Aluminum Freight Cars

[mvlandsw]

Since aluminum coal cars have become economical and popular why are there not more cars of other types be built of aluminum?

[CShaveRR]

There were (and may still be a few) tank cars with aluminum tanks, both pressure and non-pressure. They were probably used for certain acids where chemical reaction with steel presented more difficulty. If they weren't welded, as you suggest, Mark, that's probably a good reason they haven't been built recently. Back in the days when tank cars had a raft of mechanical designations, TR and TRI were aluminum non-pressure cars and TPA and TPAI were the pressure tanks (the "I" standing for insulated, of course). I think that if you look through the list of Car Type Codes for tank cars, you'll still find codes assigned to aluminum tanks (though the cars that are actually given those codes may no longer be around.

[dehusman]

The major benefit of an aluminum car is lower tare weight. Since the amount that the car and its lading can be is fixed, the less weight in the car, the more weight in commodity can be carried. This only is important in commodities that are bulk. Coal being the major one. Boxcars are not normally loadded to full capacity so the advantage of alumium is lost. Tank cars are cubic capacity and so aren't really a problem.

Dave H.

[Junctionfan]

Are you sure the insides of them were not lined with aluminum? Most tank cars that I know of are steel with various inner layers such as glass, rubber, stainless steel, plastic etc.

[Anonymous]

I had no idea they made cars of AL. What railway owns these aluminun cars

[Anonymous]

Johnstown America is a major manufacturer of Aluminum coal hoppers and one of thier assembly plants is located about 1 mile north of my home terminal in Danville, IL. They turn out about 20-25 cars a day!!! And as Mark has said many of the cars #'s are BNSF or private utility companies.
I also noticed one aluminum coal hopper has been set out at one of our rip tracks a long time, it has a tear in the bottom portion of the car and coal is just waiting to pour out. To me it looks like the coal hopper was overloaded and the integrity of the car was compromised by the extra weight. It is hard to fix the car because the weight of the coal pushing the car body down makes the gap too wide to weld, what to do with all that coal??? It's definitely not able to be taken over the road.

[Junctionfan]

CN also owns those Trinity 48 foot "aluminators".

Other aluminum cars are those new autoracks built by Johnston America bought by First Union Rail and leased by CN.

[Dough]

QUOTE: Originally posted by n_stephenson

... what to do with all that coal??? It's definitely not able to be taken over the road.

My guess is that they will bring in a backhoe or a track hoe to dig most of it out and put it in another hopper (or trucks). Have you ever seen a Herzog attachment for backhoes that allows them to ride on top of gondolas and hoppers?

I have also seen CSX use trackhoes to empty ties and ballast. Watching those unmodified pieces of equipment navigate from one car to the next is quite scarry.

Also I have seen giant vacume trucks used to clean up grain spills where covered hoppers busted.

[Overmod]

It's not particularly difficult to weld aluminum, even in heavy sections, with modern methods (e.g., the inert-gas blanket methods). Traditionally it was a bit more difficult to 'prove' the weld integrity, but there are good methods (e.g. ultrasound) to do that, too.

Principal reasons are as stated: High initial cost of capital vs. return, and lack of ROI in general service, and greater susceptibility to breakage and damage. Something known, but not explicitly mentioned, is that aluminum is more prone to *fatigue* damage, both in typical sections and in sheet form. Methods of stress-relieving built-up welded structures can be a bit arcane for traditional car makers.

Another point is that traditional 'low-tare-weight' aluminum structures are largely stiffened by monocoque-type construction -- think of airplane fuselages. A coal gon, especially one with rotary couplers that doesn't need bottom doors, can be very effectively stiffened via this kind of construction. A boxcar, much less so.

With regard to tank cars -- what was said is that a 'full' weight load for most tank-car services doesn't require a large enclosed volume or large car size, and therefore the tare-weight benefits are proportionally less. Aluminum can also be EXTREMELY reactive (compared to steel) when accidentally exposed to many of the chemicals carried this way, and its lower net strength means that corrosion may compromise integrity more dramatically than a 'steel' alternative. The coefficient of expansion for aluminum is much greater, which makes the design of effective liners much more difficult.

[Dough]

Are we talking about an aluminum car not being able to support an excavator?. I'm not disagreeing with that, especially with a damaged car, but people often do run excavators (trackhoes) over hoppers. Check out the link below, and scroll down to the full size ones on top. They even have the vacuum:
http://southern.railfan.net/coal/article.html

As far as the reach for a backhoe, check out this link to Herzog's Cartopper. (For those that don't know there is a set of pictures in a past Trains that explains how it gets on and off of the cars!) Hey and there is even a movie on the website now! Notice the unloading of ties from hoppers just as CSX does in the movie.
http://www.herzogcompanies.com/rrservices/cartopper.php

I have also seen CSX MoW use a small CAT excavator to both empty ballast and to empty ties. When I’m home next I’ll check the model number for you. They have modified a ramp car to drive it up to gondola height. CSX also uses a bunch of old 70ton hoppers for tie loading only. Now how they unload these I have never seen, but I would bet it is with that same little excavator. I don't know how it manages to negotiate the extra height, or out of an empty hopper, but these guys can do some crazy things with that little tractor.

Edit: One more thing. I have never seen the Cartoppers use the wihch. Every time I watch them they move by grappling on with the arm and pulling or pushing along. Maybe it is harder with the bucket?

[Overmod]

The solution we developed years ago combined aspects of the 'cartopper', the backhoe, and the Schwing concrete pump. Basically, the part of the system that runs along the top sills of the cars is light, basically nothing more than a roadable chassis with lifting hardpoints and some means of propelling itself along the sill and 'jumping' between cars when necessary. This carries the hoses and lines for a vacuum system that has heads appropriate for picking up, 'attriting', slurrying, etc. cargo to be removed from an integral-train car or trough car. The head also has directional capability and some independent mobility so that the vacuum's boom doesn't have to be heavy to steer the hose. It's also comparatively easy to use a rubber bucket conveyor to do lifting once the powered head has loosened the material and fed it appropriately; this isn't something so heavy as to cause problems for sills strong enough to prevent hoop deformation in loaded hoppers, for example.

All the main power, vacuum separation chambers, post-handling, etc. sit on the ground, away from food-grade material, chemicals, explosive vapors or dusts, etc. etc. etc. It's relatively trivial and cost-effective to have different hoses and head liners for different kinds of product, rather than requiring completely different systems for different classes of material.

We also developed systems that used straddle-loading and "half-straddling" frames, and adapted scissors-lift platforms, to bring handling equipment on roadable (or, as we put it, "off-roadable") chassis up to, and over, railcars that would otherwise be ill-suited to trackside loading or unloading -- for example, covered hoppers with only sealable ports or hatches for roof loading.

By analogy with suspensions -- you want to keep unsprung weight to a minimum, and that means that whatever actually touches or sits on the cars wants to be light and agile. It's not as directly cost-effective, of course, as Herzog's "hi-rail backhoe" conversion, but that was intended primarily for ballast service out of Herzog's gondola cars, where the material, its characteristics, and the lift height are all well-established and within the capability of the equipment.

Yeah, there's a point about using the CarTopper for unloading unit coal trains, though. You'd need something considerably larger AND faster... and moreover that couldn't inadvertently scar up or punch through the soft aluminum sheets while trying to grab or scoop part of the load. I wouldn't want to be the investment banker who loaned venture capital to an outfit that intended to try that in a routine high volume everyday operation! (Not that it can't be technically done... just that you'd be paying more than established alternatives would cost to be able to do it 'right' -- or even at all with any consistency.)

[Dough]

Ok, I don't doubt that it wouldn't be able to ride on top of an aluminum car. I actually know nothing about them at all so I don't doubt it a bit. And if it has to be on the ground then, yes, you are going to need an excavator with a very long boom unless you plan to go the vacuming route.

I was actually supprised to see that outfit in Augusta that uses the trachoes to empty coal. I'm going to have to travel over there one day as it is only a few hours drive from here. I guess that they aren't going to be getting any aluminum hoppers in anytime soon...[;)]

I'm also still curious as to how CSX empties those tie only hoppers. I can't imagine the excavator being able to get out of one when it is empty like they can with a gondola. And unlike the ones at Augusta it has NO modifications. If I haven't mentioned before it is very scarry to watch it go from one car to another.

[Overmod]

Some hints here, possibly: Look carefully at the pix of that NS operation.

The "hoppers" are labeled Top Gon, which tells us what we need to know about braces or intended service, I think. Note that the smaller excavator IS specially built to run along the top sills (and between cars) on much the same principle as the Herzog ballast backhoe... it looks as if there are special extenders and perhaps custom grouser pads on the track units, to match the extended 'gauge' of the top sills on the Top Gon cars.

I also think, both from the position of the larger crawler and from the slant of those 'side rail' units in the end-on picture, that you're looking at what are in essence 'clamp-on' ramps that form a platform beneath the crawler tracks. My assumption in operations would be as follows:

1) Crawler is positioned at the end of the car, or bridging the endsills of two adjacent cars (can't say how it gets there)

2) Clamp-on ramps are positioned near that end of the car to be unloaded, so that as the crawler moves forward (at least partly on the coal in the car) the tracks will come up on the inside of the clamp ramps, which then take up the weight of the crawler, stabilize it level fore-and-aft against dip and laterally against swing, and allow the coal to fall away as the car is scooped empty.

3) When done, the crawler backs off the ramps, which are then pulled off.

You wouldn't do this with aluminum cars! There would be a substantial lateral force on the upper sheets and the top sills, bending inward -- presumably the modifications that make a Top Gon are capable of taking this in stride. However, I see little reason why an aluminum-framed hopper couldn't be equipped with cross braces or hard points that would allow use of these ramps... or why the ramps themselves couldn't be fitted with cross-bracing to handle the 'cantilever' loads, for example provided as extendable tubes or sliding formed-section rails. I also see little reason why the excavator itself can't be designed to pick & place the ramps (perhaps using a winch to bring them up from trackside to rough position inside the car if the excavator boom isn't capable of the necessary excursion).

You'd need multiple ramps to negotiate empty places, or to get down the length of a loaded car to start unloading if you didn't want to run on the coal already there. But that's no more difficult in theory than operating one of those military railroads with panel track (like the one for which the first Mallet was designed, IIRC)

[Dough]

QUOTE: Originally posted by M.W. Hemphill

The excavator sits IN the hopper? Not on the topsills? And it's a hopper, not a gon? Most hoppers, as well as coal gons, have cross-braces inside (they show in the photos you linked), and you'd get tangled up in those. I'm not doubting what you saw, I'm just baffled.

You aren't the only one who is baffled! I don't know for sure how they empty those hoppers. That's why I'm asking. I really wi***hat I could scan those pictures up for you. I am really kicking myself for not leaving them online. It does not ride on the sills at all. It is a small CAT excavator that actually has one of those small blades on the front. I have seen it in gondolas plenty of times. However I have not seen it on the hoppers.

CSX has taken a bunch of old 70 ton hoppers (B&O, C&O, etc) and stenciled "Tie Loading Only" on the side. I actually wondered how they put ties in there with the bracing. Now these were in town at the same time as the gondolas and the only thing unloading ties was that excavator. In fact there were many more hoppers than gondolas. I don't know that it gets in there at all. Maybe it leaves enough ties to get to the next car and finishes unloading from there. I just don't know, and that is why I am curious. It may take a few weeks, but put the pics of the ramp car back online eventually.

[Dough]

Edit: Never mind the website below explains it. Now what they use to load them I don't know. And it still seems like it would be a mess trying to get them untangled from the bracing...

http://www.hubhobbyshop.com/mow3.htm

Ok, now this is interesting. Go to the bottom of page four. Take a look at that ramp car. Unlike the one I saw it is a gondola ramping up to the height of a hopper. And it is a much bigger tractor. Now I'm really confused! [xx(]

http://www.hubhobbyshop.com/mow4.htm

Ok last edit I swear. I see that it becomes level at the top. Maybe the excavator sits there and unloads it? Of course then you would have to constantly switch cars in and out. And the flatcar ramp at gondola height that I saw also had a level portion so I just don't know...

[jeaton]

Back to getting the coal out. I have had it done. Get a crane with a clam shovel, they arere around even if not used too much, and with a little care dip most of the coal out. Couple of guys with coal shovels can load the clam when it is down to cleanout. (Remember, coal burns, not a good idea to have a small pile in the welding area.)

Jay

[Dough]

Oh man that site is great. On page five they have the tie loading only gondolas. I always wondered what those NS units were made out of!

Anyway this should clear it all up. From the photographer himself:

QUOTE: Hi----I went back and looked at the CAT pic again to be sure I remembered it correctly, and now I recall what I was told about it. This cat had a grabber, not a bucket, and was used to pick up discarded crossties. CSX was doing track projects in the area of Gentilly Yard (New Orleans East), and expanding the intermodal ('tote') yard there, and since the yard was built on a drained bayou, lots of crossties needed to be replaced. The last hopper shown in http://www.hubhobbyshop.com/mow3.htm , the former L&N hopper, was typical of the cars used to carry away the replaced ties. I was told by the MOW crew that as the hopper was filled up with the ties by the CAT, the CAT could crawl over the top of them and move to the next car by walking atop the first, and so on. I am skeptical of that, but the crew told me that with a straight face, so who knows? I do know that many, many loads of bad ties were carried away by these cars over a 6-month period. I also was told that when they reached the recycle site, some of them were still good in the middle and could have the ends cut off and be reused (if they were still long enough), and others cleaned up and sold to garden centers and such. Why throw it away if you can get money for it?

Patrick

[Dough]

That makes sense about the removal of the bracing. I guess that we have strayed a bit from the aluminum car start, but I learned a bunch about MoW operations from this discussion and my research today. Good conversation![;)]

[Overmod]

I'm trying to find information on the Top Gon rebuilding program, but Ms. Google is distressingly short on useful information from those in the know. I have found two useful links with pieces of information in them...

http://www.krunk.org/~joeshaw/pics/ns/coal-gon/g89r.shtml
http://www.krunk.org/~joeshaw/pics/ns/coal-gon/g101r.shtml

two different classes with some descriptive captioning. If I understand this correctly, the interior braces have been removed and external bracing or a stronger underframe substituted. I've found numerous links describing trains with these cars, but none that specifically note the unloading procedures in any detail, so I don't know if there is any remaining structure to tie the sidewalls together in ways that interfere with 'top unloading'.

[Dough]

Hey Overmod, be careful, you could spend all day researching this stuff. I would know!!!

What specificially are you looking for? The picture of that coal unloading facility in Augusta has an interior shot that shows the bracing. Apparently they only dig it out utill they get to the bottom. Then they use that smaller excavator to vacum the remainder. Do you know if the ones in the link are part of the rebuild or not?

[pat390]

Aluminum is more expensive but it is better because it weighs less whereas steel is heavey but CHEAP

[Dough]

With regards to the orginial question. NS apparently has 400 aluminum hoppers. Go to the coal section:

http://www.nscorp.com/nscorp/index.jsp

[Junctionfan]

I wonder if someone plans to make a railcar out of titanium.

[Overmod]

No particular advantage in making railcars of titanium. Don't have to run at hypersonic speeds, like Boeing's 2707, don't have to evade MADs like an Akula, DO have to be repairable with cheap materials by people without skill welding pyrophoric material...

Last I looked, there wasn't that much of a good scrap market (outside Vladivostok) and the cost of producing titanium metal (and, more important, procuring formed section and sheet) was still... ah, rather high. I'd expect to see titanium automobiles first... and I'm not exactly holding my breath.