Unloading Plastic Pellets

I recently picked up the Walthers Paper Mill in N-scale ( an excellent value at under $40) to use the smaller building as a power plant, a perfect destination for my coal hoppers. After putting it together, I went ahead and assembled the main building, even though I had no concrete plans for it. It is huge. After looking at it for several days sitting on my table, I thought, "Hey, that would make a great plastics factory." (One of those 'hey' moments that took on a life of it's own, and quickly got out of hand. I'm sure everyone here has had at least one of those moments.) Using the tanks that came with the kit, as well as adding some from an HO cement plant, I now have a reason to go buy some 4-bay covered hoppers as well as chemical tank cars. The problem I have is how to unload the plastic pellets from those hoppers. I know they are pneumatic unloaders, but I can't find any pictures or diagrams of the piping or hookups. ( I have the Kalmbach 'Industries' book that has a plastics plant in it, but it doesn't show any detail either.) I really don't want to hide this procedure behind a retaining wall, so I would appreciate any help you could give me.

Thanks, Don

 

i think there is a little roof thing which houses the car that is bieng unloaded and you can still see the car and the bottom which will consist of the bays on the hoppers over a pit or small hole with a conveighor (help me out here) belt in a pipe leading out of the pit into an elivaitor whell at least thats how i think it would be

i had a really bad hey moment one time i wanted to build something in the city so i was like hey why not a street run and that was the worst hey moment ever

 

Most plastics granules are pumped/sucked by vacumn pressure through hoses from the plant to storage silos. The hoses are designed to fasten to outlet gates on the ends of the hoppers underneath the car to unload it.

Plastics plants come in all sizes from tiny (just a hose coming out of the ground) to huge with several tracks, hoses, piping and silos. It's your pick.

Barry

 

Thanks for the replies. The real question I have is are there devices that hook-up automatically to the bottom of the hopper, or do workman have to manually connect the pipes. Also, do they typically unload one car at a time or can they do multiple units? My plant is going to be fairly large (for N-scale at least), able to handle three cars at a time, if that's prototypical.

Don

 

The hose are coupled and uncoupled manually. In one industrial park I switched, there were three different plastics companies: One had no spur and unloaded cars about every sixth months on another customers lead, another at the end of this track had two separate tracks which each could handle two cars each and a third had its on two tracks to handle four cars on one and five on another.
Generally larger plants with bigger pumps can handle several cars at a time.
One thing to keep in mind at larger facilities depending on the product manufactured, they often have tall buildings so the resin granules when they are heated can be blown with forced air to create plastic film and the structures for this equipment is tall
Barry

 

Thanks for the info Barry. I think I have a better idea of what I need to do now. I may also have to incorporate that nugget about making the film. Thanks again.

Don

 

Don, I'll go by one of our customers tomorrow morning and get a few pictures of the unloading process for you. The basic vaccuum setup is pretty standard with just a single pipe running the length of the unloading segment of the track and various "ports" tied in either via 90 degree or 45 degree tees. They simply uncap which port they wish to feed into, hook one end of the hose to it and then the other end to the car. As the hose is a flexible corrugated plastic (how it must be for whomever makes those hoses - they unload the cars using hoses made from the very same plastic coming out of the cars leading to the old chicken and the egg question... ), most of our customers unhook them completely and store them indoors when not unloading to protect them from being stolen or damaged by the weather.

The Airflow Hopper is the standard transport vehicle for plastic pellets although occasionally some resins will be shipped as a liquid in a tank car. You can find tons of pictures online of these hoppers with the various reporting marks of the chemical companies and oil companies (ACFX, CGLX, MOBX, ECUX, EQUX, UTCX, XOMX, NDYX, NAHX, PSPX, WLPX, etc).

 

I work in a plastics factory, over here in England, and our plastic pellets are delivered in 30 foot containers by truck. They are coupled up using 4 inch plastic tubing,to the storage silo, by the truck driver. They use a blower unit mounted on the trailer, driven by a power take off from the trucks engine, This blows the pellets, up a fixed pipe that runs to the top of the silo. Apparently some factories use their own source of air to unload the trucks, I would guess the railroad hoppers would also use a factory based air supply.
These pelletsare clear, we add coloured pellets to them, to get different coloured bottles.

Ronzzr11

 

I popped by one of the local plastic companies and snapped a few pics this morning for you. I've delivered to this company before a couple of times but the main one I deal with is in another town and has a larger yard for car storage. If I get out there anytime soon I'll take a few pics of that yard. But here's the set I took this morning. Hope they help a bit. Aclo - a set on Flickr

 

I am using the same building for the same kind of business. The unloading of plastic pellets can be done simply with hoses connected to the cars and running into the building. All of the power and vacumn componants for this method of unloading would be in the building and not modeled.

Joe

 

Don,

It takes about 5 minutes to hook up a pipe to a railcar. The pellet/resin cars are equipped with bottom unloading tubes with end caps. The end caps are hinged and locked into place with a screw/bolt system. The worker comes out cuts the securement theft device off, unscrews the screw/bolt system, then attaches the unloading pipe. The unloading tube has an internal rod that runs the length of the tube and in the shipping position holds the plasitc/resin in the car. This rod has a lever on it that allows you to turn the rod and release the plastic/resin into the unloading tube and then vacumn it out to the plant or truck for delivery. I have photos of this if anyone would like me to post.

Joe

 

Wow, what a great community! Now I need to thank friscobob, CAPFLyer, Ronzzr11, mavrick0, and Joe for your responses. Your pics, mavrick0, made things much clearer. (And I definitely would appreciate any and all other contributions as well.) But now I have a few more questions. If it takes about 5 minutes to hook up a hose, how long does it take to completely unload the hopper? And since these are 4-bay hoppers, do they hook a hose to the bottom of all 4 gates, or can they unload from just one?
Thanks again, guys. Don