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Gregory Wallace
09-14-2003, 03:15 AM
What does "de-rated" mean, as in GE CW44-6 (de-rated AC6000CW)?

Thanks,
Gregory

E.M. Bell
09-14-2003, 03:29 AM
The AC6000's suffered from a plethera of mechanical problems, the most serious being vibrations from the new 6000 HP prime mover. From What I have read, GE has been replacing the prime movers in those units with the tried and true 4400 HP FDL as warrenty work for CSX and UP, thus the term "de-rated"

EB

Robert28
09-14-2003, 05:45 AM
Hey Gregory,

Here is a link to give you a run down on which CSX units are de-rated and which are not. The CW44-6's are de-rated and the CW60AC are still 6000hp units. Not many of them left.

Robert

http://www.bullsheet.com/RosterMenu.html

Guilford350
09-14-2003, 01:02 PM
Here's a true CW60AC that I caught up in Selkirk, NY: http://naphotos.nerail.org/showpic/?photo=2003081819561624831.jpg&order=byposter&page=1&key=miketv

Lord Vader
09-14-2003, 05:59 PM
Only one unit was re-engined and that was so GE's design engineers to dissect it to find stress points. They seem to have found them, as many of the derated units are being "rerated" back to 6000 & 6250 HP.

E.M. Bell
09-14-2003, 06:25 PM
Perhaps GE could take the Next Logical step into improving their product....yank out them FDL's and replace with a EMD prime mover... that would be a start....and would mean a lot less buisness for the local fire depts's across the country that keep busy putting out flaming GE's

:twisted:

Gregory Wallace
09-14-2003, 06:28 PM
Perhaps GE could take the Next Logical step into improving their product....yank out them FDL's and replace with a EMD prime mover... that would be a start....and would mean a lot less buisness for the local fire depts's across the country that keep busy putting out flaming GE's

:lol: :lol: :lol:

If I ever get my old high-school band back together, I'm gonna call us the "Flaming GE's".

~Gregory

iCe
09-14-2003, 11:14 PM
:shock: :shock:

forums are so active now! :D

mojo628
09-15-2003, 03:15 AM
The ICE-man helps spread the word.

oltmannd
09-17-2003, 01:18 PM
Only one unit was re-engined and that was so GE's design engineers to dissect it to find stress points. They seem to have found them, as many of the derated units are being "rerated" back to 6000 & 6250 HP.

Glad to here it. Derating is one of the stupidest things Mechanical Depts like to do. It saves them bucks, but wastes tons of capital. The RR paid for that HP, better to keep on the builders backs and get it fixed than give up and derate.

-Don

Guilford350
09-17-2003, 08:49 PM
But do railroads really need a 6000 HP locomotive? Say if there were two CW60AC's on a 16,000 ton coal train and one of locomotives developed a problem and stopped running. What would happen? Well, what would happen is the train would lose half of its power and would be severely under-powered. This train would most likely not be able to continue onward. But if we had three CW60AC's on that same train and one of the units failed, then that train would only lose one-thrid of its power and most likely it would be able to continue on.

For fast trains, like "hot" intermodals, having high horsepower locomotives is good because you need alot of horsepower to pull at speed. High priority trains are usually over-powered on purpose because if one unit goes down it wont effect the train so much. Lowerer priority trains get around 1-3 HP per ton while high priority trains get 4-6 HP per ton.

Just my two cents. :wink:

oltmannd
09-18-2003, 02:02 PM
But do railroads really need a 6000 HP locomotive? Say if there were two CW60AC's on a 16,000 ton coal train and one of locomotives developed a problem and stopped running. What would happen? Well, what would happen is the train would lose half of its power and would be severely under-powered. This train would most likely not be able to continue onward. But if we had three CW60AC's on that same train and one of the units failed, then that train would only lose one-thrid of its power and most likely it would be able to continue on.

For fast trains, like "hot" intermodals, having high horsepower locomotives is good because you need alot of horsepower to pull at speed. High priority trains are usually over-powered on purpose because if one unit goes down it wont effect the train so much. Lowerer priority trains get around 1-3 HP per ton while high priority trains get 4-6 HP per ton.

Just my two cents. :wink:

Well, in the old days, merch trains would get 2 hp/ton and intermodal 4 or more. On Conrail (and NS now) the practice is about 1 HP/ton on merchandise and 1.75-2.25 on intermodal. This is sufficient for schedule keeping. Any higher and you are wasting a ton of fuel.

No RR today can afford to add a "protection" locomotive to a train in case one quits enroute. Conrail stopped doing it in the mid-80s. If you need 12000 HP for a 6000 ton stack train you could use 3 4000 HP units or 2 6000 HP units. All other things being equal, you save quite a bit have 2 6000 HP locos rather than 3 4000s (periodic inspections, idle fuel, overhaul cost, wheels, brakeshoes, etc). It is true that if you lost one unit while underway, you could limp home a bit faster on 8000 HP than 6000 HP.

Another way to look at it is that you could operate any merchandise train on the RR with a pair of 6000 HP AC units without ever having to worry if today's train's tonnage required a third unit. This would provide for a "universal" consist. I think this is what the UP and CSX (and Conrail with the 80 MACs) were looking for when they purchased some. The problem so far has been that "all things aren't equal". The diesel engines in both the EMD and GE units were far from ready for prime time (which shouldn't have been a surprise to anybody!)

-Don