I can not say I have much in the way of expereance whem it comes to watching trains that have open hoppers loaded with coal, but, the other day, I noticed something that I can’t help but think about when I see it.
Many times when I see models of open hoppers loaded with coal, they are filled to the brim and then it’s heaped up even further ( sometimes perhaps as much as a scale 3 ft higher than the sides of the hopper car ), yet in the case, of the prototypes I have seen localy, it looks like they are actualy loaded so that the coal comes up to more or less 3/4’s - 4/5’s full and heaped so that perhaps only the last 18 inches of the top of the coal is actualy seen over the sides of the hopper.
Now I realise that different types of coal and the size of pieces is going to play a part of the issue when it comes to the angle of repose that the coal will take on its journey to it’s destanation, so, am I just seeing things or is this actualy happening?
Coal will settle as it travels. When a car is loaded, there will be voids ranging from small to sizeable in the lading. Due to the motion of the car and the frangible nature of the product, the coal will gradually shift to fill those voids. If it has to travel any distance, by the time it arrives and has to be unloaded the coal will have compacted into a near-solid mass. That is why there are such things as rotary unloaders (reverse the effect of gravity and the coal ‘un-compacts’) and car shakers.
I recall, back in those dim days when coal was used as a domestic fuel, watching workers poking upward into the open hopper doors with long rods to dislodge compacted coal. I was running around in shorts, so I doubt that the load was frozen.
Could be many things, car was built to handle one density of coal and is handling a heavier grade, coal settled, loader is set for a lower car, the car is a 286 cap car and is only loaded to 263,000 lbs.
The coal is often weighed as it is loded in the car (scale on the belt or chute) and the loading system is designed to load the cars so as not to overload the cars.
Hoppers, like any other freight car, are loaded by weight, not volume. A coal load by weight of 100 tons and heaped high will still be 100 tons when it reaches it’s destination, although it’s compacted.
This very issue got addressed twenty five to thirty years ago in RMC; they had run a feature about coal mine modeling and a reader observed the same thing as you have. It certainly did appear from photographs - prototype as well as model -accompanying the article that modelers do tend to crown their coal loads just a mite too high.
I’m glad you brought this issue up because I had forgotten clean about it; I will soon be fabricating loads for my hopper fleet and this is worthy of attention.
I have not seen the actual loading of coal, but, I have seen the hopper cars just a few miles from the destination ( local power plant ), and I seen them from an overpass as they have gone under, and from a few yards from the tracks as they have gone by - close enough that if the wind was right I could probably spit across the tracks.
Now, not being a coal expert, I will add my 2 cents worth here anyway. I agree about the coal being loaded by weight. Some coal (most I suspect) is destined for power plants and is very fine compared to coal used in fireing locomotives. Thus a given weight of the fine coal will take less space then the coarse coal. Also I suspect that some coarse coal could fill a hopper and not come close to the weight limit of the car. Years ago 40’s and into the 50’s coal was used by the rail roads to fire locos and also as heat in the old pot belly stoves, not to mention that a lot of houses were heated by coal fired boilers back then and hopper cars in the era were pretty much loaded to over flowing like many models are portrayed. My understanding of the coal used in modern power plants is very fine (almost a dust), then ground at the plant and injected into the boilers like oil would be to get the cleanest possible fire. The loads in or models appear to me to be at least 2 or 3 inch lumps compared the 1/4 inch or so coal hauled to power plants. Just my observation is all, not an expert’s answer. Ken
Interesting topic. The Reading Company shipped a lot of Antracite, some of it from their huge Port Richmond docks in Philadelphia. I have seen drawings of the track lay out at Port Richmond, They had a long shed, mayber 10 cars or so, where in they thawed out frozen loads. I guess they used steam in the shed to do it.
Agreed. I also believe that you will agree that those loads are a lot lower than the freshly-filled loads in the post preceding yours. At the loadout in the Powder River Basin they are almost overflowing. At Castle Rock, several hundred miles down the road, they have settled at least a foot.
That’s why I asked the original poster how close he was to the loadout. His answer indicates that he’s much closer to the destination than to the origin.
My own modeling will simulate the ‘freshly loaded’ appearance, since my ‘loads out’ will be rolling out from under the tipple. It remains to be seen if the pool charcoal live loads will settle as they move (up to 50 scale kilometers, several times around the oval) toward the one place on the railroad (cassette off the Mikasa yard) where they can be emptied. The ‘fixed loads’ in unit train cars won’t have the distance to travel, or the opportunity, since the blocks of foam with ‘coal’ glued to them are unlikely to settle.
Chuck (modeling Central Japan in September, 1964 - with a tanko that can live load ‘coal’.)
The CO loads may not have settled at all, (probably though) but instead may not have been topped off. After going through the main flooder in the prb, trains can also go through a top off flooder.
Whether every train does or does not, I don’t know. Anyone ?
I would call it dramatic effect for the HO load, enough to show its loaded.
I have tinkered with the possibility of really loading and unloading and said to myself…naaaw, I won’t go this far. How long and far a modeler wants to deal with loading and its effects is how much trouble you want to go into.
For modeling purposes and getting the details right, sure. Studying how its loaded helps in the realism. For me, I am doing a serious coaling operation but its going to be a put/take deal, drop the cars in the setoff (power plant), goes thru a disguised tunnel to a coal mine and its picked up. Simple, and no changing loads around. A cheat, but works. So you have always one loaded train and one empty train, at least.
I also run “live” coal loads, using either coke breeze (this one isn’t very fully-loaded):
or locomotive traction grit:
Both materials settle during transit: the coke breeze is a mixture of particle sizes right down to dust, while the traction grit is pretty uniform in particle size. A two-bay hopper loaded with coke breeze weighs 4 oz., while a similar car loaded with the grit weighs in at 8 oz. This is something to consider when determining train length and selection of motive power. [swg]
I live in Colorado Springs CO, about 40-50 miles south of where the pictures were taken, and these are the same train cars I see - almost every day, many of which are delivering coal to one of the the local powerplanst here.
OTOH, while these loads can just be seen peaking out over the top, it doesn’t look like they are about to overflow onto the tracks ( as if someone tried to cram every last piece of coal into them ), like I see in many model coal cars.
It is this, that I see and not hopper cars filled to the brim ( and then some ), that made me wonder if there was a reasion that many model coal cars ( that had coal full to the rim and piled even higher ) didn’t appear to be prototypical to me.
It is the appearance of being filled to the rim and further heaped up even more that didn’t appear right.
I may have to try coke breeze, since charcoal seems to have static cling problems!
As far as weight, I cheat. The mine is at the highest point of the railroad, so all loaded movements are down the steepest grades (4%.) The live loads will routinely get a pusher up the 2.5% from Haruyama to Tomikawa.
The only problem with the coke breeze is that it’s quite dirty: it makes for quite a bit of dust when loading or unloading the cars. I do that off-layout, so it’s not a problem in my situation. The stuff that I’m using was run through a sieve to remove the coarser particles, but I wish that I could remember where I stored the bigger stuff: after seeing Kurt_Laughlin’s second photo, it seems that it would be quite useable.
Coming from Australia,Blue mountains about 190k/lms,80-85 miles roughly,west of sydney.Unit coal trains of 64 or 86 cars come through here all the time-various coal mines further west transport coal over the mountains for export,and other uses i’m not sure of ,cause there’s no power station in Sydney.But i do have to say that different grade coals settle differntly on transport.The finer grade coal tends to shake’rattle’n’roll itself into the hoppers on transport,making them look less full-it just vibrates itelf into itself!Larger grade coal,well, doesn’t settle to much and,up here with 2.5% grades likes to tumble out around tight bends. But either way,what is loaded into the cars-89 tons-arrives at its destination,minus the bits that fall off round corners.But what i do like is seeing the polished metal inside the empties as they head west again,coal scrapes metal and any paint on it off,leaving what looks like a highly polished surface-modellers should paint the inside of there hoppers a gunmetal colour-empties of course-it looks clean,but used.Try it you’ll see what i mean!!! mick
