Rail transport operations
Encyclopedia
A railway has two major components: the rolling stock
(the locomotives, passenger coaches, freight cars, etc.) and the infrastructure
(the permanent way, tracks, stations, freight facilities, viaducts, tunnels, etc.).
The operation of the railway is through a system of control, originally by mechanical means, but nowadays more usually electronic and computerized.
Fixed block signalling
Most blocks are 'fixed' blocks, i.e. they delineate a section of track between two defined points. On timetable, train order, and token-based systems, blocks usually start and end at selected stations. On signalling-based systems, blocks usually start and end at signals
. Alternatively, cab signalling
may be in use.
The lengths of blocks are designed to allow trains to operate as frequently as necessary. A lightly used branch line might have blocks many kilometres long, whilst a busy commuter railway might have blocks a few hundred metres long.
Moving block signalling
A disadvantage of fixed blocks is that the faster trains are permitted to run, the longer the stopping distance, and therefore the longer the blocks need to be. This decreases a line's capacity.
With moving block, computers are used to calculate a 'safe zone', behind each moving train, which no other train may enter. The system depends on precise knowledge of where each train is and how fast it is moving. With moving block, lineside signals are not provided, and instructions are passed direct to the trains. It has the advantage of increasing track capacity by allowing trains to run much closer together.
, rapid transit
and light rail
systems are isolated from the national system in the cities they serve. Some freight lines serving mines are also isolated, and these are usually owned by the mine company. An industrial railway
is a specialized rail system used inside factories or mines. Mountain railway
s are usually isolated, with special safety systems.
by one or more locomotive
units. Two or more locomotives coupled
in multiple traction are frequently used in freight trains. Railroad cars or rolling stock
consist of passenger cars, freight cars, maintenance cars and in America
caboose
s. Modern passenger trains sometimes are pushed/pulled by a tail and head unit (see top and tail
), of which not both need to be motorised or running. Many passenger trains consist of multiple unit
s with motors mounted beneath the passenger cars.
Most public transport
passenger operations happen in the train station
and in the passenger car. The passenger buys a ticket
, either in the station, or on the train (sometimes at a higher fare
). There are two ways of validating a ticket. In one case the passenger validates the ticket himself (by perforating it, for instance) and this is randomly checked by a ticket controller. A conductor
checks all persons on the train for valid tickets and devaluates them, so they cannot be used again. Some passenger cars, especially in long distance high speed trains have a restaurant or bar. These need to be catered. In recent times, train catering has been diminished somewhat by vending machine
s in the train station or on the train.
When not in use, passenger cars are stored, maintained and repaired in coach yards.
terminals (also called container freight stations or freight terminals), and at customer locations (e.g. mines
, grain elevator
s, factories
). Intermodal freight transport uses standardized containers
, which are handled by crane
s. Along their routes, freight trains are routed through rail yard
s to sort cars and assemble trains for their final destinations, as well as for equipment maintenance, refueling, and crew changes. Within a freight yard, trains are composed in a classification yard
. Switcher
or shunter locomotives help the composing.
A unit train
(also called a block train), which carries a block of cars all of the same origin and destination, does not get sorted in a classification yard, but may stop in a freight yard for inspection, engine servicing and/or crew changes.
Combining freight and passenger operations on a single track with passing loop
s poses operational problems, because of the different demands of freight operators and public transport. In many smaller countries passenger operations are done during the day, while freight trains operate mostly during the night. Dedicated tracks have been assigned to some operations.
, locomotives are cleaned, repaired, etc. Decommissioned locomotives are sometimes used to heat passenger cars and defrost railroad switch
es in winter. After this period, locomotives (and other rail vehicles) are turned into scrap
or are left to rust in a train depot. Some end up in railway museum
s or are bought by railway preservation groups.
Steam locomotives are housed in a circular train depot, a roundhouse
that surrounds a turntable
.
Each transport system represents a contribution to a country's infrastructure
, and as such must make economic
sense or eventually close. From this, each has a particular role or roles. These may change with time but they affect the specifications of each particular system.
, including both the physical geography
(hills, valleys, etc.) and the human geography
(location of settlements). The rail transport system may in turn feedback into the human geography.
of a system must pass through the geography and geology
of its region. This may be flat or mountainous, may include obstacles such as water and mountains. These determine, in part, the intrinsic nature of the system. The slope at which trains run must also be calculated correctly. In this stage, it is decided where tunnel
s pass.
) may be founded by a railroad passing through. Historically, when a station has been built outside the town or city it is intended to serve, that town has expanded to include the station, or buildings (especially Inn
s) sprung up near the station. The existence of a station may increase the number of commuters
who live in a town or village and so cause it to become a dormitory town. The transcontinental railroad
was a large factor in American colonization of the Western frontier. China's railroad expansion into Tibet
may have similar consequences.
can play a large part in decisions about railways, such as the Beeching Axe
. In the UK
, building or rebuilding a railway usually requires an Act of Parliament
.
Rolling stock
Rolling stock comprises all the vehicles that move on a railway. It usually includes both powered and unpowered vehicles, for example locomotives, railroad cars, coaches and wagons...
(the locomotives, passenger coaches, freight cars, etc.) and the infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
(the permanent way, tracks, stations, freight facilities, viaducts, tunnels, etc.).
Operation
Signalling
Signalling systems used to control the movement of traffic may be either of fixed block or moving block variety.Fixed block signalling
Most blocks are 'fixed' blocks, i.e. they delineate a section of track between two defined points. On timetable, train order, and token-based systems, blocks usually start and end at selected stations. On signalling-based systems, blocks usually start and end at signals
Railway signal
A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal's indication and acts accordingly...
. Alternatively, cab signalling
Cab signalling
Cab signalling is a railway safety system that communicates track status information to the cab, crew compartment or driver's compartment of a locomotive, railcar or multiple unit, where the train driver or engine driver can see the information....
may be in use.
The lengths of blocks are designed to allow trains to operate as frequently as necessary. A lightly used branch line might have blocks many kilometres long, whilst a busy commuter railway might have blocks a few hundred metres long.
Moving block signalling
A disadvantage of fixed blocks is that the faster trains are permitted to run, the longer the stopping distance, and therefore the longer the blocks need to be. This decreases a line's capacity.
With moving block, computers are used to calculate a 'safe zone', behind each moving train, which no other train may enter. The system depends on precise knowledge of where each train is and how fast it is moving. With moving block, lineside signals are not provided, and instructions are passed direct to the trains. It has the advantage of increasing track capacity by allowing trains to run much closer together.
Types of rail system
Most rail systems serve a number of functions on the same track, carrying local, long distance and commuter passenger trains, and freight trains. The emphasis on each varies by country. Some urban rail transitUrban rail transit
Urban rail transit is an all-encompassing term for various types of local rail systems providing passenger service within and around urban or suburban areas...
, rapid transit
Rapid transit
A rapid transit, underground, subway, elevated railway, metro or metropolitan railway system is an electric passenger railway in an urban area with a high capacity and frequency, and grade separation from other traffic. Rapid transit systems are typically located either in underground tunnels or on...
and light rail
Light rail
Light rail or light rail transit is a form of urban rail public transportation that generally has a lower capacity and lower speed than heavy rail and metro systems, but higher capacity and higher speed than traditional street-running tram systems...
systems are isolated from the national system in the cities they serve. Some freight lines serving mines are also isolated, and these are usually owned by the mine company. An industrial railway
Industrial railway
An industrial railway is a type of railway that is not available for public transportation and is used exclusively to serve a particular industrial, logistics or military site...
is a specialized rail system used inside factories or mines. Mountain railway
Mountain railway
A mountain railway is a railway that ascends and descends a mountain slope that has a steep grade. Such railways can use a number of different technologies to overcome the steepness of the grade...
s are usually isolated, with special safety systems.
Permanent way and railroad construction
The permanent way trails through the physical geography. The tracks' geometry is limited by the physical geography.Types of vehicle
Trains are pushed/pulledPush-pull train
Push–pull is a mode of operation for locomotive-hauled trains allowing them to be driven from either end.A push–pull train has a locomotive at one end of the train, connected via some form of remote control, such as multiple-unit train control, to a vehicle equipped with a control cab at the other...
by one or more locomotive
Locomotive
A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...
units. Two or more locomotives coupled
Coupling (railway)
A coupling is a mechanism for connecting rolling stock in a train. The design of the coupler is standard, and is almost as important as the railway gauge, since flexibility and convenience are maximised if all rolling stock can be coupled together.The equipment that connects the couplings to the...
in multiple traction are frequently used in freight trains. Railroad cars or rolling stock
Rolling stock
Rolling stock comprises all the vehicles that move on a railway. It usually includes both powered and unpowered vehicles, for example locomotives, railroad cars, coaches and wagons...
consist of passenger cars, freight cars, maintenance cars and in America
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
caboose
Caboose
A caboose is a manned North American rail transport vehicle coupled at the end of a freight train. Although cabooses were once used on nearly every freight train, their use has declined and they are seldom seen on trains, except on locals and smaller railroads.-Function:The caboose provided the...
s. Modern passenger trains sometimes are pushed/pulled by a tail and head unit (see top and tail
Top and tail
A top-and-tail railway train has locomotives at both ends, for ease of changing direction. This is a British term. It is normal for only the leading locomotive to power the train when in top-and-tail mode, cf push pull operation with both locomotives powering.It is properly distinct from a...
), of which not both need to be motorised or running. Many passenger trains consist of multiple unit
Multiple unit
The term multiple unit or MU is used to describe a self-propelled carriages capable of coupling with other units of the same or similar type and still being controlled from one driving cab. The term is commonly used to denote passenger trainsets consisting of more than one carriage...
s with motors mounted beneath the passenger cars.
Passenger operations
Public transport
Public transport is a shared passenger transportation service which is available for use by the general public, as distinct from modes such as taxicab, car pooling or hired buses which are not shared by strangers without private arrangement.Public transport modes include buses, trolleybuses, trams...
passenger operations happen in the train station
Train station
A train station, also called a railroad station or railway station and often shortened to just station,"Station" is commonly understood to mean "train station" unless otherwise qualified. This is evident from dictionary entries e.g...
and in the passenger car. The passenger buys a ticket
Ticket (admission)
A ticket is a voucher that indicates that one has paid for admission to an event or establishment such as a theatre, movie theater, amusement park, zoo, museum, concert, or other attraction, or permission to travel on a vehicle such as an airliner, train, bus, or boat, typically because one has...
, either in the station, or on the train (sometimes at a higher fare
Fare
A fare is the fee paid by a passenger allowing him or her to make use of a public transport system: rail, bus, taxi, etc. In the case of air transport, the term airfare is often used.-Uses:...
). There are two ways of validating a ticket. In one case the passenger validates the ticket himself (by perforating it, for instance) and this is randomly checked by a ticket controller. A conductor
Conductor (transportation)
A conductor is a member of a railway train's crew that is responsible for operational and safety duties that do not involve the actual operation of the train. The title of conductor is most associated with railway operations in North America, but the role of conductor is common to railways...
checks all persons on the train for valid tickets and devaluates them, so they cannot be used again. Some passenger cars, especially in long distance high speed trains have a restaurant or bar. These need to be catered. In recent times, train catering has been diminished somewhat by vending machine
Vending machine
A vending machine is a machine which dispenses items such as snacks, beverages, alcohol, cigarettes, lottery tickets, consumer products and even gold and gems to customers automatically, after the customer inserts currency or credit into the machine....
s in the train station or on the train.
When not in use, passenger cars are stored, maintained and repaired in coach yards.
Freight operations
Freight or cargo trains are loaded and unloaded in intermodalIntermodal freight transport
Intermodal freight transport involves the transportation of freight in an intermodal container or vehicle, using multiple modes of transportation , without any handling of the freight itself when changing modes. The method reduces cargo handling, and so improves security, reduces damages and...
terminals (also called container freight stations or freight terminals), and at customer locations (e.g. mines
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
, grain elevator
Grain elevator
A grain elevator is a tower containing a bucket elevator, which scoops up, elevates, and then uses gravity to deposit grain in a silo or other storage facility...
s, factories
Factory
A factory or manufacturing plant is an industrial building where laborers manufacture goods or supervise machines processing one product into another. Most modern factories have large warehouses or warehouse-like facilities that contain heavy equipment used for assembly line production...
). Intermodal freight transport uses standardized containers
Containerization
Containerization is a system of freight transport based on a range of steel intermodal containers...
, which are handled by crane
Crane (machine)
A crane is a type of machine, generally equipped with a hoist, wire ropes or chains, and sheaves, that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of...
s. Along their routes, freight trains are routed through rail yard
Rail yard
A rail yard, or railroad yard, is a complex series of railroad tracks for storing, sorting, or loading/unloading, railroad cars and/or locomotives. Railroad yards have many tracks in parallel for keeping rolling stock stored off the mainline, so that they do not obstruct the flow of traffic....
s to sort cars and assemble trains for their final destinations, as well as for equipment maintenance, refueling, and crew changes. Within a freight yard, trains are composed in a classification yard
Classification yard
A classification yard or marshalling yard is a railroad yard found at some freight train stations, used to separate railroad cars on to one of several tracks. First the cars are taken to a track, sometimes called a lead or a drill...
. Switcher
Switcher
A switcher or shunter is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been...
or shunter locomotives help the composing.
A unit train
Unit train
A unit train, also called a block train, is a railway train in which all the cars making it up are shipped from the same origin to the same destination, without being split up or stored en route...
(also called a block train), which carries a block of cars all of the same origin and destination, does not get sorted in a classification yard, but may stop in a freight yard for inspection, engine servicing and/or crew changes.
Combining freight and passenger operations on a single track with passing loop
Passing loop
A passing loop is a place on a single line railway or tramway, often located at a station, where trains or trams in opposing directions can pass each other. Trains/trams in the same direction can also overtake, providing that the signalling arrangement allows it...
s poses operational problems, because of the different demands of freight operators and public transport. In many smaller countries passenger operations are done during the day, while freight trains operate mostly during the night. Dedicated tracks have been assigned to some operations.
Locomotive operations
When inactive, locomotives are housed in a locomotive depot (UK term) or engine house (US). In engine facilities, or a Traction Maintenance DepotTraction maintenance depot
In the United Kingdom, a traction maintenance depot, or TMD, is a railway depot where locomotives are serviced and maintained. A traction and rolling stock maintenance depot, or T&RSMD, is a maintenance depot where locomotives, multiple units and rolling stock are serviced and maintained. Each rail...
, locomotives are cleaned, repaired, etc. Decommissioned locomotives are sometimes used to heat passenger cars and defrost railroad switch
Railroad switch
A railroad switch, turnout or [set of] points is a mechanical installation enabling railway trains to be guided from one track to another at a railway junction....
es in winter. After this period, locomotives (and other rail vehicles) are turned into scrap
Scrap
Scrap is a term used to describe recyclable and other materials left over from every manner of product consumption, such as parts of vehicles, building supplies, and surplus materials. Unlike waste, scrap has significant monetary value...
or are left to rust in a train depot. Some end up in railway museum
Railway museum
A railway museum is a museum that explores the history of all aspects of rail related transportation, including: locomotives , railway cars, trams, and railway signalling equipment.See List of railway museums...
s or are bought by railway preservation groups.
Steam locomotives are housed in a circular train depot, a roundhouse
Roundhouse
A roundhouse is a building used by railroads for servicing locomotives. Roundhouses are large, circular or semicircular structures that were traditionally located surrounding or adjacent to turntables...
that surrounds a turntable
Turntable (railroad)
A railway turntable is a device for turning railroad rolling stock. When steam locomotives were still in wide use, many railroads needed a way to turn the locomotives around for return trips as their controls were often not configured for extended periods of running in reverse and in many...
.
Maintenance of way operations
The presence of a work train on a given section of track will temporarily decrease the capacity of the route. The normal method in such operations is to cease other traffic altogether during the track 'occupation'. Services may be diverted by an alternative route, if available; alternatively, passenger services may be maintained using a replacement bus service. It is therefore more economically viable to plan such track occupations for periods of reduced usage (e.g. 'off-peak', overnight or holiday times) to minimise the impact on normal services and revenue.Background factors (feasibility)
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
, and as such must make economic
Economy
An economy consists of the economic system of a country or other area; the labor, capital and land resources; and the manufacturing, trade, distribution, and consumption of goods and services of that area...
sense or eventually close. From this, each has a particular role or roles. These may change with time but they affect the specifications of each particular system.
Extrinsic factors
Rail transport systems are built into the landscapeLandscape
Landscape comprises the visible features of an area of land, including the physical elements of landforms such as mountains, hills, water bodies such as rivers, lakes, ponds and the sea, living elements of land cover including indigenous vegetation, human elements including different forms of...
, including both the physical geography
Physical geography
Physical geography is one of the two major subfields of geography. Physical geography is that branch of natural science which deals with the study of processes and patterns in the natural environment like the atmosphere, biosphere and geosphere, as opposed to the cultural or built environment, the...
(hills, valleys, etc.) and the human geography
Human geography
Human geography is one of the two major sub-fields of the discipline of geography. Human geography is the study of the world, its people, communities, and cultures. Human geography differs from physical geography mainly in that it has a greater focus on studying human activities and is more...
(location of settlements). The rail transport system may in turn feedback into the human geography.
Physical geography
The permanent wayPermanent way
The permanent way is the elements of railway lines: generally the pairs of rails typically laid on the sleepers embedded in ballast, intended to carry the ordinary trains of a railway...
of a system must pass through the geography and geology
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
of its region. This may be flat or mountainous, may include obstacles such as water and mountains. These determine, in part, the intrinsic nature of the system. The slope at which trains run must also be calculated correctly. In this stage, it is decided where tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...
s pass.
Human geography
Rail transport systems affect the human geography. Large cities (such as NairobiNairobi
Nairobi is the capital and largest city of Kenya. The city and its surrounding area also forms the Nairobi County. The name "Nairobi" comes from the Maasai phrase Enkare Nyirobi, which translates to "the place of cool waters". However, it is popularly known as the "Green City in the Sun" and is...
) may be founded by a railroad passing through. Historically, when a station has been built outside the town or city it is intended to serve, that town has expanded to include the station, or buildings (especially Inn
INN
InterNetNews is a Usenet news server package, originally released by Rich Salz in 1991, and presented at the Summer 1992 USENIX conference in San Antonio, Texas...
s) sprung up near the station. The existence of a station may increase the number of commuters
Commuting
Commuting is regular travel between one's place of residence and place of work or full time study. It sometimes refers to any regular or often repeated traveling between locations when not work related.- History :...
who live in a town or village and so cause it to become a dormitory town. The transcontinental railroad
First Transcontinental Railroad
The First Transcontinental Railroad was a railroad line built in the United States of America between 1863 and 1869 by the Central Pacific Railroad of California and the Union Pacific Railroad that connected its statutory Eastern terminus at Council Bluffs, Iowa/Omaha, Nebraska The First...
was a large factor in American colonization of the Western frontier. China's railroad expansion into Tibet
Tibet
Tibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...
may have similar consequences.
Historical factors
Rail transport systems are often used for purposes they were not designed for, but have evolved into due to changes in human geography. PoliticsPolitics
Politics is a process by which groups of people make collective decisions. The term is generally applied to the art or science of running governmental or state affairs, including behavior within civil governments, but also applies to institutions, fields, and special interest groups such as the...
can play a large part in decisions about railways, such as the Beeching Axe
Beeching Axe
The Beeching Axe or the Beeching Cuts are informal names for the British Government's attempt in the 1960s to reduce the cost of running British Railways, the nationalised railway system in the United Kingdom. The name is that of the main author of The Reshaping of British Railways, Dr Richard...
. In the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, building or rebuilding a railway usually requires an Act of Parliament
Act of Parliament
An Act of Parliament is a statute enacted as primary legislation by a national or sub-national parliament. In the Republic of Ireland the term Act of the Oireachtas is used, and in the United States the term Act of Congress is used.In Commonwealth countries, the term is used both in a narrow...
.