Coal train

Rail freight transport is the use of railroads and trains to transport cargo as opposed to human passengers.

A freight train or goods train is a group of freight cars (US) or goods wagons (UIC) hauled by one or more locomotives on a railway, transporting cargo all or some of the way between the shipper and the intended destination as part of the logistics chain. Trains may haul bulk material, intermodal containers, general freight or specialized freight in purpose-designed cars. Rail freight practices and economics vary by country and region.

When considered in terms of ton-miles or tonne-kilometers hauled per unit of energy consumed, rail transport can be more efficient than other means of transportation. Maximum economies are typically realized with bulk commodities (e.g., coal), especially when hauled over long distances. However, shipment by rail is not as flexible as by highway, which has resulted in much freight being hauled by truck, even over long distances. Moving goods by rail often involves transshipment costs, particularly when the shipper or receiver lack direct rail access. These costs may exceed that of operating the train itself, a factor that practices such as containerization aim to minimize.

Traditionally, large shippers build factories and warehouses near rail lines and have a section of track on their property called a siding where goods are loaded onto or unloaded from rail cars. Other shippers have their goods hauled (drayed) by wagon or truck to or from a goods station (freight station in US). Smaller locomotives transfer the rail cars from the sidings and goods stations to a classification yard, where each car is coupled to one of several long distance trains being assembled there, depending on that car's destination. When long enough, or based on a schedule, each long distance train is then dispatched to another classification yard. At the next classification yard, cars are resorted. Those that are destined for stations served by that yard are assigned to local trains for delivery. Others are reassembled into trains heading to classification yards closer to their final destination. A single car might be reclassified or switched in several yards before reaching its final destination, a process that made rail freight slow and increased costs. Many freight rail operators are trying to reduce these costs by reducing or eliminating switching in classification yards through techniques such as unit trains and containerization. In many countries, railroads have been built to haul one commodity, such as coal or ore, from an inland point to a port.

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