smokebox at the end of every run. The runs weren’t very long, perhaps ten miles or so, but by the end of it the smokebox would be half full of ash and small cinders combined with bits of unburned coal. This was by no means the entire amount of cinders produced by the fire. A good share did go up the stack and most of the riders had cinders in their hair, stuck to their teeth (yes, they were all smiling) and in their clothes.
I do not think such chutes were at all common on North American steam, and I didn’t see them on other Victorian Railways steam classes (if I remember correctly). Nevertheless, disposing of cinders, when necessary, is always a chore.
One of the reasons these small engines produced such copious quantities of cinders was that the grades were quite steep and a fully loaded train taxed the capacity of the locomotive beyond its normal rating. The boiler was surely overloaded, producing copious quantities of black smoke and partially burned fuel. If the boiler had not worked so hard (as on the return, downhill trip), the gases at the top of the stack would hardly look like dark smoke, but instead like white steam with perhaps a tinge of gray mixed in. With running like this, cinders would not accumulate in the smokebox nearly as fast, and the engine could go a long way before requiring the smokebox to be cleaned.
Crandell you are 100% correct no one could have explained it better.
Regarding cleaning smoke boxes, in the Victorian Railways nearly all the steam locomotives had self cleaning smoke boxes, you never had to shovel them out. On those locos not so fitted cleaning the smoke box was a very dirty job.
Back in the '90s there was a very fine magazine called “Locomotive and Railway Preservation”, wish it was still around! Anyway, one issue had an article on graphiting smokeboxes. The reason for this was, as the author said, that for most of the steam era the paints available just wouldn’t stick to the smokebox steel for very long, the heat would blister them off in no time. Remember, the smokebox area wasn’t insulated like the rest of the boiler. When better heat resistant paints became available the steam era was nearly over.