European freight yard operations vs US Operations

On 8/29/2009 5:07 PM Roger T. spake thus:
Wow. How quintessentially ... British, which is to say insular. Little cars trundling around a little island ...
Reply to
David Nebenzahl
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I'll try and find some photos. But I've seen rakes of wagons with standard couplings on the outside and semi-permanent drawbar connection inside. Could have been wagons for ISO containers. It's been a while since I went back to the UK.
Reply to
Christopher A. Lee
"Christopher A. Lee
These are articulated freight cars and we have them in North America. It's not the "train" running in fixed rakes but articulated freight cars within the train. Like these
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. Not quite the same thing as an "fixed rake" freight train. Trains that run in (generally) fixed rakes are known as "unit trains" in North America or in the UK, "merry-go-round" or "mgr" trains and these will be made up of similar but individual cars that remain coupled together and run from source, usually a coal mine, to a customer, say a generating plant or perhaps a lake head or sea port. Try Google for "unit train", "merry-go-round train" or "mgr" train for a fuller explanation.
Reply to
Roger T.
No. They're not articulated - each has two bogie trucks. It's a rake of several wagons with a standard coupling on the outside to couple with an engine of a similar rake. Between the bagons is a different kind of simpler coupling more like a drawbar that is not designed to be separated in service. I've never heard them called articulated before, they're separate wagons with standard couplers on the outside of the rakes,
Reply to
Christopher A. Lee
Now I understand. I think they made some hoppers like that in North America and perhaps some intermodal cars. Two cars, with drawbar and carrying one number.
Reply to
Roger T.
[...]
I lived in England off and on 1945-54, in Stratford-upon-Avon my mother's hometown), about 1/2 a block from the GWR. Most freight trains were "unfitted." You could here the slack running in and out from a mile away, if the wind was right.
These trains were short (30 wagons was a "long" train", and travelled slo-o-o-owly - about 15-20mph by my (hindsighted) estimate.
cheers, wolf k.
Reply to
Wolf K
And many unit coal trains have cars fitted with special couplers (so they can be rotated) or bottom hatches (so that they don't need manual opening) in order to unload them without uncoupling, or without stopping.... Now that's an operation I'd like to see done in HO. ;-)
wolf k.
Reply to
Wolf K
Local HO club has it.
Starts with a working coal loding facility all the way around the layout to a working rotary dump facility.
Cars have custom modified rotary couplers on them.
Reply to
Alan Larsson
I think they also did it with shorty tank cars.
This included connecting the tanks so they could act as one large tank for filling or draining.
Reply to
Alan Larsson
Umm, not really! Many freight trains, but more especially coal, were often built up through accessing many short branch lines, collecting from, and delivering to, other short branch lines, throughout industrial districts or coal mining districts, with difficult access. They were often very short runs.
The merry-go-round coal trains for power stations came very much later with longer runs, collecting from fewer and much larger coal pits. (I worked on some of the coal handling plants which received these trains) The system was and is very efficient.
If I may take the opportunity and go slightly OT, I have never been able to understand US practice with coal drags, where as many as 100 wagons (?) were coupled (10,000 tons ?) being typical but frequently ran at well below locomotive economic running speed, walking speed no less, and, I understand, often stalled. How come? This has puzzled me for a long time.
I have several CD's of C&O showing Allegheny H8's just crawling with mile long coal drags!
Any explanations, please.
I mean, one could equally ask, why choose the Mallet system as opposed to the Beyer Garratt?
Reply to
Brian Bailey
[...]
Ore trains in the Missabe Range were in that range, too. That's the reason for the Yellowstone, a 2-8-8-4 that had greater weight on drivers and greater tractive effort than the Bog Boy (which was heavier overall.)
Here are some of the things I've figured out from my reading, and from recall of the thermodynamics course I took many years ago. I don't claim it's a complete explanation, but it's certainly part of it.
Those locos were designed as "drag" locos, for low speed and heavy trains. The economics of steam locomotive speeds are complicated. The drag locos were designed to be most economical at low speeds, in the 15-20mph range. Articulation was used because you essentially get two engines for the price of 1-1/2, with a single crew. And as with all engines, bigger means more efficient.
Mallet vs Beyer-Garratt is a "cultural" difference, heavily influenced by NIH syndrome. Also, IIRC, Beyer-Garratt was patented, while the Mallet was just a compound articulated loco, anybody could build one without paying royalties. A lot of so-called Mallets were simple engines, though.
There are other aspects to the economics of trains. The sheer amount of coal to be hauled is one. The logistics of managing many short, lighter, faster trains are complex compared to fewer, longer, heavier, slower ones, and it's worse when they run on the same tracks. Railroads hate mixing freight and passenger trains for this reason. It requires extra tracks and passing sidings, more complex signalling, and so on.
By the time all these and other factors are balanced against each other, running a heavy trains at less than the engine's most economical speed was a minor cost compared to others.
I'm sure there are many things I've overlooked.
HTH wolf k.
Reply to
Wolf K
Yes, they were big weren't they. As I understand it the Big Boy wasn't especially efficient, or wasn't run efficiently, and threw a lot of coal, unburnt, up the stack. The fuel was just so cheap that it didn't matter.
Sometimes, it depends how you run them.
I'm sure your right!
True! That must have influenced decision making.
The early one's, yes.
I think that 'all' the later ones were, weren't they?
That's certainly true in the UK.
But, weren't many US long haul tracks virtually dedicated solely to coal and/or ore, though?
ie. fuel was cheap at the time. But, as an admirer of the engineering of both the Yellowstones and the Lima H8's, I am aware that the economical running speed of both was far higher than what was current running practice. I mean, CD's showing Yellowstones on the Doluth Missabe and Iron Range show them to be really shifting, whereas the H8's were capable of far higher speeds than was normal practice which appeared to be slow coal drags. I think that I am correct in thinking that C&O didn't really know the H8's full capabilities until it was far too late to utilise it.
No worries, me too.
Brian
Reply to
Brian Bailey
Not all - the last of Norfolk & Western's Y6bs was built in 1952, and they were compound to the end. It is said that the next N&W drag loco (the Y7) would have been a simple, however.
Tim
Reply to
Tim Illingworth

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