628's and modern GE's

[omax]

Have you ever noticed that GE's AC4400CW's/dash-9's, and GEVO's share some similarities in design; and systems layout, with the 6 axle Alco 628.

Basically, the 628's long hood has a rear top mounted radiator section, like the GE's, that has a small amount of over-hang, to it. The 628's dynamic brake is located forward, as are the GE units.

I know these similarities are minimal, but you can see where GE appears to have gotten their design influences from. Remember, Alco, and GE where at one time partners, in the locomotive manufacturing business.

Just something I have noticed, from time to time.


Rick

 

[omax]

Actually it's pretty hard not to notice... as I currently have a Conrail C628 sitting on a siding, on my O gauge layout; and on a nearby parallel siding sits the the GE Demo 2005 ES44AC, partnered with a UP AC4400CW.

Basically, the Alco, and the GE's, have an obvious connection, re: the layout of the major components.

EMD's locomotives don't have that same connection. The Alco has low mounted
air vents, at the rear of the long hood, though. That bears some resemblance to EMD's tunnel motor units.


Rick

 

[Triplex]

Which, I guess, explains why SP only needed special "tunnel motors" from EMD. Standard GE and Alco models presumably had less trouble.

 

[omax]

Triplex,

Back in 1973, I spent some time up in Revelstoke B.C. A buddy of mine got hired on for the summer as a CP brakeman. I was too young by a few months to get hired on as a brakeman, but I went up there for some adventure.

I regularly saw CP's EMD units coming, and going through the tunnels up there; and that never seemed to be a problem for those EMD units. They weren't tunnel motors, either.

Back to the Alcos:

I remember seeing some of those wide cabbed BCR C628's/or 630's, whatever, years ago; and I barely paid attention to them. I'd love to see one motoring nowadays, though. I'd like to see, and hear one running full out... might be nice.


Rick

 

[5thGenRR]

Which, I guess, explains why SP only needed special "tunnel motors" from EMD. Standard GE and Alco models presumably had less trouble.

GE's were never taken through the tunnels with SP. Out here GE was like an Alien. They would choke and die in the tunnels.

 

[KevinD]

I regularly saw CP's EMD units coming, and going through the tunnels up there; and that never seemed to be a problem for those EMD units. They weren't tunnel motors, either.

But then again, the climate of Revelstoke BC ls alot cooler than Tehachapi CA.

The uprated nature of the SD75M over the SD70M was pushing the cooling capacity of EMD's radiator design. ATSF had all kinds of overheating problems with theirs, but CN not so much. ATSF assigned theirs to the transcon, and ran theirs across the heat of the Mojave, so troubles with cooling quickly surfaced. When BNSF came along and the SD75s got reassigned to Havre, Dilworth, and other assignment bases along the ex-GN Hi Line, the problems subsided a bit. They are still pretty much assigned there today.

 

[omax]

Kevin,

An interesting point you bring up re: California's higher temperatures.

I personally don't think outside air temperature has much bearing on the environment inside a long railroad tunnel. The Connaught tunnel is approximately 5 miles long. I think the air inside a tunnel like the Connaught tunnel, would be cooler than the outside air temperature. I think the tunnel itself, would act like a giant insulator, probably keeping the internal temperature of the tunnel, at a fairly constant temperature, year-round.

To me, the real issue is the confined finite space of the tunnel. As I'm sure you are aware, hot/warm air rises; and having hard-working locomotives inside a tight enclosed space, emitting dirty super-heated air, that gets trapped by the tunnels ceiling... that's where the problem lies.

If you factor in numerous hard-working units in a consist... then the problem is compounded. Tunnels are usually located in geographic locations that place greater demands on the motive power.

The exhaust from those older units was very dirty, and quickly covered everything in the vicinity with a layer of soot. This soot would cause problems for a locomotive, when it was aspirated by the unit. Add the super-heated air factor into the equation, and that is when operating problems can; and do occur.

Operating locomotives in a super-heated dirty environment, within a confined space, is where the problem lies.

Note: some tunnels have large fans placed throughout, to exhaust out the unwanted problem air; and pull in clean fresh air.

Rick

 

[5thGenRR]

Kevin,
To me, the real issue is the confined finite space of the tunnel. As I'm sure you are aware, hot/warm air rises; and having hard-working locomotives inside a tight enclosed space, emitting dirty super-heated air, that gets trapped by the tunnels ceiling... that's where the problem lies.

If you factor in numerous hard-working units in a consist... then the problem is compounded. Tunnels are usually located in geographic locations that place greater demands on the motive power.

The exhaust from those older units was very dirty, and quickly covered everything in the vicinity with a layer of soot. This soot would cause problems for a locomotive, when it was aspirated by the unit. Add the super-heated air factor into the equation, and that is when operating problems can; and do occur.

Operating locomotives in a super-heated dirty environment, within a confined space, is where the problem lies.

Rick

Rick,
You hit the nail on the head. This is not only your oppinion but scientific fact. All of our Turbo'd GE's and EMD's have intercooler's (EMD calls them Aftercooler) to keep the air cool and dense. When GE came out with the ES4400 they did somthing that is over kill for most situatuions but is needed for tunnel opperations. They have what they call air to air as well as air to water intercooling. This form of temperature control can bring the intake charge air to an insanely low temp even in a tunnel. I have it written down somewhere in one of my training manuals and will try to dig it up.

 

[Cliffs]

Is this the Air-To-Air heat exchanger for the charge air?

Its the only time I have seen the air passages extending above the roofline.

 

[omax]

Hi Chris,

I enjoyed reading/seeing your posts... they add to our understanding of railroading.

Thanks for sharing your knowledge.


Rick

 

[5thGenRR]

Rick,
You may notice that in the last couple weeks I have posted a lot. First is because I have had time and this Forum is new to me. Although I am on a lot of forums mostly related to Classic Cars, Trucks and Muscle Cars. This forum is one I feel like I can be apart of not just sit on the sidelines. The second is that I know from reading as well as talking to people that I meet in everyday life that there are lots of questions about railroading. Most people have a huge misunderstanding of how locomotives/trains & railroads run and operate. I by no means know everything but in my line of work I am the person people go to to seek info from. Some times it has to do with how other parts of the system operate since most of my heritage is TE&Y and Clerical. Also I dig this realm of our society and Americana. I'm constaintly trying to figure out how they run railroads and how other departments work.

If I ever seem too wordy or overbearing let me know. Don't be afraid to hurt my feeling. There is only one left. You have to be thick skinned to work at the railroad.

 

[omax]

Chris,

It's been enjoyable, and informative conversing with you, here; and that's why I come to this forum.

Take care.


Rick

 

[Cliffs]

Thanks for the info about the Air-To-Air heat exchanger!

This is great info and one of the reasons why this forum is enjoyable.

 

[Abilene Ks Railfan]

Are the GE's better suited for pulling heavy unit trains? Of the coal,and grain trains I see, the consists are 99% all GE

 

[5thGenRR]

I don't know if they are better than EMD in that way. From the feedback we get from TE&Y they have an excelent tractive effort.

 

[Abilene Ks Railfan]

Thanks again for the info, I do enjoy your posts, I've always admired the workers who keep these beasts going strong. I take part more here Myself,than the 2 car forums I belong to