I am Modeling an asphalt plant and would like suggestions for a conveyor system to unload the hopper of gravel. This will be a small one to unload one hopper at a time and move the gravel around the plant. My time period is 1960-1976 Erie Lackawanna
Thanks Mike Dickinson
Do you want the conveyors to actually move the material, or are you simply interested in making an accurate model with non-operating conveyors?
If the first, you are opening a large can of worms. Moving model machinery with small parts, tiny clearances and low-power motors doesn't coexist well with grit in any form.
If the second, your best bet is to look at modern asphalt-mixing facilities, then backdate the design of such things as hoppers and machinery casings. The basic technology hasn't changed.
Chuck (modeling Central Japan in September, 1964)
Chuck I do not need it to operate. All I need is something that looks like it would unload the hoppers.
Mike Dickinson
Mike,
First of all, go to Google images for some pictures. I've saved you the trouble of looking up the link:
http://images.google.com/images?gbv=2&hl=en&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=asphalt+plant&spell=1
As you can see there are several examples. Like grain evevators, no two are exactly the same. From what I know of asphalt plants (I believe they are also called "batching plants"), they have not changed a whole lot over time.
Hope this helps.
John Timm
Since you are modeling E-L, which was post-transition/pre-Conrail in bad weather country, I would expect your plant to use covered or fully-enclosed conveyors. Belt type would slope up at about 25-30 degrees maximum. A bucket-type conveyor could be anything from 45 degrees to vertical, with vertical the most usual. The sort of conveyors I am thinking about are the sort included in Walthers' Glacier Gravel and New River Mine kits - and can be scratchbuilt without much effort.
A quick net search of Asphalt ready-mix found a nice selection of companies in the business in various parts of the country, many with plant photos. None were sufficiently detailed to serve as a basis for modeling, but they would have been a starting point. One California outfit had old (1950 built) and newer (up to 2002 built) plants, which showed an interesting shift in bin design but very similar-looking conveyors.
"Bad weather country?" Any place where heavy snow or driving rain can be expected on a regular basis. Liquid or solid water and asphalt paving materials are a poor mix.
I will share some secrets or not so secrets from my Blacktop hauling days.
In a place called Finksburg Maryland (Use google earth) you will see a small rail facility that takes in sand, rock etc. They pull it from the hoppers and chute it off into big piles to be scooped by front end loaders and loaded as needed onto those who come in wanting rock. It is a very small place with a big business.
If you look to the east you will find the CJ Miller's Blacktop plant and if you looked down into the valley you will find another blacktop plant against a hill to the west.
The CJ Miller Facility had large pile of rock sitting on the ground deposited there by front end loader. I will think that a dump truck hauled this very large rock from the rail facility, back and forth all day. In the other Blacktop plant they would get a little bit of rock. I recall hauling waste concrete products dug up and sent to the blacktop plant for scrap. They would chop up this concrete into many little rocks. I dont know what they did with it but there is a fair amount of waste dumped there.
The only conveyors I remember are those directly under the blacktop silos and very short ones to and from the collectors and the fire tube that rotates. Blacktop tends to drip little black blots all over everything underneath the silos and conveyor loading. I always had to go around my dump truck picking off the little black dots from the windshield, hood and roof while the stuff is still hot.
We would get several loads a day of rock and blacktop as the job calls for it. Sometimes we got much rock and very little top. Other times we got all top and no rock. Even once in a while we get the old truck and go into the rail facility to grab 10K pounds of gravel or whatever and they load a dallop on there.
Really BIG blacktop plants have Quarries. Some plants making both concrete and blacktop will dip both into rail, quarries, trucking from other quarries and it's classic of never enough of anything.
Converyors? Sure. There is a American Plant on US 40 at White marsh that would convey the rock and whatever to the tops of the tower.
The one ready mix I worked at, had a square dump box with angled bottom. It poured the sand and rock I loaded into there with a CAT 936 front end loader and the short conveyor took it about 20 feet up into the top of the tower to be mixed into concrete. Always a man with a shovel (Usually me) going around picking up loose rock that bounced and scattered from below the belt.
Really BIG conveyors came out the mountain to feed a coal loader or other stuff. Some of those run for miles. If you found one and followed it for a few miles you usually hit a quarry.
But railcars? Not many or any at all. If there was a few hoppers it would be on a short thick trestle with enough room to dump it's contents straight down where the front end loader got to em. Some were unloading into a small conveyor very similar to the Walthers Conveyor kit and it will make smaller piles to be scooped and sorted.
Coal Power plants have monster Conveyors, they make a pile or three of coal big enough to feed the fires and make electricity for several months. They like it that way.
Limestone powder was conveyed to the tower but railcars got loaded from thier own silos. Cement was similar.
Flyash from a coal plant that I picked up for the ready mix would be conveyed to thier own tower some distance from the boilers. The one at Redfield Arkansas is a good example on Googe Earth. That one is south of Little Rock about 9 miles and 1 mile east of the interstate more or less. You may not get good images because there is a Arsenal down there in the business of disposing of chemical weapons.