Pulling a train is......

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MattCo

Platinum Member
Jan 29, 2001
2,198
2
81
Originally posted by: jcovercash
Originally posted by: sao123
Originally posted by: amdskip
I knew this because my uncle is an engineer for UP in Texas.

CSX + BO + Chessie + Conrail >>> Union Pacific + Santa Fe

NS > *

Thats who Im a conductor for....

Are they REALLY better, or do you tell yourself that to make yourself feel like you made the right decision?

-MC
 

LordMorpheus

Diamond Member
Aug 14, 2002
6,871
1
0
They call them diesel-electrics for a reason. I guess I would know that, though, seeing as my uncle is huge into model railroads and gave me sets and cars over the years.
 

Howard

Lifer
Oct 14, 1999
47,982
10
81
Originally posted by: otispunkmeyer
two stroke engines for the win!

in theory you can make 2x the power of a similar 4 stroke since 4 strokes only take in air every other cycle, where as 2 strokes do it every cycle.

what i think is crazy though is this......

you can actually get a "free" super/turbo charger effect if you can make your engine suck in air at a really high rate. F1 engines have roughly 120% volumetric efficiency.....that means an extra 20% of air is being forced into the engine, and this happens simply because the engine is sucking in huge amounts of air, and at a high rate.....the momentum of the air (1m^3 air = 1.2Kg) literally forces more air into the cylinder before the valves shut.

my lecturer said if you really try, you can get 140% volumetric efficiency....basically gives you a nice power boost for nothing
Pretty sure this only happens at speed.
 

Slickone

Diamond Member
Dec 31, 1999
6,120
0
0
Wow, 710 cubic inches per cylinder.

We're about to get rail commuter service here in mid. TN. Wonder if the trains will be that nice looking.

Originally posted by: Scarpozzi
Diesel locomotives use electric motors because when you're pulling that many tons of weight, it would spin uncontrollably as well. With an electric motor, the voltage can be increased slowly enough and incrementally enough to get the wheels turning with minimal slippage.
Maybe that's another smaller reason, but that was not the reason howstuffworks stated. Also they use sand for that.
 

sohcrates

Diamond Member
Sep 19, 2000
7,949
0
0
just learned this last night while watching modern marvels - worlds largest machines on the history channel

diesel engine drives AC motors on each axle which allow independent control of each set of wheels to minimize slippage and increase power

pretty cool stuff i never knew about
 

Demon-Xanth

Lifer
Feb 15, 2000
20,551
2
81
Originally posted by: otispunkmeyer
two stroke engines for the win!

in theory you can make 2x the power of a similar 4 stroke since 4 strokes only take in air every other cycle, where as 2 strokes do it every cycle.

what i think is crazy though is this......

you can actually get a "free" super/turbo charger effect if you can make your engine suck in air at a really high rate. F1 engines have roughly 120% volumetric efficiency.....that means an extra 20% of air is being forced into the engine, and this happens simply because the engine is sucking in huge amounts of air, and at a high rate.....the momentum of the air (1m^3 air = 1.2Kg) literally forces more air into the cylinder before the valves shut.

my lecturer said if you really try, you can get 140% volumetric efficiency....basically gives you a nice power boost for nothing

The increase in volumetric efficency comes from the "ram effect" caused by the pulses from the valves opening and closing bouncing off of the intake runner's opening and coming back into the valve. The runner length and size tunes the RPM at which this happens. Most cars feature an intake designed with a plenum style for just this reason.
 

sharkeeper

Lifer
Jan 13, 2001
10,886
2
0
Diesel locomotives use electric motors because when you're pulling that many tons of weight, it would spin uncontrollably as well. With an electric motor, the voltage can be increased slowly enough and incrementally enough to get the wheels turning with minimal slippage.

We use cycloconverters for this.
 

elektrolokomotive

Golden Member
Jan 14, 2004
1,637
0
0
Originally posted by: compuwiz1
Originally posted by: elektrolokomotive
Umm...

I've got nothing here.

Sure you do, you have now increased your worthless post count by 1. ;)

Have you been counting? Please give me a breakdown worthwhile/worthless. Because as you can see from my stats, i'm really just in this for the post count.
 

natto fire

Diamond Member
Jan 4, 2000
7,117
10
76
Did you know electric motors make the most torque at 0 RPM? Also the air in the train's air brakes is keeping the brakes off. Large springs clamp the brakes if the air is let off.
 

Squisher

Lifer
Aug 17, 2000
21,204
66
91
Gone Dead Train
Nazareth
(Expect No Mercy)

It's a gone dead train
Yes, it's a gone dead train

My engine was pumpin' steam
And I was grindin' at you hard and fast
Burnin' down the rails, tryin' to heat the way
Haulin' ass and ridin' up the track
And I laughed at the conductor who was tellin' me my coal
It would never last

But then the fire in my boiler
Up and quit before I came
Ain't no empty cellar
Like a gone dead train

Once was at a time when I could
Mama shave 'em dry
And raise a fever ice-down chill
Waitin' at the station
With a heavy loaded sack
Savin' up and holdin' just to spill
Shootin' my supply through my demon's eye
Instead of holdin' my time, I hope I will

But then the fire in my boiler
Up and quit before I came
There ain't no empty cellar
Needs a gone dead train

Yes it's a gone dead train
I'm gonna teach it to learn now, now
It's a gone dead train
Yes it's a gone dead train
I'm gonna teach it to learn now, now
It's a gone dead train
Gonna teach it, gonna teach it to learn

There ain't no easy day
When your daily run's a downhill pull
And there ain't no easy way
Wishin' for some jelly roll
There ain't no switch been made
To make your juicy lemon find
A spring to run a dry well full

But then the fire in my boiler
Up and quit before I came
Ain't no empty cellar
Needs a gone dead train


Yes it's a gone dead train
I'm gonna teach it to learn
You know it's a gone dead train
Gonna teach it, gonna teach it to burn
It's a gone dead train
It's a gone dead train, you gotta learn
It's a gone dead train
Gonna teach it, gonna teach it, gonna teach it to burn.
 

Slickone

Diamond Member
Dec 31, 1999
6,120
0
0
Originally posted by: Captain Howdy
Also the air in the train's air brakes is keeping the brakes off. Large springs clamp the brakes if the air is let off.
Many roller coasters work the same way.