Bogie exchange: not just for railways fans.
Railways cover entire continents. One day you could start in Lissabon tasting Porto
in a train's bar, reach Berlin and get some Jägermeister there, proceed
farther east and a couple of days later, reach Moscow, get well warmed by Vodka and finally,
head for China. Is that all as easy as you may think? Not really. Simply speaking, it won't work
- at some point you either stop or derail. For the tracks are different.Most of the world's railways is using the "standard gauge", which means the distance between the inner sides of rails is 1435 mm. All countries in the former USSR have the gauge that is slightly wider - 1520 mm. (Finland has 1524 mm gauge, Spain and Portugal have 1668 mm). This is simply historical. Long time ago even in different US states different gauges were in use, until the final unification.
So, what do you do when different gauges meet? The first solution was of course to have two sets of tracks and reload cargo and have the passengers to change their coaches. Then came the era of mass travel. We simple people are lazy and don't want to pay tips for reloading our bags. And we demanded new solutions.
The most high-tech thing is variable gauge axles. Those can be adjusted when the train enters another gauge area. Nice and expensive, and not really suitable for high-speed trains. High-speed trains require precision mechanics. Today, variable gauge axles hold the maximum of 250 km/h - nothing special for French TGV trains (300 km/h is its normal speed).
In border areas, you can build tracks with double rails ("dual gauge"). Again not the most cheap solution. And who needs European tracks in Siberia?
Yet another solution? Look at how this is being done at the border of Poland and Belarus. First, you of course build a station with two sets of tracks. Passengers that don't want to wait for gauge conversion can disembark here and get lost. The rest is waiting for bogies (paired axles - total four wheels) to be exchanged, without leaving the sleeper cars. The Brest station is in the upper right corner on the following map at Google. The northern side has two tracks with standard gauge.
View Larger Map
So, the train arrives and, after a short stop, retreats to a kind of hangar where the magic happens. The building is in the bottom right corner of the first map, and on the next one, it's zoomed in. You can even see the train entering (or leaving) the bogie exchange!
View Larger Map
If you look again, you'll notice, right "above" the train, the bogies stock (the rows of smaller dark objects), waiting for their turn.
Okay, enough theory, let's see the action! The following set of photos is made during two exchanges we were on on our last vacation. That was on late evening and very early morning, making the photos blurry but adding more magic.
The exchange has three lines, so the train cars are being decoupled to fill all of them. This is our train:
And we go back and forth many many times...
until we arrive to big jacks waiting to lift us (pictured is defunct exchange line that was free):
The canal between the rails has a chain running to transport the bogies.
Don't forget to apply enough lube on the threads:
...And, just push the button!
It goes up! How heavy is it? The signs said about 100 ton net weight. Add passengers and their stuff. It will be slightly more (or even not slightly if my wife is packing the bags).
See the jack in action. Actually, it seems to be operated by this smallish electric engine at its bottom (left).
Come closer to see the sleeper car flying at half a meter above its bogies.
New bogies are coming! They are transported by the chain running between the rails, as I said, and the staff stops two bogies under each car.
Each bogie is detached from the batch, moved by one-two meter from the batch running further and then carefully positioned. Seven ton. No mechanics here. Just two men. Real men, I mean, not us keyboard slaves. (One image on Wikipedia - see links below - shows this being done by just one person).
And the guy pushes the button again, and we start the descend!
After a short stop few centimeters above the bogie for eventual repositioning, the final descend and we are done!
More to explore at Wikipedia: Rail gauge article, article on Bogie Exchange
