Why are trains so heavy?
Why are trains so heavy?
Author
Discussion

sparkythecat

Original Poster:

8,097 posts

284 months

Monday 27th June 2005
quotequote all
The reason our railways are in such disarray is that the tracks are worn out. Hardly suprising given that tains are enormously heavy and have steel wheels.

I can understand goods trains being heavy because of the weight of stuff in them, but why do passenger carriages need all that heavy guage steel in them?

Similarly, why don't they have softer wheels? It'd be far easier to change a few carriage tyres now and again, than replace miles and miles of worn out track. After all, the Paris Metro runs on rubber wheels

As you may have gathered, I know sod all about trains

beano500

20,854 posts

304 months

Monday 27th June 2005
quotequote all
We wouldn't be in this mess without gravity...

planetdave

9,922 posts

282 months

Monday 27th June 2005
quotequote all
As commercial vehicles the train companies dont want the trains jacked up having the tyres changed that often.

And lets see....bloody big and made out of metal. Yep - reckon I know why dey is heavy, man.

sparkythecat

Original Poster:

8,097 posts

284 months

Monday 27th June 2005
quotequote all
beano500 said:
We wouldn't be in this mess without gravity...


So, now we've discovered gravity we need big heavy trains to move all the apples about?

planetdave

9,922 posts

282 months

Monday 27th June 2005
quotequote all
It must have been hell before they discovered gravity


I love the idea of Columbus discovering America. Strangely the inhabitants hadn't discovered it before. They must have been thick





[edit]for typos

>> Edited by planetdave on Monday 27th June 23:43

beano500

20,854 posts

304 months

Monday 27th June 2005
quotequote all
sparkythecat said:

beano500 said:
We wouldn't be in this mess without gravity...



So, now we've discovered gravity we need big heavy trains to move all the apples about?
Hey - don't shoot the meesenger! Take it up with Newton!

sparkythecat

Original Poster:

8,097 posts

284 months

Monday 27th June 2005
quotequote all
anonymous said:
[redacted]


I still don't really understand why it has to be that heavy. A Volvo double decker bus like this one will also carry about 80 passengers but has an unladen weght of less than 10 tons



sparkythecat

Original Poster:

8,097 posts

284 months

Tuesday 28th June 2005
quotequote all
anonymous said:
[redacted]


Fairymuff.

apache

39,731 posts

313 months

Tuesday 28th June 2005
quotequote all
It's all down to traction, modern trains are actually too light which causes several problems, wheel slip, wheel spin and leaves. Metal to metal isn't the best combination for grip so the heavier the vehicle the better the traction, braking effort and ability to break through leave mulch to provide metal to metal contact for TPWS to work (train protection warning system)


edited to add the new stuff has just under 7000bhp has 9 x 50 ton cars , minus self loading cargo and has to stop and accelerate on two narrow rails, the WSP is very active in the wet

>> Edited by apache on Tuesday 28th June 00:29

NiceCupOfTea

25,586 posts

280 months

Tuesday 28th June 2005
quotequote all
sparkythecat said:

anonymous said:
[redacted]



I still don't really understand why it has to be that heavy. A Volvo double decker bus like this one will also carry about 80 passengers but has an unladen weght of less than 10 tons


Is that an African or European bus?

8Pack

5,182 posts

269 months

Tuesday 28th June 2005
quotequote all
I believe that it was the break-up of a "resilient" wheel that caused the German ICE train to crash into the road bridge and bring it down. They went back to the solid steel wheels again after that.

Hilts

4,684 posts

311 months

Tuesday 28th June 2005
quotequote all
Think we have to learn from the Japanese and their Maglev trains (Magnetic Levitation), speeds approaching 350-400MPH, obviously with maglev weight is no longer a factor.

8Pack

5,182 posts

269 months

Tuesday 28th June 2005
quotequote all
Hilts said:
Think we have to learn from the Japanese and their Maglev trains (Magnetic Levitation), speeds approaching 350-400MPH, obviously with maglev weight is no longer a factor.




Well Hilts, Like someone on here once said to me on here, "railways are OLD technology!"

All I can say is:WOW! Yes in - "Britain" maybe!

speedy_thrills

7,928 posts

272 months

Tuesday 28th June 2005
quotequote all
Hilts said:
Think we have to learn from the Japanese and their Maglev trains (Magnetic Levitation), speeds approaching 350-400MPH, obviously with maglev weight is no longer a factor.
By no means do I know anything about electromagnetic engineering but wouldn’t a train with more mass be more likely to overcome the repulsion of the electromagnets and end up smashing into expensive stuff? So a heavier train would have to travel slower as to avoid damage.

Of course if you are going to go to all the trouble of having electromagnetic rails why not electromagnetic roads? Think about the potential for immense speed and the amount of money we could save on re-surfacing the road.

spaximus

4,365 posts

282 months

Tuesday 28th June 2005
quotequote all
I recently went to the rail museum in York where they have a Bullit train on display. A railway man was saying when these were first used in the late 1950s the british were so far behind technologically it was embarresing. We still had steam trains then, and nothing has changed at all, the japenese still have a pride in their system, the number of trains late is almost zero and up until last year they had had no accidents on the bullit train system.
We are slowly getting a high speed link to London, but nowhere else.
I have often thought maybe it would be better to pull up all the tracks and tarmac them all for bus and commercialuse only, you would probably get more use out of the area available than anything else. Only the intercity trains would really be slowed down.

Gaffer

7,156 posts

306 months

Tuesday 28th June 2005
quotequote all
The Shinkansens are fantastic, the quickest one is the Nozomi.

When I was in Japan earlier on this year, I was dreading public transport but I loved it. The trains (even the local trains) were clean and ontime, people who used them were polite and helpful, especially as everthing was in Japanese.

And now they have ones with ears:

http://news.bbc.co.uk/2/hi/asia-pacific/4621217.stm



More on the trains here:

www.japanrail.com/

Claire

I used to work for Alstom (formally GE), I had Virgin, KCR/MTR and GNER as my accounts for my sins.

>> Edited by Gaffer on Tuesday 28th June 08:21

NightDriver

1,082 posts

255 months

Tuesday 28th June 2005
quotequote all
If your bored and want to know how Maglev trains work,

[url]http://travel.howstuffworks.com/maglev-train1.htm[/url]

blindswelledrat

25,257 posts

261 months

Tuesday 28th June 2005
quotequote all
Im frankly astonished that so many people seem to care why trains are so heavy.

wizzpig

2,039 posts

257 months

Tuesday 28th June 2005
quotequote all
Hilts said:
Think we have to learn from the Japanese and their Maglev trains (Magnetic Levitation), speeds approaching 350-400MPH, obviously with maglev weight is no longer a factor.



Don't mean to nit-pick but that's not a maglev - 'tis a JR500 Series Shinkansen.

hugoagogo

23,437 posts

262 months

Tuesday 28th June 2005
quotequote all
anonymous said:
[redacted]


this probably isn't actually true, but it's amusing

" Does the statement, "We've always done it that
way" ring any bells... ?

The US standard railroad gauge (distance between
the rails) is 4 feet, 8.5 inches. That's an
exceedingly odd number.

Why was that gauge used?

Because that's the way they built them in England,
and English expatriates built the US Railroads.

Why did the English build them like that?

Because the first rail lines were built by the
same people who built the pre-railroad tramways, and
that's the gauge they used.

Why did "they" use that gauge then?

Because the people who built the tramways used
the same jigs and tools that they used for building
wagons, which used that wheel spacing.

Okay! Why did the wagons have that particular
odd wheel spacing?

Well, if they tried to use any other spacing,
the wagon wheels would break on some of the old,
long distance roads in England, because that's
the spacing of the wheel ruts.

So who built those old rutted roads?

Imperial Rome built the first long distance
roads in Europe (and England) for their legions. The
roads have been used ever since.

And the ruts in the roads?

Roman war chariots formed the initial ruts,
which everyone else had to match for fear of
destroying their wagon wheels.
Since the chariots were made for Imperial Rome, they
were all alike in the matter of wheel spacing.

The United States standard railroad gauge of 4
feet, 8.5 inches is derived from the original
specifications for an Imperial Roman war chariot.
And bureaucracies live forever. So the next time you
are handed a specification and wonder what horse's
ass came up with it, you may be exactly right,
because the Imperial Roman war chariots were made
just wide enough to accommodate the back ends of two
war horses. Now the twist to the story...

When you see a Space Shuttle sitting on its
launch pad, there are two big booster rockets
attached to the sides of the main fuel tank. These
are solid rocket boosters, or SRBs. The SRBs are
made by Thiokol at their factory at Utah. The
engineers who designed the SRBs would have preferred
to make them a bit fatter, but the SRBs had to
be shipped by train from the factory to the launch
site. The railroad line from the factory happens to
run through a tunnel in the mountains. The SRBs had
to fit through that tunnel. The tunnel is slightly
wider than the railroad track, and the railroad
track, as you now know, is about as wide as two
horses' behinds.

So, a major Space Shuttle design feature of what
is arguably the world's most advanced transportation
system was determined over two thousand years ago by
the width of a horse's ass. ... and you thought
being a HORSE'S ASS wasn't important!"