Steam Tractor on Dynomometer - Torque and HP Explained

120 HP Rumely steam tractor power test on Prony Brake. This tractor can produce over 3,000 ft-lbs of torque between 0 and 250 RPM.
Filmed at the Western Minnesota Steam Thresher's Reunion steam show in Rollag, MN USA on 9/1/2007. For more info on this show, go to rollag.com. (more) (less)

Category:

Autos & Vehicles

Tags:

• steam
• tractor
• traction
• engine
• rollag
• wmstr
• prony
• brake
• dyno
• dynomometer
• torque
• horsepower
• HP

[marcgallegos]

lets see a watermelon-sized electric motor pull a twelve- bottom plow,

[Clockmaker46]

Man, those old Rumelys were some awesome machines. Thanks for sharing this.

[EETechs]

@Polybun Not necessarily true. If it is a high frequency design motor like those used in aircraft then it is quite possible to have 300 HP continuous duty and be the size of watermelons. Ever heard of 400 Hertz AC induction motors? The motors you are referring too that weight 2 tons are 60 Hertz AC induction motors.

[goglesux]

@14omega28ok

:) you think just like me.

Thats why i would prefer of reviveing the opposed piston 2 stroke diesel topology, with the ability to disengage the compressor via a clutch, and let a turbo wrk afterwards. Most probably more than 1 turbo to enable low RPM spool up. And a hull hydraulic drive chain.No diff, no clutch,no semi-axle.Variable pump and hydro motor.End of story :) CVT would rock.

[14omega28ok]

@goglesux So? I'd rather a slow powerful machine that will get the job done over a fast machine that won't

[goglesux]

@14omega28ok

yupp, bust most peeps do not realy understand how can something with 120 hp be stronger than a 150 hp thingy.

it can, but it will do the job slower.

[14omega28ok]

@goglesux this thing is almost direct drive I think, So yes that 3,000 Ft lbs of torque definitely matters.

[goglesux]

yes, i know rpm hp and torque are in direct relation.

i just wanted to point out that hp alone is meaningless.

so is tourqe, naturaly.

but anyways, just cuz its only 120 hp, there is nothing wrong with it.

knowing steam engines (piston ones) are not realy a high revving construction one might suspect low rpm, so hp will be low too. but you get a lot of torque, and thats what an external combustion engine is ment to do.

[phtmexplo]

@goglesux U can also say the opposite : why torque is not important if u have alot of HP, if u have an engine that goes up to 1.000.000 rpm (example) torque is nearly irrelevant. Try stopping that thing lol.

HP = torque x 5252

But u are right too btw :)

[goglesux]

good example why horsepower is irrevelant for many tasks.

there is a relation between rm, hp, and torque.

for a tractor engine, best to have somewhitng that has a huge tourque reserv.

that means tourqe does not drop suddenly with rpm.

this engine does 250 rpm, and the torque is -i would think- quite constant for a huge range -compared tot he 250 rpm redline-.

120 hp does not seem a lot, but it actualy does not make any difference.

love it, love it, love it.

[Fortsand1]

All I saw was the belt removed and reinstalled three times, what a bummer!!

[crxgen1a]

i like how youtube messed this up. seems old timey with the people moving fast