It puzzles me that this dangerous and slow system would have been eliminated by now and replaced by a system similar to America’s and other nations that have an automatic set-up. Does anyone know the history/background for this?
Why do you call it dangerous?
European railways have had a standing committee tasked with developing an automatic couping/uncoupling system for more than 100 years. It might be the oldest standing committee on earth. So far no product has emerged that everyone will agree too.
RWM
Having been in europe a few years ago not all equipment is link and buffer coupling ( As one carman told me). One the western bristish lines uses US Knuckle couplers on its unit coal trains. It was pecular to see a knuckle coupler on a loco with provision for the old system. Eurostar, TGVs, and other high speed units use a system similar to NJ transits EMUs. Also most commuter multiple units use some kind of automatic couplings.
It seems to work them. Why fix something if it isn’t broken?
Not sure it’s all that slow as I’ve been on trains where the engine was uncoupled and another coupled within minutes as the train reversed direction in stub terminals. The buffers are not static, they expand when the link is in place to eliminate the slack.
It’s dangerous due to the fact that a crewmember has to stand in-between moving cars to make a manual coupling. It’s inefficient because he has to couple every car by hand and it slows down the work. It limits the tonnage that can be assembled into a train; the chain link is not as strong as an AAR coupler.
I suspect Railway Man has it - they simply can’t all agree on one solution. In some ways, that doesn’t surprise me.
The “buffer and Chain” couplers are not as wide spread in Europe as the knuckle coupler is in North America. It still is the “old standard” but Europe has a much bigger variety of coupler systems than North America. Europe seems to have drifted from a truly standard coupler like the USA still has. In some countries the buffer and chain coupler is mostly used on older passenger trains and on freight trains. The Russian coupler is also used on heavy unit trains in Germany, Sweden and other countries. The American style knuckle couplers are used on heavy freight in Sweden and the UK and on passenger trains. Varius versions of the scharfenberg coupler seems very commun with passeger trains all over Europe.
Some advantages to the buffer and chain is the adjustable slack. The screw can be tightened ((by hand)) so there is virtualy no free slack. The can make for very smooth runnung freight trains. At the same time the screw can be turned back to add slack for underpowered heavier trains and\or tighter curves and for switching. The Scharfenberg couplers have also no slack.
I think the buffer and chain coupler is dangerous at the hump yards when switching, employees have to be between the cars to couple when cars role into the bowl. And then get out before the next car roles in !
I don’t think anyone moves between the cars to couple them until the track is blocked and ready to be pulled. Don’t forget that in North America they have to go between the cars to couple the air hoses, so the difference isn’t that big. My understanding is that most of Europe had agreed on a standard, but that SNCF balked at the expense.
Perhaps they will come up with a large version of the X2F horn-hook coupler![:D]
My [2c] is that those couplers are used on lighter trains (passenger or small freight) because there isn’t a need to have a more robust coupler. US cars are much heavier (even empty) and can haul more load (weight) than most of their European counterparts, correct? That would necessitate a stronger coupler. Why use a Class V gooseneck trailer to haul one Jet Ski?
If that comittee (coupler design) needs inspiration…look at Kadee![(-D]
That would be a PITA to uncouple.
Just use a really big screwdriver!
Last time there was a serious try to change this was in the 70’s. Back then it was too costly to go over to a new system wholesale. Remember, railroads like Deusche Bundesbahn had at that time well over 100.000 cars on the roster and were not yet free of steam too.
Just about all new construction since then has had a provision for automatic couplers build in its frame. And remember this also: only since the mid 90’s have most major freight routes been upgraded to 22.5 metric tons axle loading. Everything is apparantly still within design specification of the system. Ore trains from Rotterdam in the Netherlands to the steelworks at Dillingen in Germany’s Saarland use therefore 3-axle trucks (and automatic couplers on the cars and German electric locomotives in Germany but special intermediate cars with both type of couplers in the Netherlands with the Dutch diesel locomotives)
At hump yards normal practice, as far as I am aware (I only occasionally pass the last one in the Netherlands), is to bring a freigth train to a standstill, loosen the chains and later on push the train over the hunp. At the hump people with poles will lift up the chain from the hook. Of course you try to minimise this so groups of cars going to the same destination probably don’t get their chains loosened.
greetings,
Marc Immeker
welcome to an example of, “That’s the way we’ve always done it”. Railroads are not known for pushing the envelope on new technologies most of the time and with some reason. what if a new superior coupler came out that required the US railroads to convert every piece of equipment. The only possible way it could be implemented is if it was compatible with the current coupler. The new one would be phased in over ten or twenty years not overnight. If it isn’t compatible it doesn;t stand a chance
Thank you all for the very good discussion on this. According to Wikipedia, the reason why the US has a “superior” system as compared to buffer and chain coupling is that Congress forced the railroads to adopt an automatic system and eliminate hook and pin coupling. I guess when you have a gillion little nations and they can’t agree on anything, I shouldn’t be surprised to see a lack of uniformity. However, I would’ve thought that the UK would have been more inclined to go their own way on this and adopt a different standard.
I’ve lived in Germany for almost 20 years now, and the buffer and chain coupling is still predominant. The German DB began using something similar to knuckle coupings on heavy freight such as ore unit trains in the late seventies.
As far as safety is concerned, most yards are flat and switched by locomotives. I have a DB rules book, and it is absolutely prohibited to stand between the rails while a car is being shunted for coupling. The official practice is for the switcher to push the car/cars up to the car with which it is to be coupled until the buffers are not only touching but are pressed in several inches. Then, a yardworker ducks under the buffers, hooks up the chain, tightens it, hooks up the brake pipe hoses, then ducks back out. This process is really not significantly longer than hooking up the brake pipe in the US.
The buffer and chain coupling provides for smoother passenger operations due to less slack, in particular in push-pull operations. As has already been mentioned, though, most modern passenger equipment uses Scharfenberg couplers, which not only provide a mechanical, but also an electric and pneumatic connection between cars. Most of this equipment has multiple powered axles throughout the train as opposed to a locomotive and cars with unpowered axles.
If I recall this correctly, the heavy freight knuckle couplers also have a built in pneumatic hook-up. I could just as well ask why North American Railroads do not adopt the DB style couplers, as this would save time and be safer than having a guy go in between cars to hook up hoses.
And then there’s European screw couplers. Jeez, I nearly blushed! When and where were they used? Maybe they still are. That system always looked like a real chore.
What does the Darjeeling-Himalaya use? I’d like to know before riding that road even if only in my dreams.
RIXFLIX
Opinions would seem to be split on this, and it seems the people who’ve never witnessed European screw couplings in everyday use that label their use dangerous and inefficient, whereas those who have seen them in use, are quite relaxed.
Yes, it seems that more and more bulk product freight wagons are being equipped with some form of automatic coupler, but US fans have to realise that the overwhelming majority of UK freights run as block trains from origin to destination with very very little intermediate shunting (sorry, switching) work needed. Very often, the only time such a block train might need to be split is when an individual wagon needs to have a regular inspection.
So what about Buffers?
Can RWM or anyone else explain why they don’t seem to have been used/accepted in North America?
Hwyl,
Martin
Several thoughts -
Since North American couplers are self-locking, there is no need to maintain any sort of tension on the connection.
Part of the buffer function is provided by the draft gear, particularly in “Cushion Underframe” type installations.
Drawbar installations (rather analagous to the concept of running trains as solid blocks all the time) are generally not well liked. Even unit coal trains, which tend to run as solid blocks almost all of the time, use couplers instead of drawbars, even though drawbars might reduce slack action and the possibility of a broken coupler.
Just my take on the issue.