Trains...

Xeon SX

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How much torque trains produce. I mean the ones that carry people or transport coal and such. Also what is their power source?
 
They are diesel electric. A diesel engine turns a generator which then powers electric motors on the axles.

I watched a cool thing on trains off the Discovery Channel a couple weeks / months back, but I can't seem to find it...
 
Just like cars it depends on the locomotive. Different locomotives are rated for different loads. You would use a different engine on the great plains than you would crossing the rockies. Anyway, they usually "stack" locomotives, running many at a time. Once they hit the mountains they sometimes put on a couple extra "helper" locomotives at the back of the train - in fact a town in Utah was named Helper for this very reason - it was a railroad town built around a yard the only purpose of which was to attach helper locomotives before a long steep grade.
 
Viper007Bond said:
They are diesel electric. A diesel engine turns a generator which then powers electric motors on the axles.

I watched a cool thing on trains off the Discovery Channel a couple weeks / months back, but I can't seem to find it...

Most trains in crowded European areas just use electricity, I guess... Only in the more remote area's diesel trains are used.

And it seems like the modern trains over here do have a small engine in every wagon too, so they can move along with 3-4 wagons without a big locomotive before it.
 
CyberMonkey: we have like billions of miles of track and an electric train wouldn't be strong enough to pull a train over a mile long. I've gotten up to a couple hundred cars before when counting the cars in trains. ;)
 
I'm not sure if the performance is the issue, but I think the building and maintenance of the electric power lines above the tracks would be impossible for very long trajects.
 
Viper007Bond said:
CyberMonkey: we have like billions of miles of track and an electric train wouldn't be strong enough to pull a train over a mile long. I've gotten up to a couple hundred cars before when counting the cars in trains. ;)
as cybermonkey points out, the cost of overhead wire is the reason why the US uses diesel locomotives. performanse is not an issue.

the most powerful US diesel locomotive ever, the EMD DDA40X, which was made by putting two regular engines onto one frame has a power output of 4.900kw.

a regular german electric freight engine, the class 152, however, puts out 6.400kw.
and an older, now out of service high speed passenger engine, the class 103 even had 7.440kw.

the power to haul those mile long trains through the US really comes from using at least three engines.


overhead wire is good in a small, congested space like europe (or metropolitan areas of the US, japan etc.) where trains run every few minutes. it reduces pollution and allows for more powerful locomotives, but its expensive to maintain and you need a power source in regular intervals. both of which would be very difficult to do throughout the whole of the US.
 
Yeah, I knew the cost was the main reason, but I figured they couldn't put enough power though the line in order to handle such large trains going like 70 MPH. :?
 
CyberMonkey said:
Most trains in crowded European areas just use electricity, I guess... Only in the more remote area's diesel trains are used.

And it seems like the modern trains over here do have a small engine in every wagon too, so they can move along with 3-4 wagons without a big locomotive before it.

Make it mainland Europe. ;) In the UK there are still not so many electric lines as here in Western Europe.
 
hajj said:
CyberMonkey said:
Most trains in crowded European areas just use electricity, I guess... Only in the more remote area's diesel trains are used.

And it seems like the modern trains over here do have a small engine in every wagon too, so they can move along with 3-4 wagons without a big locomotive before it.

Make it mainland Europe. ;) In the UK there are still not so many electric lines as here in Western Europe.
Blame Thatcher. Also the reason no trains ever run on time.
 
peter3hg2 said:
hajj said:
CyberMonkey said:
Most trains in crowded European areas just use electricity, I guess... Only in the more remote area's diesel trains are used.

And it seems like the modern trains over here do have a small engine in every wagon too, so they can move along with 3-4 wagons without a big locomotive before it.

Make it mainland Europe. ;) In the UK there are still not so many electric lines as here in Western Europe.
Blame Thatcher. Also the reason no trains ever run on time.

Your trains don't run on time because you still use a victorian signaling system on some tracks. Labour could changed that in the last years. Deregulation has had some bad effects on public transport. TfL is still far away from being great, but having one body organising everything has it's advantages. :roll:
 
I can't believe this is our only thread on trains. Obviously trains are awesome. Post your trains and discuss. I begin with the new SJ 3000, an updated Regina designated X55. Also awesome is the red house at 0:20.


Interior (1:00 in)
 
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Yeah, I knew the cost was the main reason, but I figured they couldn't put enough power though the line in order to handle such large trains going like 70 MPH. :?

There is so much more power in electric lines that you couldn't produce with any realistic number of Diesel generators (except a really really large one like on a ship).

The problem is just, that there have to be transformer stations "everywhere" to keep up the voltage. So it doesn't make any sense on tracks that aren't very busy or where there aren't any good connections to the electric grid.

I know, that here in some "rather" [nothing compared to the US] rural areas with electric tracks, there are gas-turbine power generators that produce electricity.

And diesel trains are diesel electric, because an electric motor is just better if you need a lot of torque at low rpm.

What I personally find really interesting and what must be really complicated to develop, is that "modern" electric trains like a ICE 3 use recuperation. Means if the train brakes, the motors, that are mounted in the wheels, are switched from motor to generator mode and they generate electricity. That electricity has to be transformed to the voltage of the train power line AND synced with its modulation.

And this while braking, meaning that rpm of the wheels change constantly which means that the generators output changes also constantly.

I don't know too much about electricity, but it must be really complicated to make that work flawlessly.
 
Gotta love the TGV...


Also, British Steam.


Steam engines here are still a big spectator thing.
 
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I can't believe this is our only thread on trains. Obviously trains are awesome. Post your trains and discuss.

How 'bout a thread about squashed trains? I'll start.

410001MKF_2TK_1152.jpg






As for the shallow-grave-discussion about torque and power, our modern high-speed trains have transformers and motors distributed over the train. Each half train hence is unsplittable, and as a result you have decent power and traction. About 4MW per half train, so in its longest regular operation they put down about 16MW - about 22000hp.
For transporting stuff we use electric as well, such as this 6.4MW Siemens locomotive:

DBAG_Class_152_Bahnhof_Rumeln_I.jpg


If you need even more power, just take two :dunno: comes with regenerative braking as well :nod:
 
I approve this thread.

Nothing gets me going like a big old steam locomotive.
challenger.jpg


But I also love new Maglevs.
 
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Train dragrace!


The train we're riding in is terrifically ugly X31K.


The door folds so you can link two ugly trains together. Not sure where the drivers control panel or seat goes.
 
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