Freight rail transport

When considered in terms of ton-miles (tonne-kilometers) hauled per unit of consumed energy, rail transport is more efficient than other means of transportation. Additional economies are often realized with bulk commodities (e.g., coal), especially when hauled over long distances. However, rail freight is often subject to transshipment costs, which may exceed that of operating the train itself, a factor that practices such as containerization aim to minimize. Bulk shipments are less affected by transshipment costs, with distances as short as sufficient to make rail transport economically viable. 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.

Overview

In Europe (particularly Britain) many manufacturing towns developed before the railway. Many factories did not have direct rail access. This meant that freight had to be shipped through a goods station, sent by train and unloaded at another goods station for onward delivery to another factory. When lorries (trucks) replaced horses it was often economic and faster to make one movement by road. In the United States, particularly in the West and Mid-West towns developed with railway and factories often had direct rail connection. Despite the closure of many minor lines carload shipping from one company to another by rail remains common.

Many rail systems have turned to computerized scheduling for trains which has helped add more train traffic to the rails. Overall, most businesses ship their products by rail if they are shipping long distance because it is cheaper to ship in large quantities by rail than by truck; however shipping remains a viable competitor where water transport is available. Economics of scale are achieved because less labor and energy is required to haul the same amount of cargo.

Traditional transport of manufactured goods was with boxcars (US) or covered goods wagons (UIC & UK), where the goods were manually loaded and unloaded off the wagon. During the 1960s containerization has made this extra level of labour-intense work unnecessary; while the containers must be moved onto or off the wagons with cranes, the content in the container remains constant from sender to receiver. Containers allow easy change of mode from road and sea and rail.

freight train west of Chicago in 1992.]]

Intermodal freight systems favoring road transport often carry road wheels with the cargo. In some countries rolling highway trains are used; trucks can drive straight onto the train and drive off again when the end destination is reached. A system like this is used on the Channel Tunnel between the United Kingdom and France. In other countries, the tractor unit of each truck is not carried on the train, only the trailer. Piggy back trains are the fastest growing type of freight trains in the United States, where they are also known as trailer on flat car or TOFC trains. There are also roadrailer vehicles, which have two sets of wheels, for use in a train, or as the trailer of a road vehicle.

There are also many other types of wagon, such as "low loader" wagons for transporting road vehicles; there are refrigerator vans for transporting food, simple types of open-topped wagons for transporting minerals and bulk material such as coal, and tankers for transporting liquids and gases. Most coal and aggregates are moved in hopper wagons that can be filled and discharged rapidly, to enable efficient handling of the materials.

Freight trains are sometimes illegally boarded by individuals who do not wish, or do not have the money, to travel by ordinary means, a practice referred to as "hopping." Most hoppers sneak into train yards and stow away in boxcars. Bolder hoppers will catch a train "on the fly," that is, as it is moving, leading to occasional fatalities, some of which go unrecorded. The act of leaving a town or area by hopping a freight train is sometimes referred to as "catching-out", as in catching a train out of town.

Containerization

Containerization is a system of intermodal freight transport cargo transport using standard shipping containers (also known as 'ISO containers' or 'isotainers') that can be loaded and sealed intact onto container ships, railroad cars, planes, and trucks. Containerization has revolutionized cargo shipping. Today, approximately 90% of non-bulk cargo worldwide moves by containers stacked on transport ships; 26% of all containers originate from China. , some 18 million total containers make over 200 million trips per year.

Use of the same basic sizes of containers across the globe has lessened the problems caused by incompatible rail gauge sizes in different countries. The majority of the rail networks in the world operate on a gauge track known as standard gauge but many countries (such as Russia, Finland, and Spain) use broader gauges while many other countries in Africa and South America use narrower gauges on their networks. The use of container trains in all these countries makes trans-shipment between different gauge trains easier.

Double-stack containerization

Most flatcars (US) or flat wagons (UIC) cannot carry more than one standard 40 foot container on top of another because of limited vertical clearance, even though they usually can carry the weight of two. Carrying half the possible weight is inefficient. But if the rail line has been built with sufficient vertical clearance, a double-stack car can accept a container and still leave enough clearance for another container on top. This usually precludes operation of double-stacked wagons on lines with overhead electric wiring. However, the Betuweroute, which was planned with overhead wiring from the start, has been built with tunnels that do accommodate double-stacked wagons so as to keep the option to economically rebuild the route for double stacking in the future. The overhead wiring would then have to be changed to allow double stacking. Lower than standard size containers are run double stacked under overhead wire in China.

In the United States, Southern Pacific Railroad (SP) with Malcom McLean came up with the idea of the first double-stack intermodal car in 1977. SP then designed the first car with ACF Industries that same year. At first it was slow to become an industry standard, then in 1984 American President Lines started working with the SP and that same year, the first all "double stack" train left Los Angeles, California for South Kearny, New Jersey, under the name of "Stacktrain" rail service. Along the way the train transferred from the SP to Conrail. It saved shippers money and now accounts for almost 70 percent of intermodal freight transport shipments in the United States, in part due to the generous vertical clearances used by U.S. railroads. These lines are diesel operated with no overhead wiring.

Double stacking is also used in Australia between Adelaide, Parkes, Perth and Darwin. These are diesel only lines with no overhead wiring. Double stacking is proposed in India for selected freight-only lines. These would be electrified lines with specially high overhead wiring.

Bulk

Bulk cargo is commodity cargo that is transported unpackaged in large quantities. These cargo are usually dropped or poured, with a spout or shovel bucket, as a liquid or solid, into a bulk carrier's hold, railroad car, or tanker truck/trailer/semi-trailer body. Bulk cargoes are classified as liquid or dry, but only the latter are normally transported as bulk on rail, the former being freighted in tank cars.

Hopper cars are freight cars used to transport loose bulk commodities such as coal, ore, grain, track ballast, and the like. This type of car is distinguished from a gondola car (US) or open wagon (UIC) in that it has opening doors on the underside or on the sides to discharge its cargo. The development of the hopper car went along with the development of automated handling of such commodities, with automated loading and unloading facilities. There are two main types of hopper car: open and covered; Covered hopper cars are used for cargo that must be protected from the elements (chiefly rain) such as grain, sugar, and fertilizer. Open cars are used for commodities such as coal, which can get wet and dry out with less harmful effect. Hopper cars have been used by railways worldwide whenever automated cargo handling has been desired. Rotary car dumpers simply invert the car to unload it, and have become the preferred unloading technology, especially in North America; they permit the use of simpler, tougher, and more compact (because sloping ends are not required) gondola cars instead of hoppers.

Heavy-duty ore traffic

The heaviest trains in the world carry bulk traffic such as iron ore and coal. Loads can be 130 tonnes per wagon and tens of thousands of tonnes per train. Daqin Railway transports more than 1 million tonnes of coal to the east sea shore of China every day and in 2009 is the busiest freight line in the world Such economies of scale drive down operating costs. Some freight trains can be over 7 km long.

Special cargo

Several types of cargo are not suited for containerization or bulk; these are transported in special cars custom designed for the cargo.

Liner train

A "liner train", or "freightliner", is a UK term for a train carrying intermodal containers. The name was coined by Richard Beeching in the 1960s, and later became the Freightliner sector of British Rail. This was sold off as a private enterprise, Freightliner, in 1995, as part of the privitisation of BR. In railway enthusiasts' slang, "freightliner" or "liner" may mean either intermodal services run solely by Freightliner, or intermodal services in general. Additionally, a "bin liner" or "binliner" is a slang term for a liner train carrying containers of waste for disposal.

Named freight trains

See also

References

Category:Commercial item transport and distribution Category:Freight equipment Category:Trains