Question on British Steam

[sawyer811]

Okay, please nobody jump me, but i have a question on british steam engines and their operation. Recently, while trolling rrpictures.net i found this picture...

the caption says this is a water stop and it said this is all ash (i assume) from the firebox. i guess i have two questions: 1) how is this possible?! If this is a water stop, then the engine has to be under steam, right? why would you kill it just to take on water? yet every steam video fromb britian seems to show the engine "dead" when it stops at the water crane. no steam, no smoke, no anything. maybe i'm too used to how we operate steam here in america, but to open the front of an engine up like this would destroy the vacuum that the fire needs to burn...right?

the second question is this, how on earth is all this getting in the smokebox?!? i'm no expert on british steam and their operations, and will never claim to be, but i've ridden behind enough coal-fired steam engines here in the states and here, the ash either ends up in the ashpan or completey exhausted up the smokestack. I'm stumped to this. does all this have to do with the grade of coal they burn?

I hope this didn't come off as snotty or arrogant or anything someone might take as offensive. I'm just a yank, and i can only go off what i've seen from steam operations here, but i know they're very different from operations in Britain. But to a american steam enthusiast like me, this doesn't make sense. could someone explain this for me?

 

[BLACKWATCH]

As far as I know, when a loco is watering, to preserve the fire, it is "damped down" & the firebox doors are closed, hence no smoke or steam (unless bad coal is being used).

The ash in the smokebox gets there because, when a loco is working hard, the draught created by the blastpipe under the chimney, is sufficient to draw the lighter burning material through the boiler tubes into the smokebox, where it either goes up & out of the chimney, or just accumulates as seen it the picture.

 

[stovepipe]

Interesting picture....

It should be ash in the smokebox, but this looks more like part-burnt coal to me......which would indicate the combustion wasn't taking place properly. It could be poor quality of coal, driving, or firing, - perhaps a combination of all three.

 

[sawyer811]

okay, follow-up question then...what exactly does it mean when you say "damped down and the firebox doors closed" does that mean the firedoors at the back of the firebox are closed, or is there another one at the front? agian, my lack of knowledge of british steam comes into play here. this may be an utterly stupid question, but you can never tell with british engine designs

I mean that in a good way BTW.

PS, i think that engine needs some to blow its nose she looks a little stuffed up.

 

[stovepipe]

Well... dampers are the air vents below the firegrate, which can be closed or partially closed to reduce the air flow which slows down the rate of combustion in the firebox.

Useful for improving coal consumption and helping to stop the boiler blowing off when stationary, and also when running downgrade. I'm sure US locos must have dampers though, or at least some means of controlling the primary air for combustion?

British locos were almost all handfired - through the firebox doors, which were closed when firing was not taking place, or when going through tunnels, to prevent blowback.

 

[sawyer811]

I know that most engines here were auto-fired with a stoker, and usually only hand-fired when they were hostled, or when working hard up a hill. yes, you did have to hand-shovel the back corners of the firebox, but that was usually it. dampers are a european thing, i think. i think the closest we came was the shaker bars that cleaned the fire. for the most part we just let the fire burn. The fires here usually breathed through the ashpan, and there's usually a slit between that and the firebox itself. remember, here we had to deal with massive fireboxes with up to 100sqr. ft of fire grate or more. that required a lot of air to keep running. I've been all over the steam engine near my home with its labeled controls. there's no damper in her cab that i can see.

 

[IsambardKingdomBrunel]

Obviously a modern day pic of an ex-GWR loco running on inferior quality coal.

Those locos were designed to run on high quality welsh steam coal.

Not some cheap and nasty crap imported from abroad.

IKB.

 

[sawyer811]

should have seen that coming...looks like it needs a 9F to come to its rescue.

*Castle class* hack hack hack cough wheeze cough my god, what do they have me burning, blackened sawdust?

*fireman looks in tender* umm, yes

*Double-chimney 9F* snicker

*Castle Punches 9F*