I asked a question a while back that probably was too narrow to get a detailed answer. Basically the US and European coupler systems are different. This has to lead to a difference in how yard operations, in assembling a freight train are performed. If I remember right from books I read many years ago in some US yards a box car could be pushed onto a slooped section and allowed to coast and automatically couple to the end of a freight. With the European coupler I would exoect you would "gently" move the new car to the end of the freight - perform the hookup and then back off the yard switcher engine. Where can I get details of this.
Yes, but not particularly gently. The buffers would be compressed so the chain had enough slack to hook it up.
Britain and (I think) the rest of Europe had what they called "hump" marshalling yards which sound a bit like the sloped section you talk about - the wagons were pushed over a small hill and then freewheeled through a fan of turnouts onto the right track. There were retarders to slow the wagons down to the right speed.The only real difference was that coupling up was done manually.
1) The don't use a "chain" in Europe, it's "coupler", in Europe usually a "screw coupler" and in the UK they used three types. The "three link", the "instanter" and the "screw" coupler.
2) Europe and the UK are two different entities. I can only speak for the UK.
The three link coupler was only used on freight cars that had no automatic brake. The three link coupler leaves a gap between the buffers and thus an unfitted (Unbraked) freight has a fair bit of slack.
The instanter coupler was used on fitted (braked) freight cars and was cheaper than a screw coupler and was used to limit the amount of slack between freight cars.
The screw coupler was used on all passenger cars, though some used knuckle (Buckeye in UKese) couplers and on passenger rated freight cars. When coupling up screw couplers the cars are pushed together (gently) to compress the buffers and the screw coupler is tightened up so as to eliminate any slack between the vehicles. When the train loco couples up to a passenger train, the loco "sets back" so that the buffers between the loco and the first passenger car compress, the screw coupler is then tightened to eliminate slack. Unlike a North American passenger train, a UK passenger train has no slack, zero. It's one complete unit from nose to tail.
Almost all countries that had railways/railroads probably had hump yards. The still do in North America though they've all closed in the UK.
As with most hump yards the "bowl", all the yard tracks, were usually very gently sloped away from the hump and then level for something like 3/4s or
2/3rds of their final length. Something like that and it probably varied between gentle slope and no slope. Freight cars came over the hump and were braked by retarders, automatic in "modern" yards and manually operated in older yards. Once the car are sorted, they are (usually) moved over to a departure yard when the various blocks of cars are made up into a train, the caboose or these days the EOT is attached, the cars connected to yard air to charge the brake system and at some time before departure, the power is attached to the head end.
I think the original question asked if cars in North America were pushed and let to roll freely onto the rear of trains but were pushed onto trains in Europe.
The answer is "No", cars were never let to roll freely onto trains in North America. When attaching a block of cars to a train, they are always pushed by a locomotive and never let to free wheel onto the end of a train. You need to define "train" as a "train", contrary to what the media and the unwashed masses think, isn't a freight car.
On 8/29/2009 6:42 AM Christopher A. Lee spake thus:
I thought that coupling had/has to be done "manually" in any case: how else are the air hoses going to get connected? The couplers (at least in the US) will automatically couple when, say, a car is rolled down a "hump" (same here as in Yurp, apparently), but a trainman still has to come along and connect the trainline, right?
Most British steam era freight only had hand brakes on the wagons. The only brake force on a moving train was from the engine and tender, and the guard's hand brake at the back of the train.
Not 100% true. It is true that a lot of UK freight, especially mineral traffic, moved in unfitted train but there were also freight trains the were fully fitted or partially fitted that ran with a fitted head and they used vacuum brakes and not air brakes. The vacuum brake hoses had to both manual connected and disconnected, unlike air brake hose which can pull apart without damage.
These days, since the early 1980s(?), all UK trains are air braked, except a few carriages that remain vacuum braked for use behind steam excursions.
Roger T. wrote: [...] Unlike a North American passenger train, a UK passenger
Erm, Roger, on our trip to Alberta with Via last year, I noticed no slack. Several times I didn't realise were moving until we hit a rail joint (the train took siding for almost every freight train, and in N. Ontario almost all sidings had jointed track.)
"> [...] Unlike a North American passenger train, a UK passenger
Perhaps not on Via Wolf but I'm not sure about commuter trains. Besides, like the vast majority of North Americans, I don't travel by train. The last time I was on a train in North America was probably around 1975 and that was, IIRC, on the Turbo from Toronto to Dorval. :-)
On 8/29/2009 11:39 AM Christopher A. Lee spake thus:
I find this hard to believe. After all, in the US, airbrakes were standard well before the end of the steam era, and I think that the rest of the world wasn't that far off in adopting them either. (Not sure of exact dates, and sure that others will give the correct info here.)
Not that there aren't those who model pre-airbrake eras; more power to 'em. But I think it's safe to say that *most* of us model times when trains had airbrakes (and trainlines) as standard equipment.
By the way, I think you're making waaaay too much of the OP's perceived difficulties with English. His writing seems perfectly clear to me.
Most steam era goods wagons were un-braked apart from a handbrake lever. The trains trundled along pretty slowly. When they had to go up or down a hill, the brakes were pinned down to prevent running away, and thengine dragged the wagons against the friction of the brakes. Rather like driving a car with the handbrake on. The wheels would still go round but it took a lot of power.
There were vacuum braked freights which were faster but there were less of these. Typically for perishable goods.
Coal was probably the highest volume freight traffic. Prior to WW2 the railway companies could provide wagons at a daily rate, but because these would spend so much time at the colliery or the coal merchant, it was cheaper to own or lease your own.
The average coal merchant wanted a load that would fit in a short wheelbase 4-wheeled wagon. The GWR and other lines tried to streamline things with larger wagons but these were too big for the customers, as well costing more to hire per day.
The 4-wheel wagons were built as cheaply as possible, and were little more than mobile coal bins. The customers disn't want anything more than that
As previously pointed out, the only brake force for these trains came from the engine and tender, with a screw-down hand brake on the guard's van at the rear.
During WW2 all these were commandeered for the war effort. Nationalisation came after WW2 and while there were modernisation plans, things carried on pretty much as before. If you don't believe me, try to find brake hoses on this wagon built in 1948.
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This was larger than most because it was internal use, for locomotive coal. The average coal merchant still only wanted half that load.
Air brakes came into general use in the UK after the end of steam.
Passenger trains and fast freight used vacuum brakes. In the early
1980s a train I rode from Manchester to London was very late because the dual fitted (vacuum and air) failed, and the first replacement they sent only had air. This was the Manchester Pullman whose stock had been built in the 1960s
During this era newer passenger stock was air braked and older vacuum, with some of the older having both. Many nut all locomotives were dual braked. Incidentally the train I mentioned was the Manchester Pullman and the carrengines but not all dual braked, a
But coal, mineral and other unfitted freight ran until well after the end of steam.
Here's a diesel brake tender to brovide extra braking force for a diesel engine pulling an unfitted train of 10-ton mineral wagons..
Goes without saying. They use the same metal coupling or "gladhand" on the end of the airhose as we use in North America. It's a pretty universal fitting for not only for brake hoses but for all kinds of pneumatic hoses. Even the constructon crews with jack hammers use the same fitting.
You're talking passenger, I was discussing freight. And the UK is like much of the rest of the "modern" world when it comes to fixed formation trains aka "multiple unit" trains. They also use automatic air connections that are all part of the coupler. Not universally, unfortunately, which can create major problems when an m.u. (Fixed consist) train fails on the mainline and the following train has a completely incompatible coupler system so it cannot come up behind and push the failed train forward.
That's why they have or had "Thunderbird" diesels. Why "Thunderbird"? Google the TV show "Thunderbirds" and the answer becomes obvious. :-)
Nope. He's absolutely correct. The majority of British freight trains ran with only the locos brakes, the hand brake on the tender and the guard's hand brake in the brake van at the rear of the train. That's why most UK trains ran at less then 40 mph, because all the braking was in the loco and the weighted brake van at the rear.
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