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QUESTIONS AND ANSWERS Q: What is a marshalling yard? A: It certainly has nothing to do with the OK Corral. “Marshaling yard” (also spelled with two “l’s,” in British/ European/Pennsy/Canadian Pacificspeak) is what many railroaders in the United States and on the Canadian National call a classification yard. Railroads use classification yards to collect and sort (classify) freight cars for forwarding to their destinations. For example, suppose a train from Green River, WY arrives at the Pocatello, ID yard. The yard crew breaks the train down to begin classification. Cars that are waybilled to destinations switched by trains originating at Pocatello will
be sorted into one track, cars headed for points north into another, and cars destined for the Pacific Northwest into a third. Trim crews will pull the strings of sorted cars and assemble these groups and others into new trains according to the traffic plan.
The time and crew expense required for classifying trains explains the popularity of unit trains. A train consisting of auto racks carrying imported autos from Vancouver, WA to a distribution center in the Midwest doesn’t need to be switched at all en route. A container train can run from the docks in Portland to Chicago, stopping only for crew changes. Coal is generally loaded at a mine and moves directly to a power-generating plant. Sometimes coal cars from several mines are combined into a single unit train.
A classification yard is often part of a larger complex that might include an engine terminal, a car repair shop, or an interchange yard to hold cars destined for a connecting railroad. At bigger sites, trains will terminate in an arrival or receiving yard, where they are broken down to be reclassified. Some high-volume industries like plastics manufacturing or the auto industry might be served by specific yards where freight cars – loaded or empty – are held until they’re needed — MRH
Log into the Union Pacific site at www.uprr.com/customers/intermodal/featured/joliet.shtml to get an overview of how traffic in and out of the Chicago area is handled.
Q: Where can I get good custom decals for my freelanced railroad? A: You can make your own using an ink jet or laser printer – as long as you don’t want them to be white.
Figure 1: Albina Yard, in Portland, OR, where lines from California, Washington and Idaho meet, classifies Union Pacific Railroad traffic moving into and out of the Portland area.
Pocatello formerly had a hump yard, built to handle high volumes of traffic. In a hump yard, cars are classified by pushing them slowly up a hill (or “hump”). They are uncoupled at the top of the hump and roll downhill through a series of switches into the designated track. Retarders are used to control the speed of a car as it rolls. This task is now accomplished by flat-switching – a switch engine shoves cars into the designated tracks. Figure 1
Page 15 • Feb 2012 MRH MRH Questions, Answers, and Tips, page 1
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