Unloading Coal

[Bob-Fryml]

Air to operate the gates comes from the trainline.

No, no, no. The train line is the same as the brake pipe. Using brake pipe air to charge the cylinders that operate the dump doors would cause the train brakes to apply. Besides, I very much doubt that the Federal Railroad Administration would ever allow such a practice.

Actually, air dump coal hoppers have two air hoses: one for the brake pipe and a second one that charges the dump door system. The source of air for the latter is the main reservoir hose on the locomotive. This hose is part of the m.u. hose system that is coupled among the units comprising a locomotive consist.

The trailing end of the trailing unit in a locomotive consist has two main reservoir hoses available, one on each side. The freight-car-dump-door-system-hose is coupled to one of the main reservoir hoses on the locomotive. When the anglecock is opened on the locomotive main reservoir hose, compressed air shoots into the coal cars, and when sufficient pressure is reached throughout the train, the cars are then ready to be dumped.

Main reservoir hoses, when opened, typically carry between 120 and 130 psi.

Incidently, as a safety measure to prevent any unwanted dump door activity, the freight-car-dump-door-system-hose and the main reservoir hose on the locomotive usually are disconnected from each other as the equipment moves loaded (or empty) between the mine and the consignee.

[Anonymous]

OK, I’m here, finally.

Mr. Hadid, there are plenty of rapid-discharge hoppers that are also equipped with rotary-coupler ends. That way they can be unloaded at either type of facility commonly seen at power plants.

Rapid-discharge (using the term generically–it used to be Ortner’s trademark) cars use air to operate the gates, which open more widely than those on conventional hoppers. In fact, it’s like the entire bottom falling out. The gates are actuated by a shoe on the side of the car, which is triggered electronically. Air to operate the gates comes from the trainline. I believe these trains have to sit somewhere, change hoses, and charge up the discharge system a short time before going through the plant.

To the many who asked, Bethgons and similar cars are, as the name implies, gondolas. No discharge outlets; dump on a rotary dumper only.

And as for the improperly-oriented rotary couplers, we’ve had a thread on this before. They may pose a bit of an operational problem when two rotary couplers are coupled to each other–the whole coupling may shift and cause some undue binding. However, a dumper that can handle two cars at once will have no problem dumping cars regardless of their orientation. All you have to do is be sure that the coupling without any rotary couplers is in the middle.

Thanks for all the answers. I’ve seen the rapid discharge types and noticed the extra air hose. These were apparently Bethgons, based on a picture I found on the picture site, with the rounded ‘bathtub’ bottoms and I assume the extra hose for compatibility. It sounds like having the ends mixed-up would just slow down the dumping process on a 2 car dumper. Do they ever shove empties over a hump to get 2 sets oriented the same way? There probably weren’t more than 5 or 6 in a row on this train. I’m guessing this train gets broken up and sent to multiple power plants

[beaulieu]

[quote user=“up829”]

OK, I’m here, finally.

Mr. Hadid, there are plenty of rapid-discharge hoppers that are also equipped with rotary-coupler ends. That way they can be unloaded at either type of facility commonly seen at power plants.

Rapid-discharge (using the term generically–it used to be Ortner’s trademark) cars use air to operate the gates, which open more widely than those on conventional hoppers. In fact, it’s like the entire bottom falling out. The gates are actuated by a shoe on the side of the car, which is triggered electronically. Air to operate the gates comes from the trainline. I believe these trains have to sit somewhere, change hoses, and charge up the discharge system a short time before going through the plant.

To the many who asked, Bethgons and similar cars are, as the name implies, gondolas. No discharge outlets; dump on a rotary dumper only.

And as for the improperly-oriented rotary couplers, we’ve had a thread on this before. They may pose a bit of an operational problem when two rotary couplers are coupled to each other–the whole coupling may shift and cause some undue binding. However, a dumper that can handle two cars at once will have no problem dumping cars regardless of their orientation. All you have to do is be sure that the coupling without any rotary couplers is in the middle.

Thanks for all the answers. I’ve seen the rapid discharge types and noticed the extra air hose. These were apparently Bethgons, based on a picture I found on the picture site, with the rounded ‘bathtub’ bottoms and I assume the extra hose for compatibility. It sounds like having the ends mixed-up would just slow down the dumping process on a 2 car dumper. Do they ever shove empties over a hump to get 2 sets oriented the same way? There probably weren’t more than 5 or 6 in a row on this train. I’m guessing this train gets broken up and sent to m

[Northtowne]

Interesting topic and very intelligent and informative responses. Should erase any doubts that this forum might be “dead”.

Northtowne

[jeaton]

CP rail has had rotary dump cars for 30 + plus years.

They run about 110 car unit trains from South eastern BC to The west coast

( Roberts bank ).They can dump 3 cars at a time. Takes about a 8 hour shift.

These unit trains are all robatized.( 1 loco on the head end 1 on the tail end.)It take about 4 days to make the loop and all of these coal sets around 30 sets are serviced at at the Golden BC coal car shop.

That is extremely slow. Figures about 13 minutes per dump cycle. I would expect something on the order of three to five minutes max.

[nanaimo73]

Westshore at Roberts Bank takes two minutes to dump a car. 120 cars in two hours on the double dump track and 120 cars in 4 hours on the single track.

[jeaton]

There is a barge terminal operation on the Tennessee River in western Kentucky that unloads convential hoppers on a bridge dropping coal directly into barges. Cars are spotted two at a time, car knockers open the doors and shakers on each car gets the coal dumped real quick. I have seen 100 car trains-100 tons per car-unloaded in less than an hour.

By the way, a car shaker is a machine that is lowered on to the side wall of a car. An electric motor drives an excentric weight that set up a vibration which is transmitted to the car and lading. The vibration fluidizes the coal which then falls out of the car like, well, a fluid. Any one were hanging on a car during the operation would probably have some teeth shaken out.

[edblysard]

Air activated rapid discharge cars have are charged from the trains main reservoirs, with their own system, complete with on car reservoirs in addition to the brake system.

The hoses between the cars look just like train line hoses, except the glad hand are “backwards” in that you can not attach one to the train line, they do not mate up.

There is a cheater hose that allows the train line from the locomotive to be attached to one end of the cut.

The compressor on the locomotive can charge the system to the required pressure as fast if not faster than it can charge the brake system, then the train line is reconnected back to the brake system.

The discharge system is often not charged up till the train is at the load out for the simple reason running with it charged can cause a mess if one of the activation shoes is un- pinned and then pressed.

The trigger is a shoe, or plate, on a hinge, about sill level, which is held against the side of the car during transit with a simple link pin.

When ready to discharge, the shoe, which is spring loaded, is un pinned, and sticks out from the car about 9 inches to a foot, the air system is then charged …and when the car is dragged past the load out, the shoe or trigger is pressed back by a bumper bar, at the same height as the shoe and about 1/2 a car length long.

Pressing the shoe activates a pneumatic plunger, in turn activating the dump doors…as Carl said, it almost looks like the bottom of the car falls out…by the time it has been dragged a car length, it is empty…the air system on each car hold enough to open and close the doors once…and each car has a small hose, with

[kevarc]

http://www.3dtrains.com/forums/index.php?showtopic=6800&hl=rodemacher

IF the link does not work right, I will try and pull them into a seperate post in my forum there.

The plant is the Rodemacher #2 Electric Plant. The plant is co-owned by Cleco (30%), who operates the plant; City Of Lafayette (50%); and Louisiana Energy and Power Authourity (20%, this is who I worked for). We receive PRB coal from the Black Thunder Mine, delivered by UP. The cars are owned by the three of us. They carry reporting marks of RDX or CLEX. Usual power is three SD’s. The last one I saw had 1 UP and 2 Blue CEFX units. We have a ballon track of the main line north of Alexandria, LA. However the ballon is not quite long enough for the current train when the aluminum cars are used. After the first 20 go throught the rotary dumper they are cut off and tacked to the end. There is also a car repair shop at the plant.

When a train arrives the engines are run through the dumper and the first car is spotted. The engines are put in neutral, they are not used to pull the train while dumping operations are going on. You can see the dog used to advance the train in the picture behind us in the 5thpicture. It is the yellow bar standing vertically. You can see the slot in it, this goes over the coupler and it pushes the train to spot the next car. This view is from inside the dump building. The dog is advanced using a winch. The high rail is to guide the dog trolley. The 4th picture is the inside of the dumper.

[Murphy_Siding]

Kevin: Nice pictures and explantion of things. You say the locomotive is put in neutral, is the cab then empty until the coal is all unloaded?

[Anonymous]

I saw an empty coal train(DETX) the other day with the rotary coupler ends so random, it would have to go over a hump to put things right.

That got me thinking about Rotary coal dumpers. How common are they and what are the pros and cons compared to bottom dumping? How many cars at a time can the biggest ones handle? How long have they been around? How long does it take to unload a coal train?

Are there any that can be seen operating in Northern Illinois, without being a national security risk?

Your original question asked the pros and cons of rotary vs. bottom-dump, presumably for high-tonnage movements moving by unit train. Some of the economic tradeoffs are:

1. Initial cost of equipment. Rapid-discharge cars have, in rough terms, a 10% purchase premium over rotary-dump coal gondoals.

2. Cost of maintenance. Rapid-discharge cars have, roughly, a 5% premium in maintenance costs, primarily for the doors and dumping mechanism. On the other hand rotary-dump cars can be mishandled in a dumper (especially if they are free-runners that go to many dumpers of different designs and operator skills) and can get seriously damaged or fall apart surprisingly quickly.

3. Extra tare weight. This is the Achilles heel of the rapid-discharge car – it has to haul around roughly 5% more metal each trip. That means every round trip made by a 135-car train of 286K rapid-discharge cars it’s delivering 5% less coal, but the shipper is paying the same price. Sometimes more because the fuel burn for the empty return trip is higher.

4. Cost of dumper. The rapid-discharge car only needs an elevated trestle – or even just a trestle with a concrete-lined depression scooped out of the ground surface. The rotary-dumper is expensive to build, expensive to maintain, and also requires more skilled labor to operate and maintain.

5. Physical layout of the powe

[CShaveRR]

7. Flexibility. Rotary-dump gons only go to rotary-dumpers sized for them. Rapid-discharge cars can go anywhere where you can open the doors (manually, too) – you can even run them through the rotary dumper and dump them there, if you want (without rotating them, that is). A shipper may choose to take the cost and tare penalty in order to get the universality advantage.

As I’ve mentioned a number of times before on similar threads, virtually every aluminum coal car built in the past 20 years (be it gondola, standard hopper, or rapid-discharge hopper), and a lot of the steel cars before then, are built with the same overall length. Check the Equipment Registers or UMLER files–53 feet 1 inch. They can rotary-dump those rapid-discharge hoppers if they have the coupler (as most of the newer ones do). If you watch a train of the hoppers go through (at least around here), check for breaks in the dumping hose between the cars. That will give you a clue to the method not being employed to dump them.

You would probably gain little by air-dumping a train of rapid-discharge hoppers at a rotary dumper. It’s likely that the speed that the coal can be moved away from the dumper is not fast enough to handle the hoppers’ higher unloading speed. The hoppers are best utilized where a train can be unloaded without stopping, suggesting that the coal drops into an area longer than a single-car rotary dumper would allow.

[Anonymous]

7. Flexibility. Rotary-dump gons only go to rotary-dumpers sized for them. Rapid-discharge cars can go anywhere where you can open the doors (manually, too) – you can even run them through the rotary dumper and dump them there, if you want (without rotating them, that is). A shipper may choose to take the cost and tare penalty in order to get the universality advantage.

As I’ve mentioned a number of times before on similar threads, virtually every aluminum coal car built in the past 20 years (be it gondola, standard hopper, or rapid-discharge hopper), and a lot of the steel cars before then, are built with the same overall length. Check the Equipment Registers or UMLER files–53 feet 1 inch. They can rotary-dump those rapid-discharge hoppers if they have the coupler (as most of the newer ones do). If you watch a train of the hoppers go through (at least around here), check for breaks in the dumping hose between the cars. That will give you a clue to the method not being employed to dump them.

You would probably gain little by air-dumping a train of rapid-discharge hoppers at a rotary dumper. It’s likely that the speed that the coal can be moved away from the dumper is not fast enough to handle the hoppers’ higher unloading speed. The hoppers are best utilized where a train can be unloaded without stopping, suggesting that the coal drops into an area longer than a single-car rotary dumper would allow.

Agreed, but there are significant differences in the designs of rotary dumpers that have led some car designs to grief, particularly with railroad-owned cars that by definition are supposed to be go-anywhere cars. The experience I recall is with a railroad-owned fleet that when dumped at a certain large mid-south utility folded the top sills badly enough that the cars had to be pulled from service, repaired, and reinforced. And certa

[Andrew_Falconer]

FreightCar America is the current name of the manufacture who used to be known as Bethlehem Johnstown and then Johnstown America.

FreightCar America has a website which lists all the freight cars they produce and the features.

That should explain most of your questions.

Andrew Falconer

[Andrew_Falconer]

www.freightcaramerica.com

Please go to that website for more answers to the coal car unloading questions.

Andrew Falconer

[kevarc]

No it is manned the whole time.

[CShaveRR]

Your point understood, and appreciated, Mr. Hadid.

[beaulieu]

Your point understood, and appreciated, Mr. Hadid.

The common reason for using gondolas over Rapid-Discharge is empty weight, insignificant on short hauls, but it really adds up on the longer hauls. That is a big reason why Gondolas are much more common out of the PRB while from mines in the east Rapid-Discharge is more common.

[Rick_the_Railroader]

They have what is called a pick-up shoe on the BL & AR side of the car which trips the dumping device, and on what the CSXT calls Rotary Dumps which have no doors on the bottom (tubs) of the car the have a set of large arms which clutch the entire car and turn them completely over and dump the coal.

TVAX cars owned by the Tennesse Valley Athority can be dumped either way, as well as GALXs, (Georgia Light & Power), FALXs (Fla.Light and Power) OUCX (Orlando Uitilies Company).

But SJRXs are (tubs) sorta like a Gonadola but is a Coal Hopper must be turned over to dump.