…why is that and what do the colors signify? I’ve often wondered.
Thanks
It differentiates the rotary coupler end from the non.
The colors signify which side of the car is equipped with a rotary coupler. The rotary coupler allows the train to be dumped without being uncoupled.
Those are cars with rotating couplers at one end, for use in rotary dump service. The colored end denotes which end has the rotary coupler. There needs to be a rotating coupler at each end of the car or cars on the rotary dumper, it would be very bad to try to rotate a car on a dumper without the proper couplers.
Doug
Usually the rotary coupler (and therefore the colored end) is found on the A end of the car (the end where the hand-brake wheel isn’t). Occasionally, though, a car will be built or modified to have rotary couplers at both ends. This permits an entire train to remain intact when it has distributed power at the hind end (the double-rotary car can be anywhere in the consist, so long as the cars at the end of the train have rotary couplers next to the locomotives.
Back in the good old days (1970s or thereabouts), the big aluminum coal gons of Detroit Edison were expected to remain pretty much in numerical order. To this end, the odd-numbered cars had rotary couplers at both ends, and the even-numbered cars had no rotary couplers. It didn’t work very well apparently, because nobody else (including Detroit Edison on later purchases) did it. You can still see some of these cars in scrap-metal service for various companies (especially AMG Resources–reporting marks AMGX).
Okay…Thanks guys. Does that mean that the coal is not discharged from the bottom of the car instead the cars are ‘rolled over’ one at a time, hence the need for a ‘rotary’ coupler? i’m trying to imagine the process, but I’m drawing a blank here. Also, why the different colors?
Color is only a matter of car owners preference.
It depends on the car, and the unloading facility.
There are hoppers with bottom dump doors and rotary couplers. They can be unloaded “conventionally” at receivers that don’t have a rotary car dump, or turned over at those that do.
Other cars don’t have bottom dump doors and the only way to empty them is by turning them over. These cars technically aren’t hoppers but gondolas. Carl and the other freight car experts would probably know for sure, but I think most new cars being built for unit coal train service are this type.
Jeff
Ted, I’m trying to remember whether it was in this forum that I saw an extensive series of rotary-dump pictures, but I couldn’t find any in my quick search.
Many of the coal cars in use today are gondolas–there’s no way they can be emptied through the bottom. I suspect, though, that many plants in your part of the country have opted for bottom-discharge humping with air-actuated hoppers. Even so, you’ll find that many of the hoppers have rotary couplers on one end, so that they can be used at locations where rotary dumping is the only option.
I’ve seen just about every color imaginable on a rotary-coupler end. No purple yet, though, and I’m sure that the pink I saw was just faded red.
Oh…Okay. It’s starting to make sense, the cars are somehow rolled over and then set upright again on the rails. Still trying to imagine how that’s done, but, for now that satisfies my curiousity.
Carl, your suspicions are correct. We don’t have any coal fired power plants this far south and there is practically no coal traffic on South Florida rails. Fuel oil and natural gas power plants are most common in Florida. We also have at least two nuclear power plants down here. There are only a handful of coal fired plants that I know of. They are in Indiantown, Satellite Beach and Orlando, the closest still being over one hundred miles from where I live.
From what I have seen coal is delivered in open hoppers which discharge from below into a pit covered by steel grate. I believe what you’re describing is what I’ve heared referred to as a ‘bathtub’ gondola, typical in scrap metal service down here.
Not just the car is turned. The rotary dumper is like a truss bridge that turns upside down the car is pulled on and clamped to the track. Then the bridge, track, and car are all flipped. Here’s on in Norfolk Virginia http://maps.live.com/default.aspx?v=2&FORM=LMLTCP&cp=q4cnk58n5kxy&style=b&lvl=2&tilt=-90&dir=0&alt=-1000&scene=18506947&phx=0&phy=0&phscl=1&encType=1
Three basic methods of moving coal by rail:
- Cross hoppers with manual doors (“cross” because the doors run across the car), typically four for a 100-ton car. The doors have latches that are manually operated, the doors swing open by gravity, and after dumping the doors are closed and latched by hand. The advantage of this type of car is that it is inexpensive, durable, and can be dumped virtually anywhere, even at a “facility” as basic as right on a team track, and shovel out the contents that fall on the track by hand. They can be rotary dumped if fed into the dumper one at a time, and rotary dumpers designed for this type of car were constructed at coal piers such as Norfolk, Toledo, and Chicago, and at many steel mills with rates of 2,000-3,000 tons per hour. They continue to be used by numerous industrial customers and small power-plants. Only a relative handful have been constructed with aluminum bodies. The Pocohontas coal roads built vast fleets of these in 50-ton and 70-ton size, most of which are now gone. N&W, UP, MP, D&RGW, C&O, PC, SR, IC, and BN built immense fleets of this type of car in the 100-ton size, most of which are still in service on successor roads. Not very many were built for private owners, but quite a few are now in lease fleets such as Helm. This type of car with a steel body is suitable for moving taconite pellets and often are used in that kind of service. With taconite they tare out long before they cube out. They are useful for coke but for that commodity they will typically cube out before they tare out. They are also used for bauxite, copper concentrate, and other finely crushed minerals, but really don’t have the door opening size to be suitable for aggregates or other large-diameter minerals. Any time a commodity is switched the car has to be cleaned. Conrail rebuilt a large fleet of 90-ton cross-hoppers into rot
High sulphur coal when wet leaches sulphuric acid. Illinois Basin coal has high sulphur content.
Very true. But L&N cars hauling the same rotten Western Kentucky coal didn’t seem to have this problem. MKT cars, now that I think about it, also had side-sheet issues. Perhaps it was the combination of high-sulfur coal and hand-to-mouth finances.
RWM
After a litttle bit of research over at www.rrpicturearchives.net and from your replies I’ve learned that some rotary-coupler equipped cars are hoppers and some are gondolas. AAR Type J311 seems to be the most commonly used gondola, easily indentified by the depressed floor between the trucks vs. having 4 or 5 hopper doors. Type K340 hoppers do not have rotary couplers, but Type K341 hoppers do. Both types are used to haul coal and are the types of cars that I do see down here from time to time.
[bow]Thanks to everyone for enlightening me on the subject of rotary dumping, a technology that I was totally unfamiliar with until tonight. [D)]
The ConRail conversions rose up an bit CSX when those cars were used on coal trains from the Mon District to Cross, SC. Trains were 105 cars…no problem over the Sand Patch grade because a rear end helper was used. Out of Brunswick over Barnesville Hill was another story…invariably the weakest knuckle/coupler would be found when the train had head end power only. Even though train sizes are within the range of not needing to be shoved…if you want to get the train off the division with one crew…shove it or you will be spending hours trying to correct the weaknesses that gravity find.
I should have said, “rarely presented a problem from my parochial perspective as a west-of-Chicago railroader.” I had always presumed Conrail knew what they were doing for their territory. I didn’t realize they had migrated out of Conrail territory post-merger. My sympathies!
RWM
Resurrecting a very old thread. Just watched a coal train pass an online railcam with colored markings on opposite ends depending upon which side you were viewing. The sides closest to the camera all had markings on the trailing end of each car. As the train rounded a bend, and the opposite sides of the cars came into view, all the markings were on the leading end of each car. This was true for the entire train - not due to some double-ended transition car somewhere in the middle.
In this case, what do the colored markings signify?
As a matter of switching with such cars - the instructions will be to have the painted ends, on the side you are switching the cars from, to have the painted and all in one direction.
In most switching things are arranged so that the switchman works from the Engineers side of the locomotive, thus the switchman views his cars from that one side.
Coal cars with painted ends have rotary couplers, so the cars can be rotated for emptying. If you end up with cars with painted ends together, or non-painted ends together - one of the situations will have standard couplers coupled together and thus the cars cannot be rotated.
But what he’s reporting is that he sees the colored end painted on the A end of the car on one side and the B end on the other, which would mean rotary couplers on both ends if the older definition applied. If designating a ‘rotary end’ the same color would mark that end on both sides of the car.