how much hp and tq does a steam train have?

[Chris142]

My new bride and i are at the grand canyon. We rode the train from williams az to the canyon. I was a little disapointed in that we were being pulled by a diesel electric engine.

But i just saw and learned that we are going back to wiliams by steam power! I checked out the site but its not supported by my phone. I was just curious as to its hp and tq.

 

[Chris142]

http://www.thetrain.com/the-train/train-equipment/

 

[Shannow]

Steam can give full torque at zero speed, which is zero HP.

Under load, the "horsepower" can be calculated from the tractive effort multiplied by the speed (sort of like using ET and vehicle weight to calculate HP on the dragstrip).

If you are going on locomotive 4960 (a 2-8-2 configration, little wheels- big wheels- little wheels), it has a tractive effort of 52,300lbs...consider it a winch cable, and imagine what it can pull, at what speed, up what grades...

I can't tell you much other than it will smell like fries.

 

[DuckRyder]

Originally Posted By: Shannow
...

If you are going on locomotive 4960 ...

I can't tell you much other than it will smell like fries.


Because it runs on waste vegetable oil.

It should be a cool ride, I was interested in riding it when we were out there, IIRC they said they had 2 more under restoration and conversion so it may not be 4960.

 

[Phishin]

The Nickel Plate 765 is only a few miles from my home. It's the engine that "The Polar Express" is built from. It is the Polar Express.

And my 8 year old son LOVES IT. And so do I The team of old guys who maintain it are SUPER friendly...you can climb all the way through it any time you want.

The engine weighs 400 tons!!! It can go 70MPH. Estimated horse power is about 5000. Tractive Effort is 64,000 pound feet

 

[A_Harman]

Measurement of steam locomotive power was never a reliable pursuit because they had different measures: boiler HP, cylinder HP, and drawbar HP. The best measure that most closely described how much power the locomotive was putting out was drawbar HP, which is measured by a dynamometer car. This was a railroad car that was placed behind the tender and had accurate instruments to measure drawbar force and road speed.

Since power is a generic measurement of the rate at which work is being done, if you know the amount of effort being applied in the direction of motion, and the rate of motion, you can calculate power. James Watt is the man who actually defined the unit "Horsepower" when he was developing steam engines in the early 1800's. He defined it by measuring the amount of continuous pull that a horse could exert (181 lbs) and how fast the horse could travel while applying it (180 ft/min). Multiplying these quantities, Watt defined a Horsepower as being 32580 ft*lbs/min, which he rounded to 33000 ft*lbs/min. (Or since there is 60 seconds in a minute, a Horsepower can also be defined as 550 ft*lbs/sec.)

So taking Shannow's example of engine 4960 being able to exert a drawbar pull of 52300 lbs, and assuming it can exert that pull at a speed of 30 mph (equal to 44 ft/sec), you can calculate Horsepower:

52300 lbs * 44 ft/sec * (1 HP / 550 ft*lbs/sec) = 4184 Horsepower

 

[JHZR2]

and 4000HP is probably around what the diesel and GT locomotives have made in recent times. May be wrong though...

 

[datech]

My uncle gave me a bunch of train magazines and yeah, 4000 hp is pretty typical. There were some made up to over 6000 but they weren't as successful because of wheel slippage. The smaller switcher types might be a couple of thousand hp.

Sometimes they use locomotives without the diesel genset linked to a regular full unit to distribute the tractive load on more wheels.

I don't know how you would calculate the hp in that situation, the diesel part is generating all the electric power but multiple electric motors are used to drive the wheels.

 

[doitmyself]

Originally Posted By: Phishin
The Nickel Plate 765 is only a few miles from my home. It's the engine that "The Polar Express" is built from. It is the Polar Express.................

Oh, yeah?? Probably just like you Hoosiers claim that John Dillinger and other gangsters hung out at Crown Point and Cedar Lake????? Oh. wait a minute, this is actually true.

Regarding the Polar Express, our Pere Marquette 1225 also claims bragging rights to the Polar Express movie: http://www.trainweb.org/tracksideonline/Program137.html

I have been in the 1225 engine house numerous times during tear downs. Both the 1225 and 765 are awesome to see in action.

 

[Chris142]

We are on 4960.its being "helped" by a diesel electric

 

[Chris142]

A bunch of outlaws just robbed the train! Lol

 

[wvrailroader]

Most of our locomotives in the coalfields and mountains of WV are 4400HP. We have some 6000HP units though. Wheel slip is not really a problem on these units because the computer software which controls the AC traction motors will not generally permit wheel slip. It operates right at the edge of slip, sort of like traction control in a car. When it detects a wheel about to slip, it dials back the power just enough to prevent it. Some of the 6000HP units have been de-rated to 4400HP, not because of wheel slip problems, but to lessen fuel consumption.

 

[The_Jeff]

Originally Posted By: Chris142
A bunch of outlaws just robbed the train! Lol

You should come to NH for the tourist trains! Clark's Trading post has a hillbilly in a model T shooting blanks and yelling at the train passengers about various injustices. And if you take the Mt Washington cog various mangy hippies (not on the payroll) moon the cars...