How many hours on a Diesel engine before a rebuild?

[rvos1979]

Ask the guys who run diesels in truck and tractor pulling, where some crazy horsepower numbers come out of stock size truck and tractor engines. Thing is, though, you can’t maintain that level of power for very long before you risk melting down the engine. And when it goes wrong, it goes in spectacular fashion…

[CSSHEGEWISCH]

I remember reading somewhere many years ago that the engine of a top dragster can last no more than 60 seconds at full throttle without being torn down and rebuilt. That assumes that it will last that long.

[da_kraut]

Hello everyone,

great responses, thank you everyone.

Frank

[nfotis]

da_kraut
As a result if you would get the 710 to produce power like the diesel in the pick up truck you would be looking at about 14,880hp. How long before the engine would blow up? Probably not long.

The challenge would be using all that power. On a six axle 4400 HP locomotive, the traction motors come in just over 700 HP per. On a 14,880 HP locomotive, they’d approach 2,500 per axle. And you thought the GP40’s were slippery…

Of course, if you could use that power in mother/slug configurations with six axle units, you’d be down to 1,250 per axle, but that’s still pretty hot.

Of course, that assumes that the prime mover could survive such a mod…

Not a problem.

Typical European locomotives (and the new ACS-64 for Amtrak) handle 2000+ HP per axle everyday, thank you very much.

N. F.

[Paul_Milenkovic]

I always wondered about GP-40 and its 750 HP per axle in relation to the 500 HP per axle of the SD-40. Back in the days where wheel-slip control was a skilled locomotive engineer, 500 HP per axle seemed like partical upper limit.

I especially wondered how the traction motors on the GP-40 handled all of that extra HP. What I finally realize many years later is that the GP-40 has the same fine traction motors as the SD-40. The traction motor really doesn’t have a horsepower limit as much as it as a torque limit, and the torque limit has to do with how much tractive effort the pair of wheels on an axle can exert at their rims (without slipping), which is more or less the same, regardless of the horsepower rating (2000 GP-38, 2300 GP-39 (do I have this right?), 3000, GP-40.

What the higher horsepower per axle allows you to do is supply a given amount of torque at a higher speed. Provided the torque limit is not exceeded to slip the wheels or burn out the traction motor, you can supply whatever level of horsepower you want, provided you are going fast enough.

Electrics supply insane levels of horsepower per axle – because all of that power is there for the collecting from the overhead electric wire. Of course this high horsepower only comes into play at higher speeds beyond what a drag freight operates at.

[nfotis]

The tractive effort is limited by the weight on driving wheels up to the ‘critical speed’ (typically around 10-15 mph).

If you see the tractive effort diagrams for locomotives like the Voith Maxima (same size and weight, different horsepower), you will see that the diagram is essentially shifted to the right - the ‘critical speed’ becomes higher.

Horsepower matters after approximately 20 mph or so.

N. F.

[CSSHEGEWISCH]

Electrics also have the advantage of short-term ratings, which allows those incredibly high HP ratings but only for short periods before the electrical gear is fried.

[Shadow_the_Cats_owne]

You can have all the HP in the world according to engineers. However according to real world if you can not apply that power to the ground you are just spinning your wheels. Or as my late father put it he was a machinist for Dana Corp in the 80’s you can install that 400 HP engine in your Pickup Ford. However if you don’t allow us to build you the rear end needed to hold the power your just going to snap axles in half. He worked on the stuff that was used by the SVT division of Ford.

[nfotis]

Electrics also have the advantage of short-term ratings, which allows those incredibly high HP ratings but only for short periods before the electrical gear is fried.

Today’s electric one-hour rating is nearly the same as continuous rating.

E.g. the Siemens “Taurus” has a one-hour rating of 6.4 MW on the rails(practically the equivalent of two 4400hp diesels, once you take into account losses from the generator to the rail), and a continuous power of 6 MW (if my memory is operating correctly).

Obviously, putting 2000+ hp per axle on the rail requires advanced traction control systems, but it is a daily occurence in Europe (and already on East Coast, with the Amtrak ACS-64).

Cheers,

N.F.

[BaltACD]

CSSHEGEWISCH

Electrics also have the advantage of short-term ratings, which allows those incredibly high HP ratings but only for short periods before the electrical gear is fried.

Today’s electric one-hour rating is nearly the same as continuous rating.

E.g. the Siemens “Taurus” has a one-hour rating of 6.4 MW on the rails(practically the equivalent of two 4400hp diesels, once you take into account losses from the generator to the rail), and a continuous power of 6 MW (if my memory is operating correctly).

Obviously, putting 2000+ hp per axle on the rail requires advanced traction control systems, but it is a daily occurence in Europe (and already on East Coast, with the Amtrak ACS-64).

Cheers,

N.F.

It is easy to put high horsepower to the rail when the loads being hauled are light - like Europe and the NEC. Applying that horsepower when hauling a maximum tonnage train is magnitudes more difficult.

[nfotis]

It is easy to put high horsepower to the rail when the loads being hauled are light - like Europe and the NEC. Applying that horsepower when hauling a maximum tonnage train is magnitudes more difficult.

Hmm, how about 5.000 metric tonnes? (that’s 5.512 short tons for you), like this?
https://www.youtube.com/watch?v=XfVxkiYxcgw
Using 40+ years-old electric locomotives: https://en.wikipedia.org/wiki/DB_Class_151

Okay, not big enough.
What about 8.500 metric tonnes? (that is 9.500 tons for you):
https://www.youtube.com/watch?v=a6eCgNxO-nE&list=PLB6140C681EC6E487
(stiff grades, arctic conditions)

More details about that electric locomotive: https://en.wikipedia.org/wiki/Iore
(which is the nearest thing to USA heavy haul, they even have AAR couplers if I remember correctly)

Still not satisfied?
Okay, how about the China (Daqin line), with regular 10.000 metric tonnes per train (11.000 tons) or double trains of 20.000 tonnes?
https://www.youtube.com/watch?v=91LJkrtYWw4&list=PLSdpxvzv4y8JAicjYPRHJCEc-lNwC26j6
(with &

[D_NICHOLS]

Ask the guys who run diesels in truck and tractor pulling, where some crazy horsepower numbers come out of stock size truck and tractor engines. Thing is, though, you can’t maintain that level of power for very long before you risk melting down the engine. And when it goes wrong, it goes in spectacular fashion…

I can do that one better. Take a Cummins 8.3L Diesel engine and see how long it will last at full load. Factory rated at about 195 HP Gross for 8 hours a day operation. Then run it at that for 24/7. Time between rebuilds, 2500 hours. The turbo and the exhaust manifold will be as red as the Enter Now Win a Drone sweepstakes button.

A vehicle engine drops by 1/2 the HP rating going from a vehicle to an industrial use.

A Detroit Diesel in the 71 Series was expected to last 7000 hours of operation in a truck. We got 14,000 hours out of ours because we ran them at a steady speed of between 1400 and 1800 RPM at 50%-75% load in industrial use.

[nfotis]

Forgot to put another document for your perusal:

http://www.stadlerrail.es/media/downloads/pdfs/flyer/EURO_DUAL-_EN_July_2012.pdf

Note the shift of the expected tractive effort to the right, thanks to the higher power (1 MW = 1341 hp), for 1 MW (diesel), 2.8 MW (diesel) and 5 MW (electric).

As you can see in the diagram, you can haul nearly the same tonnage at higher speeds (the critical speed, where the knee between the weight-limited tractive effort and the power-limited tractive effort, shifts to the right)

N.F.

[FlightPlan]

We had an older tier 2 Evo in the shop recently that shot a rod out the block. The engine was 11 years old and not even on the overhaul list yet. The only thing holding it back was the megawatt hours being only 25000 or so. Was told this was allow because the unit had a lot of out of service credit time. If it was a “hard” 10 years on replacement, this engine would have been replaced previously and probably prevented a large failure from taking place.