I’m wondering how long it take to load a center flow covered hopper with plastic pellets and how long it take to load a tank car with chemicals, for instance chlorine? Are we talking minutes, hours, a day…?
/Mattias
Any particular reason it has to be plastic pellets and chlorine?
There is a factory accross the street that makes plastic sirynges (SP?) for hospitals. They get their plastic pellets via covered hoppers. They usually have 6 to 8 hoppers sitting on their siding. Those cars will sit there for 1 to 2 weeks before being switched out for loaded hoppers. The factory just runs a large air hose and discharge hose out to the rail cars.
I’m planning to model a plant making plastic pellets and chemicals so that’s why I wrought about those commodities, but maybe it takes about the same amount of time regardless of what the car will be loaded with. The thing that I’m after really is if the same loading spot in the plant should be switched once or several times a day.
/Mattias
Most of your larger plants are switch more than once, or have an in-plant their to do it for them. exact time of loading, i’m not sure, but I imagine it couldn’t be more than an hour or so per car, probly less. The turn around time is a couple of days, though. The cars are brought in based on load projections and per diem charges. Then they got to be inspected before loading. In plants with storage yards, a car can get moved two or three times before it leaves the property.
While were on the subject, how long does it take to load/unload a grain hopper, how about a coal car’s loading/ unloading time?
I used to run bulk cement in a pressurized tanker (Heil or Butler) for trucking companies. Those usually require about 12 pounds of pressurized air inside the tank. I think each of the three (Or two) pots (Sometimes many as 5) where the product goes to the pipe to be discharged up to the silo will need approx 15 minutes. So, a good blow will need about less than a hour’s time especially when driven by a electric motor and not by the truck’s exhaust.
Mortor would take longer. Flyash you could “Hammer” up the pipe all day.
I have no experience with pellets however I think that stuff would just about float out of that tank and straight into the silo under sufficient pressure.
I dont know about why they would keep covered hoppers at that plant for so long. I think it may have something to do with maintaining a supply of material on hand to support production with a reserve.
Coal would rumble out of the hopper in no time. It would take about the same time as a dump trailer or truck with stone. “THUMP” and yer gone. It takes longer to get the paper work signed properly so you can get your pay for it.
I have heard of covered hoppers that are lined for specific product and think that they would need to be blue-flagged and sit for a long time to get the stuff out.
Liquids are the easiest to get out of a tank. Milk for example needs less than a hour to have the Dairy’s small pump to move 30,000 pounds of product into the facility. Just make sure that you have yer hatch open otherwise the negative pressure will crush that tank just like you stomp an empty can.
Even box trailers can behave like tankers if the product’s liquid weight is more than that of the empty tare gross weight. Ive hauled Whiskey out of that Seagrams in Maryland while the bottles swayed and jingled in the box causing the rig to act just like a milk tanker with the liquid slosh.
Might be true for a rotary dumper - The unloading facility where I work dumps from bottom into a hopper where it’s moved by a conveyor system. I still haven’t figured out how long it takes to dump a car, but it’s longer than a few minutes. I’ve never had the time to sit and time them between cars (the stick is advanced car-by-car over the receiving hopper).
Now-a-days, with Rotary dumps around it takes a matter of minutes to go through a whole coal train. two or three cars go into the rotary dump and the thing spins them almost 180 degrees and dumps all the contents out. The the train is pulled a long by a pulley system. It’s quite fascinating really. I have seen it done.
Loading coal cars is probably a little slower and harder on the crew. One car at a time go under a coal chute and an operator operates the chute. He loads it and then the crew pulls the train ahead one car. And for about hour and a half the crew and operator can go through this loading process.[X-)]
Grain hoppers take a little longer to load. At the elevator, some people go up on the car and open up the hatches on the cars roof. Then there are a couple of chutes that the men place into the car and it begins to load. It’s actually a lot slower than coal. So they may stick around for a few days.
Unloading is really fast though. Under the grain car there is something called a hopper. You will see three on a usual grain car. These are usually air powered. They open the hoppers and out comes the grain. This will happen over a pit in an unloading center.
Happy railroading[(-D]
James
Rotoy-dumps dont move all that fast. Maybe about as fast as a second hand on a clock. I think it boils down to about ten minutes or so per hopper. Dont quote me on that, it’s a guesstimate.
Actually its more like minutes per car/2-3 car sets. A whole train is probably around an hour.
WHen we dumped rotary dump cars at the power plant up near cheyene took about 6 hours for 120 cas. this was a single car at a time, so about 3 minutes per car for the pulley system to pull the train foward, rotate and dump car, rotate back to up right and pull train forward to next car.
Now at Public Service in denver took about 2 hours to dump 60 cars through bottom doors, enigineer set the train to travel at a slow speed somewhere around 4 to 8 miles an hour and pulled train over the dumper, each car was automatically opened and dumped than closed. This time included setting up the first car and finding the speed at which the utility wanted us to run.
I havent had a chance to see them load coal but I know its done with fload loaders and they continue to pull the train through the loader at slow speed train doesnt stop. This is the way its done in the powder river could be different at other places.
Loading grain trains is wildly different from elevator to elevator, single track pull throughs can load in about 10 hours from the time the train is recieved to about 30 hours for a elevator that has multiple tracks. This time includes inspection of cars for contamination, so actuall loading of the cars is faster than that but not sure exactly how long.
Plastic plants around this area will recieve several different types of plastic and based on plant usage typically a car will be spotted and stay for about a week to unload as they use the plastic, but have had cars ready to pull in as short as a day. The plastic plants around here store the plastic in the car rather than on site in a silo.
Does anyone know of pictures or better yet video of rotary dumping taking place?
Here’s a picture for you.
Grain loading sometimes goes quick. Usually we spot a set of 25 and they are ready the next day or so.
Ballast loading is usually at the rate of 1200 tons per hour. That is when everything is working properly. About 12 cars per hour.
Coal unloading can take quite a while if it is cold out. The coal freezes. Could be down to 4 cars a day, instead of 12.
Grain unloading is by gravity. Open the hatches and let 'er dump. Cement goes pretty quick as well, but they hook a vibrator up to the hoppers to speed things along.
4 cars a day? Are they unloading the coal by shoveling it out? [?]
That was at the UW Heater, Madison WI. About 0 degrees for the daytime high. If it was loose enough to shovel, they probably would have. They don’t have a thaw room or anything, out in the open. Torches, picks, implements of destruction, etc., to get it out. Then they would bash the cars around with a front-end loader, bend up the corner posts, grab irons, pin lifters, etc.
WOW! Thanks, I have never seen this done before.
The co-gen here has a very LARGE vibrator to help unload the coal. Shakes the ground for quite a distance around the dump building (they bottom dump). I’ve never seen it, but it’s on my list…
Every now and then you’ll see one loaded hopper sitting out by itself - most likely frozen and set aside to deal with ‘later.’
Many years ago a phosphate rock mine in Idaho tried to extend the shipping season of ore into the winter - so they sprayed the cars with antifreeze before loading them with rock. At the concentrator end of the run the pulled the treated cars into the rotary dumper and rotated the first car. Thunk -out comes the rock - in one frozen solid 50 ton chunk. The antifreeze worked but the ore still froze. They had to break up the popsicle with jack hammers!
dd