Trains vs trucks...

[rusty ol ranger]

A few of us drivers were BS'in yesterday while we unloaded, somehow we got on this debate...

Do you guys think an slightly above average OTR tractor (say a 500hp pete with a 13sp) could move as much as a train can? Not for distance, but even get it rolling? Assuming traction was a non issue...

The trucker pride in me says yes, but the logic side of me says no...

Discuss

 

[planeflyer21]

Maybe.

In Australia they have those "truck trains." The trucks seem to be quite a bit beefed up though.

 

[rusty ol ranger]

Maybe.

In Australia they have those "truck trains." The trucks seem to be quite a bit beefed up though.

Yeah, im aware of those, but i dont think they carry anywhere near what a freight train does....i could be wrong tho

 

[pjtoledo]

no. at least not with a regular drivetrain & gearing.

train locomotives are powered by electric motors that produce maximum torque at zero RPMs. they don't have to be concerned with burning up the clutch or shifting gears.

 

[Captain Ledd]

Those trucks in Australia also have a pony-truck device thing. It's basically a dolly with an engine.

It still depends on the train too. Are we talking about a mile and a half loaded coal train or something that's got 4/5 locomotives on it? or just what one average locomotive can do?

On a true, perfectly flat surface I say it has a chance, but the clutch/converter won't be happy about it.

 

[rusty ol ranger]

No, i was talking 1 train against 1 truck. No way 1 truck could move what 5 trains can, shoulda been clearer on that.

No doubt youd be in for a clutch job after trying.

 

[adsm08]

No. For one thing, HP means fukall when getting a load rolling. Torque is the number you need to look at there.

Some of those freight diesels are running V12s that make your Pete look pathetic, and they are using them to run the generator that powers those electric traction motors PJ mentioned.

The question that should be getting asked here is, why oh why are we not applying this tech to cars yet?

Jeep built a prototype that didn't get far from the drawing board. It was a "hybrid" Wrangler. It had a little 2-cyl lawn mower engine that was used to run a large generator that powered an electric traction motor. I think that was still run through a transmission of some sort, but the engine had no physical connection to the wheels.

 

[rusty ol ranger]

How much torque does one of them train diesels make? Obviously i know that the torque from the electric motors move stuff, but im just curious.

A 500hp cummins is right around 2000 ftlbs assuming its a ISX 15, the older N14s were a bit less

 

[adsm08]

How much torque does one of them train diesels make? Obviously i know that the torque from the electric motors move stuff, but im just curious.

A 500hp cummins is right around 2000 ftlbs assuming its a ISX 15, the older N14s were a bit less

I can't find the diesel engine's flywheel torque for any of the common use locos I am familiar with.

An EMD SD70MAC uses a 710G3C-ES 16 cylinder diesel. That loco can put down +175,000 Ft Lbs at the wheels for launch. Then they scale back to only 137,000 by 12 MPH.

I spent a while looking for those numbers too. The only thing I can find on the power rating of the engine is that the current model V16 710s are putting out about 4300 horse.

 

[rusty ol ranger]

I can't find the diesel engine's flywheel torque for any of the common use locos I am familiar with.

An EMD SD70MAC uses a 710G3C-ES 16 cylinder diesel. That loco can put down +175,000 Ft Lbs at the wheels for launch. Then they scale back to only 137,000 by 12 MPH.

I spent a while looking for those numbers too. The only thing I can find on the power rating of the engine is that the current model V160 710s are putting out about 4300 horse.

Holy shit.

 

[RonD]

No, a tractor can't pull as much as diesel locomotive, even an older locomotive.
But it could pull some railcars around, level ground, can't guess how many
Then STOPPING THEM is also a big deal, lol

They use smaller tow vehicles to move railcars around the yards, they are basically tractors, even have rubber wheels so they can leave the tracks and move to another track to move other cars where they need to be
They just have added retractable steel wheels, but still use the rubber tires for traction

Almost all locomotives are diesel-electric now, electric motors drive the wheels, diesel engine drives alternator/generator for the electricity, locomotives topped out at about 6,000HP back in the 1990s according to this: https://en.wikipedia.org/wiki/GE_AC6000CW

Newer ships are made that way as well, diesel-electric

So the diesels can run at consistent lower RPM after train/ship is up to speed

 

[hank857]

dont understand, do you mean move a freight train loaded or move just a basic empty train?

On diesel brothers on the tv they built and then pulled a loco and some cares (loaded?) for a bit. the truck was built and it did pull the unit. I think it was an F650/750 I cant remember. Dont forget a small pu pulled the 747 on smooth level ground also.

As to pulling a load as much as a train does, no the truck cant but it also does not have the drive train that loco does either. Besides how would it pull that much on the local roadways? Just saw a engineering program on the science channel on the Mack trucks using what appear to be cummins engines in australia. said all the components are basically custom built for the truck with the engines having I think they said 600+ HP. All kinds of stuff is included in the design. I THINK IT MAXED AT 100000 B LOAD.

 

[Curious Hound]

Another issue is that the train is on steel wheels rolling on steel rails. The rolling resistance is greatly reduced for each set of wheels, making things more efficient. All that flexing of rubber tires with steel and fabric belts on the truck wastes energy.

Some of those railroad diesels also run opposed pistons in each cylinder. They really pack a punch. Could a truck move several rail cars? Of course. But trucks and trains are designed differently and serve similar purposes in different ways.

Sent from my SM-G960U using Tapatalk

 

[Dirtman]

The small tractors we had to move aircraft when i worked in the national guard used ford 300 straight six gas engines and those things could pull massive aircraft. They only moved at about 4mphs though and the transmission/diff was gigantic. I have no doubt a modern tractor trailer engine could have enough power to pull a small train load, but I doubt the transmission could. One rail car can be more than 4 full trailer loads... Add 20+ cars and youd need better gearing that what a standard semi has.

 

[pjtoledo]

a few years back, well, probably 35 years ago I seem to remember a Ford commercial where a new pickup was pulling a few rail cars.

I have no doubt a semi could get 10 rail cars moving, but a full train of a mile in length is a different story.

however..... trains can use a trick to get long loads moving. they either engine brake or backup so all the cars are tight against each other, no play in the couplings. that way as the engine starts it's only pulling the first car. then a few inches later the combination of engine and first car grab the second car, a few inches later E + 1 + 2 grabs the 3rd car and the process repeats until all cars are moving. you know they are doing this as the bang, bang, bang moves along the train.
in low budget warehouses with tracks along side the building it's not uncommon to use a forklift to push the car to the next door. they jam a tong against it and sit there spinning the tires for a couple minutes until it moves fast enough to get to the next doorway. way back in 1972 while on a temporary job at one of those warehouses I had the job of stopping the rail car by putting a block of wood in front of a wheel. the freakin' thing was only going about 1/4 MPH and as it hit the block it just rolled over the top of it, took about 20 seconds for 1 wheel to roll over a 4x4. kind of a big slow motion crunch. best lesson in inertia I ever had.