ABCs of Coal Loaders
by Dan Bourque
Large tipple near Prince, WV on the C&O
-Donald Haskel photo
coal to the
rails. In other strip mine operations, long conveyors bring the coal over hills and
valleys to the loader. Let's talk about the most traditional coal loader: the
tipple.
Tipples
The traditional tipple is usually situated near the mine, but it can be served by trucks or conveyors as well. In operation, the coal, in raw form, is brought into the tipple where it is cleaned and sorted. In the tipple, coal runs over various size screens starting with small openings and working down to the largest openings. The different sizes are typically stored separately and loaded over different tracks. The smallest is loaded on the track nearest the "top" of the tipple and each successive track loads larger and larger chunks of coal. In addition to sizing the coal, tipples would often wash the coal and treat it with oil to decrease the dustiness. In many cases, slack coal was stored in a silo rather than a bin to reduce the risks of flash fires.
Truck Dumps
The second type of coal loader is the truck
dump. A truck dump is used when a mine is located some distance away from the rails. The
simplest form of truck dump is a ramp which allows the truck to simply back-up onto a pier
and empty its load into the waiting coal hopper (now outlawed due to a high number of
accidents involving the truck or front-end loader falling into the hopper). Other truck
dumps use bulldozers to load coal that has been dumped on the ground into a conveyor
angled over the hopper car. More modern truck dumps (like Hawthorne on the old Interstate
main east of Norton, VA shown at right) have small crushers which make the coal more
uniform and use conveyor-fed chutes for more efficient loading. Truck dumps typically load
from 1 to 30 cars per day over one or two tracks. Truck dumps are most prevalent in
Eastern Kentucky and Western Virginia and make up the majority of loading points in
modern-day Appalachia.
Flood Loaders
The third
type of coal loading operation is the more modern flood loader. A flood loader can load an
entire train in a relatively short amount of time. Typically, a train is run underneath
the loader very slowly while the coal is emptied via a specialized chute. Flood loaders
(like Tom's Creek, VA shown at left) are very popular as loading sources for unit trains
and currently load the lion’s share of coal with huge operations capable of loading
hundred car trains every day. Today's flood loaders are also typically located
closer to the mainline than their tipple cousins and are often served by miles of
conveyors.
Transloaders
A unique form of coal loader is the transloader. In a transloader operation, coal is brought in from several mines via train. The transloader facility then blends the coal to create the best product for its customer. This coal is typically stored in huge concrete silos awaiting shipment. When a customer needs coal, the transloader typically uses a flood loader at the facility to load a unit train.
One thing is for sure, no two coal loaders are exactly alike! Loaders can be a mix of tipple and truck dump, transloader and flood loader, loaders may even get coal from both conveyors and an on-site mine. These descriptions are merely intended to simplify things a bit.
Coal Loader Evolution in a Nutshell
From the turn of the century into the 1950s, tipples dominated the loading scene. Sized coal was very common, and single car loadings were the norm. The typical coal hopper was a 50-55 ton twin car. In the '50s, 70 ton triple and quad hoppers were quickly becoming the standard. As mines near the tipples dried-up, truck dumps began to increase in popularity. With a truck dump, you could mine several different seams of coal without having to move your loader. In the mid '60s, coal hoppers were growing from 50 and 70 tons to 100 tons or more. As hoppers grew, so did loading facilities. Flood loaders began replacing dozens of tipples as strip mining became more popular. Huge conveyors, some miles long, brought coal in from across the ridges to these giants. Other operations used older hoppers as shuttle cars to ferry coal from smaller tipples and truck dumps to transloading facilities which mixed the coal and loaded from flood loaders. In the '70s, during the energy crisis, the coal boom saw a big increase in the use of unit trains. Unit trains load the entire train at one point and deliver it to a single receiver--usually a power plant. Many new truck dumps were also constructed to handle the increase in traffic due to the energy crisis. By the 1980s, nearly all of the tipples were gone. 50 ton hoppers were rare, and even 70 ton hoppers were being rapidly retired. Today, the truck dumps are still around; but one-by-one, they are slowly shutting down as the need for single car loadings diminishes and the demand for western coal increases.
In the next article, ABCs of Coal Loads, we'll talk about how the different
types of loaders affect the appearance of the coal load. For more pictures of coal
loaders, see the coal
loader photo page. 