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- Newsgroups: rec.railroad
- Path: sparky!uunet!destroyer!gatech!rpi!usenet.rpi.edu!pratta
- From: pratta@rpi.edu (Anthony Edward Prattico)
- Subject: Re: Genesee & Wyoming Now in Oregon
- In-Reply-To: 195ochs@gw.wmich.edu's message of 28 Jan 93 00:22:33 EST
- Message-ID: <PRATTA.93Jan28113223@rebecca.rpi.edu>
- Nntp-Posting-Host: rebecca.its.rpi.edu
- Organization: Rensselaer Polytechnic Institute
- References: <1993Jan18.201448.12869@hpmcaa.mcm.hp.com> <122200199@hpfcso.FC.HP.COM>
- <1993Jan28.002233.7516@gw.wmich.edu>
- Date: Thu, 28 Jan 1993 16:32:23 GMT
- Lines: 43
-
- In article <1993Jan28.002233.7516@gw.wmich.edu> 195ochs@gw.wmich.edu writes:
-
- >SD's are mostly used for more traction, since they have more traction
- >motors. GP's are lighter and are also typically used for highspeed trains
- >(intermodal, etc)
- >Here's some typical weights of locos from Chessie System and CSX
- >(sort of an approximate, since different class engines weighed differently)
- >
- >GP 7/9 250,000
- >SD 7/9 370,000 (these were ballasted to make them slightly heavier)
- >GP35 260,000
- >SD35 390,000
- >GP38 270,000
- >SD38 380,000
- >GP40 275,000
- >SD40 390,000
- >
- >and also some GE's to compare:
- >U30B 277,000
- >U30C 377,000
- >B30-7 277,000
- >C30-7 385,000 and 411,500 (they have 2 different weights listed)
- >B40-8 288,000
- >C40-8 395,000
- >
- >So you can clearly see that there is typically 120,000-140,000
- >pounds between a B and a C trucked engine. This is very crucial on branch
- >lines. Most branchlines will be restricted to a GP30, GP35 or GP38 or GP40
- >or GP7/9 on some RR's (CSX doesn't have any GP7/9's left, they usually use
- >GP30,GP38.GP39,GP40 GP16 (rebuilt GP7/9's) and U18B,U36B, and B30-7's
- >on the locals in Michigan. Mostly GP30's and GP40's since they have scads
- >of GP40's (and GP40-2's)
-
- True, but the real limit is the weight PER AXLE. Of all the engines above, the
- weight per axle of the six axle engines is EQUAL TO OR LESS THAN that of the
- four axle units. Many of the problems with branchlines stems from the sharper
- curves that cause problems with the six axle units, which have a much larger
- minimum radius. I don't know about the particular trackage in question, but I'd
- assume this is more likely the case, giving the lower axle loads of the six
- axle units. In your example of locals, I bet that there are many industries
- sharp curved sidings to be served, which would demand a four axle unit.
-
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-