Do any American railcars have just two axles?

[Robert Gift]

Why do/did so many European railcars have two axles?
Lower weight?
Thank you.

 

[kenw]

lower weight, sharper curves.

A few North American freight cars have have single axle trucks, in particular an articulated (iirc) COFC/TOFC (Container or Trailer On Flat Car) railcar of a few years back. Containers and trailers are normally very light and the reduced rolling friction of a single axle helps reduce fuel consumption. Haven't seen any in many years tho so I don't know if they are still around.

 

[Robert Gift]

lower weight, sharper curves.

A few North American freight cars have have single axle trucks, in particular an articulated (iirc) COFC/TOFC (Container or Trailer On Flat Car) railcar of a few years back. Containers and trailers are normally very light and the reduced rolling friction of a single axle helps reduce fuel consumption. Haven't seen any in many years tho so I don't know if they are still around.

Thanks, Ken.
Are they fixed? (Do not swivel.)
Slightly higherisk of derailing?

 

[LoganTrackdog]

Bobber caboose comes to mind.

 

[Sean R Das]

All I know is that bobber cabooses and some intermodal equipment have only 2 axles.

In general, most British/European rolling stock has a shorter wheelbase than North American rolling stock. The longer the wheelbase, the more axles are needed to support it.

 

[Rader Sidetrack]

Here is a two axle scale test car:

http://www.railpictures.net/viewphoto.php?id=223772

 

[kenw]

.... The longer the wheelbase, the more axles are needed to support it.

not exactly. More axles support more load. That's why heavy duty flatcars have so many: to support so much weight.

 

[Bob]

The Talgo essentially only has two axles. It's an articulated train, with each segment supported by a single axle at each end, or at least so it appears.

In actuality, the train uses a split axle system, so each wheel has it's own axle. But for the sake of this discussion, it's functionally the same as a single axle.

 

[weekendrailroader]

Lots of smaller American MoW equipment had two axles as well. Tie carts, tie cranes, ballast spreaders, spike zappers, etc.

Correct me if I'm wrong, but I thought that American equipment evolved into having two trucks under car because, in the early stages of the railroad, American tracks were quite rough compared to Britain's tracks. I always hear about how crews hated bobber cabooses because they gave such a rough ride (thus the term "bobber").

 

[Tacoma Tom]

Other than the weight scale test cars then only ones I ever remember seeing is those flatcars that carried trailers. Those seemed to be short lived and ended by the early 1990's. Single axle flat cars were so lightweight they tended to derail at higher speeds when crossing switches due to the bouncing. I remember reading a story about how one of those cars derailed,was bouncing on the rocks and ties for about a mile,then it hit a switch at the frog and re-railed itself back onto the tracks.

Lightweight cars also create problems when traveling. Certain empty cars like flat cars and empty container cars can not be placed in the middle of a train if there is a certain amount of tonnage trailing it I (believe it is 4500 trailing tons). It can buckle and derail when braking downhill due to all the weight pushing against it. I don't believe the European railroads run anywhere close to the length and tonnage we do on our average trains.

While we are on the subject...Anyone remember when they were hauling truck trailers by just placing a set of wheels under the trailer? Sounds unbelievable but they were depending on the aluminum frames of the trailer to push and pull the trains. Not sure how long those lasted or what became of it and would enjoy hearing any info.

 

[Rader Sidetrack]

While we are on the subject...Anyone remember when they were hauling truck trailers by just placing a set of wheels under the trailer? Sounds unbelievable but they were depending on the aluminum frames of the trailer to push and pull the trains. Not sure how long those lasted or what became of it and would enjoy hearing any info.

Norfolk Southern has a subsidiary called Triple Crown Services that still operates roadrailer trains today. These are essentially truck trailers joined together by rolling a rail wheelset under the the rear of the trailer.

Some more photos of the equipment here:

http://www.triplecrownsvc.com/Bimodal.html

 

[Tacoma Tom]

Norfolk Southern has a subsidiary called Triple Crown Services that still operates roadrailer trains today. These are essentially truck trailers joined together by rolling a rail wheelset under the the rear of the trailer.

Some more photos of the equipment here:

http://www.triplecrownsvc.com/Bimodal.html

I had no idea they were still using those. I will have to make a visit out East to check that out. It's hard to believe those were ever a success. It would seem they wouldn't stay on the rails especially if they were running in high wind where those trailers would blow over easy. Apparently they are successful as I have never read about any incidents yet.

 

[kenw]

It would seem they wouldn't stay on the rails especially if they were running in high wind where those trailers would blow over easy. Apparently they are successful as I have never read about any incidents yet.

actually they have a lower center of gravity (notice that the are much closer to the tracks) so they in theory have less chance of blowover. The biggest issue is that the trailers themselves must have very heavy duty frames to provide drawbar strength, and heavy duty frames hurt fuel mileage when used as a truck trailer.

 

[NM_RailNut]

Lots of smaller American MoW equipment had two axles as well. Tie carts, tie cranes, ballast spreaders, spike zappers, etc.

Correct me if I'm wrong, but I thought that American equipment evolved into having two trucks under car because, in the early stages of the railroad, American tracks were quite rough compared to Britain's tracks. I always hear about how crews hated bobber cabooses because they gave such a rough ride (thus the term "bobber").

They weren't just rough, but also lightly built with lots of curves. Early American railroads didn't have the same level of financial backing that their British and European counterparts had, which meant that the track and bridges were often lightly built and followed the lay of the land with lots of curves and very few cuts, fills, or tunnels. That sort of construction pretty much meant that freight and passenger cars with two or even three axle trucks were sorely needed if the railroads in question expected to stay in business.

British and many European railroads did have decent financial backing and had well-engineered routes with very substantial track and bridges that could handle heavier loads and axle loadings than their American brethren, and also had much gentler curves since they could afford to use cuts and fills much more often (tunnels were still avoided when possible though, as tunneling was still done largely by hand); single-axle cars worked just fine for these railroads.

 

[Jon Bentz]

Here's shot of a couple of Portec 4 Runners from the late 80's. These were the only ones I ever saw that we're painted for TTX.

 

[Robert Gift]

Here's shot of a couple of Portec 4 Runners from the late 80's. These were the only ones I ever saw that we're painted for TTX.

Were those cars E X P A N D A B L E ?

 

[NM_RailNut]

Nope. The 4 Runners were introduced in the early '80s when 40' trailers and containers were the largest in use and had largely fallen out of use by the time longer trailers and containers came into being; that and tracking problems at high speeds (which were even worse when empty and was the main reason why they fell out of use in the first place) are why you don't see them in use much (if at all) today.

 

[728 Cable Donkey]

I had no idea they were still using those. I will have to make a visit out East to check that out. It's hard to believe those were ever a success. It would seem they wouldn't stay on the rails especially if they were running in high wind where those trailers would blow over easy. Apparently they are successful as I have never read about any incidents yet.

I just returned from 2 months in Ohio working on a movie and was able to spend a day at both Fostoria and Berea, as well as Cleveland were we stayed. I saw many roadrailers. Looks like a smart way to move trailers and the train seemed very stable.