Rail terminology is a form of technical terminology. The difference between the American term railroad and the international term railway (used by the International Union of Railways and English-speaking countries outside the US) is the most obvious difference in rail terminology (see usage of the terms railroad and railway for more information). There are also others, due to the parallel development of rail transport systems in different parts of the world.
Various terms are presented here alphabetically; where a term has multiple names, this is indicated. The note "US" indicates a term peculiar to North America, or "CA" may represent Canada while "UK" refers to terms originating in the British Isles and normally also used in former British colonies outside North America (such as Australia "AU", New Zealand "NZ", etc.). The abbreviation "UIC" refers to standard terms adopted by the International Union of Railways in its official publications and Thesaurus.
Exceptions are noted; terms whose currency is limited to one particular country, region, or railway are also included.
Similar to the Dead man's switch other than it does not require the operator's constant interaction. Instead, an alarm is sounded at a preset interval in which the operator must respond by pressing a button to reset the alarm and timer if no other controls are operated. If the operator does not respond within a preset time, the prime mover is automatically throttled back to idle and the brakes are automatically applied. May also be called a 'Watchdog'.
A large key which locks levers or other items of signalling apparatus, serving as a portable form of interlocking. With the key removed from the lock, the lever or apparatus is locked in its position. When the key is turned in the lock, it cannot be removed.
A branch line train consisting of a steam locomotive and passenger carriages that can be driven from either end by means of rodding to the regulator and an additional vacuum brake valve. The fireman remains with the locomotive and, when the driver is at the other end, the fireman controls the cut off and vacuum ejectors in addition to his usual duties. Also : Push-pull train, Motor train (UK).
A looped length of track, usually at the end of a spur or branch, which allows trains to turn around for the return trip without reversing or shunting. Can be used as part of a freight installation to allow the loading or unloading of bulk materials without the need to stop the train (see merry-go-round train (MGR)).
An iron or steel plate used to spread the weight of rail over a larger area of sleeper (tie) and facilitate a secure, low maintenance, fastening with bolts or clips. It derives from the former rail chairs.
A train crew member who performs railcar and track management; often a single job description along with switchman ("brakeman/switchman"). A brakeman manually activated brakes on railroad cars before the advent of air brakes.
A heavy vehicle with powerful brakes which was attached to the rear of goods trains in the days when most wagons were not fitted with a continuous braking system. Its function was to supplement the locomotive's braking power in slowing and stopping the train and to keep the couplings uniformly tight by selective light braking to avoid snatching and breakages. It also conveyed the train guard, hence its alternative name of "guards van". Partly analogous to caboose and its synonyms.
Track where the rails are spaced more widely apart than 1,435 mm (4 ft 81⁄2 in) (which is called standard gauge). Many early railroads were broad gauge, for example the Great Western Railway in the UK which adopted 7 ft (2,134 mm) gauge until it was converted to standard gauge in the 1860s - 1890s. Russia still has over 80,000 km (50,000 mi) of broad gauge (1,520 mm (4 ft 1127⁄32 in)) railroads. Broad gauge is also normal in Spain and Portugal (1,668 mm (5 ft 521⁄32 in) Iberian gauge), in India (1,676 mm (5 ft 6 in) Indian gauge), as well as Ireland and used in some parts of Australia (1,600 mm (5 ft 3 in) Irish gauge).
A steel rail section commonly used in 60 ft lengths on almost all railway lines throughout Britain until c1950, which due to its shape must be supported in cast iron chairs that are screwed to the sleepers. It is still found on some London Underground lines, on secondary and preserved lines and in yards. The rail has two heads (shaped somewhat like a vertical dumbbell) which led some people to assume that when one side became worn, the rail could be inverted and reinstalled for further service rather than being replaced (it can't, because the two heads are different sizes, and by the time the top became worn down sufficiently to fit in the chairs when the rail is inverted, both the top and the bottom of the rail would be too small for further use).
The practice of replacing train service, whether light rail, tram/streetcar systems, or full-size railway systems, with a bus service, either on a temporary or permanent basis. Somewhat derogatory and mainly used in the UK, Canada, USA, and Australia. The word is a portmanteau of the words "bus" and "substitution".
Typically refers to a steam locomotive with its cab at the leading end of the boiler, rather than the usual trailing end adjacent to the tender. The best known example is the Southern Pacific Railroad's AC type, built to handle drag freights through the SP's many tunnels and snow sheds without the danger of the exhaust asphyxiating the engine crew.
A railroad car attached usually to the end of a train, in which railroad workers could ride and monitor track and rolling stock conditions. Partly analogous to brake van (UK). Largely obsolete, having been replaced by the electronic End of Train (EOT) device, or Flashing Rear End Device called "FRED".
A train consisting of only a locomotive and a caboose.
Synonymous with superelevation : Angle. Can be used in the context of the cant of the track (the relative level one rail to another, e.g. on curves) (UK); and the cant of a rail, being the angle of an individual rail relative to vertical.
Reciprocating, oscillating or rotating body which imparts motion to another body known it is in contact.
A shaft which carries a series of cams for operating the inlet valves and exhaust valves of a diesel engine, and contactors in some electric traction control gear systems.
An auxiliary steam locomotive tender which carries extra water on long journeys.
To note the cancellation of a passenger train service to employees. (From British Railways telegraphic codeword)
A heavier duty locomotive with 6 wheels per bogie (all axles being separately driven) configuration as opposed to a 4-wheel "Bo-Bo" configuration. The correct classification is Co'Co', but Co-Co is used more often.
A steam-operated device in the tender intended to push coal forward to a point where it can be shovelled directly into the fire.
A signaling system that uses both colour and light position to determine the meaning of the aspect shown.
Combined power handle
A handle or lever which controls both the throttle and the dynamic braking on the locomotive : on a desktop-type control stand, forward (away from operator) past center operates the dynamic brake, backward (toward operator), past center, is throttle up.
A passenger car with more than one class of accommodation provided, e.g. First and Third. In earlier days of three-class travel, First and Second class, and Second and Third class composites were also built. A car with First, Second and Third classes was also known as a tri-composite.
The person "in charge" of a train and its crew. On passenger trains, a conductor is also responsible for tasks such as assisting passengers and collecting tickets. In Australia, both terms are used, "conductor" for the person checking tickets, etc. on a tram or train, and "guard" for the person in charge of the train.
Rods between crank pins on the wheels, transferring power from a driving axle to a driven axle of a locomotive.
Cow and calf
A diesel locomotive with a crew cab permanently coupled to and acting as a controller for a similar slave diesel locomotive without a crew cab, primarily used for switching/shunting duties for large groups of rolling stock. Also known as master and slave, as in the British Rail Class 13 shunters at Tinsley Marshalling Yard. (Cow can also refer, in S&C, to the units relaying ground wiring to signaling units)
A variable device on steam locomotives which closes the steam valve to the steam cylinder before the end of the piston stroke, thus conserving steam while allowing the steam in the cylinder to expand under its own energy. See also: Reverser handle.
A channel dug through a hillside to enable rail track to maintain a shallow gradient. See also embankment
Making repeated service brake reductions in short succession to maintain a constant speed on short but steep grades. Each reduction must be at least 5 psi lower than the previous one in order to keep the brakes applying regularly, but excessive cycle braking can deplete the air supply and require an emergency application.
The central working part of a reciprocating engine, the space in which a piston travels.
On steam locomotives, this appurtenance allows condensed water to be drained from the steam cylinders when the throttle is opened, thus preventing damage to the pistons, running gear, and cylinder heads.
A block signal that is displaying no discernible aspect, often due to burned out lamps or local power failure. Most railroads require that a dark signal be treated as displaying its most restrictive aspect, e.g., stop and stay for an absolute signal.
A safety mechanism on a train controller which automatically applies the brake if a lever is released. It is intended to stop a train if the driver is incapacitated. In some forms, this device may be pedal-actuated.
A set of diesel-powered self-propelling passenger rail vehicles able to operate in multiple with other such sets. Such units, especially those consisting of a single vehicle, are sometimes termed railcars.
A practice employed to move large trains through the mountains. Consists of the locomotives on the head end, a "swing" (mid-train) helper or two, and pusher locomotive(s) on the rear; today, all units are remotely controlled by the engineer in the lead unit. The power distribution alleviates stress on the couplers and relieves the lead units of the full weight of the train, making it easier to move on grades.
Gasoline-electric self-powered passenger car used for small capacity rural commuter service. Also a British Rail Class 153 DMU.
Double, as in "Double the hill"
if a train has insufficient power to climb a grade and no helpers are available, the train will be split into two sections and run separately to the top.
Doubleheading or Doubleheader (US)
In which two steam locomotives are coupled head-to-tail in order to haul a heavy train up a long or steep hill. In the present day, doubleheaders (and occasionally tripleheaders) are done primarily on large passenger trains or as a show for railfans.
(UK) A direction (usually away from London, other capital city, or the headquarters of the railway concerned) or side (on left-running railways, the left side when facing in the down direction). The opposite of up. The down direction is usually associated with odd-numbered trains and signals. In Australia it is used relative to the state's capital city. US railways use the compass points northbound, southbound, eastbound and westbound.
The part of a coupler that attaches to the frame of the car or locomotive; may be equipped with a pneumatic cushion depending on a freight car's design cargo, e.g. an autorack. Alternately, the pinned double bars coupling a steam locomotive to its tender.
A class of control cars used in the UK. (See also : DBSO - predecessor to the DVT)
abbr. Designated Supervisor of Locomotive Engineers.
A signal light that is considerably smaller and closer to the ground than a high-mast signal; often absolute, and placed within interlocking limits, its aspects tend to differ from those conveyed by a taller signal for certain indications. Also called 'pot' or 'jack'.
Component of vacuum brake system. Steam passing through a cone sucks air from the train pipe to create the vacuum. Usually fitted in pairs : A small ejector running continuously to overcome leaks and to restore the vacuum after light braking and a large ejector operated when needed to release the brakes quickly after a heavy application or to create the initial vacuum ("making a brake" – UK) after coupling up.
Railfan jargon to describe how multiple locomotives are coupled together in a train; the front of the second locomotive is coupled to the rear of the first locomotive, the front of the third locomotive is coupled to the rear of the second locomotive, and so on down the line. The term is reminiscent of a parade of circus elephants where the elephant behind the front elephant would hold the leading elephant's tail in its trunk.
One typically built on supports over city streets, commonly called "the el" or simply the "The L".
A raised pathway on which rail tracks are placed to maintain a shallow gradient when passing over depressions in the terrain. See also cutting.
Empty Coaching Stock train, or ECS
A train used to bring carriages into (or out of) service. They usually run between sidings and main stations, with the carriages then forming a service train to another destination. They are often worked under freight train rules - e.g. without needing a guard in the UK.
A device that continuously captures analog and digital train systems information and stores that data for a minimum of 48 hours. This data is used to evaluate incidents and accidents. Typical stored data includes speed, brake pressure, dynamic brake, horn activation, track signal, etc. In the U.S., event recorders are mandated by the Federal Railroad Administration (FRA) for freight, passenger and commuter rail. Regulations for railroad outside the U.S. vary by country. Transit operations are not generally required to have event recorders, but have begun to add them voluntarily.
An ex-Conrail locomotive (jargon) or former employee of Conrail. Not to be confused with the more common meaning of a convicted criminal who has been released after serving prison time.
A train that passes selected stations without stopping.
A train not included in the normal schedule of a railroad. They often run during busy holiday travel periods in order to handle larger crowds and reduce the number of passengers that are forced to stand or are stranded at a station. In train order territory, extras are required to clear the main line for scheduled trains to pass.
A heavy, hinged steel plate attached in a horizontal position to the rear of the locomotive footplate or front of a locomotive tender. When the tender is attached to its locomotive the plate is allowed to fall to cover the gap in the "floor" between the two units. The sliding edge is not fixed and has a smooth chamfer so as to avoid a trip hazard.
In steam railroading, a firebox was a chamber in which a fire would produce sufficient heat to create steam once the hot gases from the firebox were carried into the adjacent boiler via tubes or flues.
A metal plate that joins the ends of rails in jointed track.
A wheel defect where the tread of a wheel has a flat spot and is no longer round; flats can be heard as regular clicking or banging noises when the wheel passes by. This is caused either by a locked bearing, or a brake that was not fully released before the car was moved, dragging the wheel without turning.
A type of rolling stock, which can be a flat-bottomed car with no sides on which freight (including intermodal containers) can be stacked. A bulkhead is a flatcar with walls on the front and rear. A center-beam bulkhead is a bulkhead flatcar with an additional wall dividing one side of the flatcar from the other, but still without any sides. Flat wagon (UIC, UK).
A railway junction that has a track configuration in which merging or crossing railroad lines provide track connections with each other without requiring trains to cross over in front of opposing traffic.
Flying switch (US)
Fly shunting (UK) : The practice of uncoupling a locomotive from a car in motion and running over a switch, whereupon an employee on the ground lines the switch to divert the car onto an adjacent track. Once commonplace, this practice is now strictly prohibited due to the high risk to life and property.
A colloquial term for a railfan, specifically one whose enthusiasm is excessive, "foaming at the mouth".
The point of a switch turnout where a car or locomotive on one track will obstruct movement on the adjacent track.
A small marking device with a flashing red light mounted on the end of the train. FRED also monitors various train functions such as brake pipe pressure, motion and GPS location. A form of an electronic caboose. Also called an EOT (end of train) device.
A casting with "X" shaped grooves used in switches and crossovers.
Full service reduction
The maximum air pressure that can be exerted against brake pistons in a normal brake application. To increase pressure beyond this point, the brakes must be placed in emergency.
A Thomas the Tank Enginemisnomer for a chimney] (UK) or smokestack (US), although it is also used in Australia (Victoria at least). Some early steam engines had a smokestack consisting of a straight vertical flue and a funnel-shaped top, probably leading to the use of "funnel" to describe the entire stack.
A brakeman uses a fusee to demonstrate a hand signal indicating "stop"
A type of rolling stock with a flat bottom and relatively low sides, used to haul material such as ore or scrap, and loaded and unloaded from the top. May be covered or uncovered. Open wagon (UIC, UK).
A double rail section of track, sometimes found in train yards and on bridges to prevent derailments or limit damage caused by derailments, by having rail on both sides of the wheel flange. Also found on curves with a tight radius and switches and crossings
A small, hand-powered railroad car used for track inspection. Pump trolley (UK).
The condition of locomotives and cars swaying in opposite directions when traversing depressions on the roadbed. A potentially dangerous condition that can cause coupler damage, lading damage, or derailments at slower speeds.
A length of track feeding a number of sidings that permits the sidings to be shunted without blocking the main line, or where two lines merge into one before ending with a buffer, to allow a run-round procedure to take place.
A transverse structural member located at the extreme end of a rail vehicle's underframe. The headstock supports the coupling at that end of the vehicle, and may also support buffers, in which case it may also be known as a "buffer beam".
Heavy freight operations.
Heavy rail (US)
A city-based transit rail system that runs on its own dedicated track and often underground. Subways are considered heavy rail. Refers to commuter rail and inter-city rail when used by the FRA or in other countries.
During the period between about 1910 and the mid nineteen thirties, most passenger cars in the US were built with three axle trucks, concrete floors, and riveted, double walled sides and often weighed 90 - 100 tons or more. Heavyweight construction was used to improve ride quality.
1. The conductor's signal for a train to depart. 2. To move at speed over the main track on a clear signal indication. Originated with the now-obsolete ball signal system, in which a ball hoisted all the way to the top of its post indicated to a train crew that the track ahead was clear.
High cube (US)
A boxcar whose vertical clearance is excessive (see Plate).
A device attached to the track which monitors passing trains for hot axles, and then reports the results via a radio transmission (US) or a circuit to the signal box (UK). (see defect detector).
Hotel power (US)
Electric power used to provide for the comfort of passengers aboard a train en route. See "HEP" above.
Hot rail (US)
1. Any section of track over which a train movement is imminent. The closer and/or faster the approaching train, the "hotter" the rail. 2. On some electrified railroads and rapid transit lines, the third rail which supplies power to locomotives or cars.
A fast, long-distance train given priority on the track over other trains.
A raised section in a rail sorting yard that allows operators to use gravity to move freight railcars into the proper position within the yard when making up trains of cars (that is, humping the cars). This is faster and requires less effort than moving cars with a switching engine.
Swaying motion of a railway vehicle or bogie caused by the coning action on which the directional stability of an adhesion railway depends. The truck or bogie wanders from side to side between the rails, "hunting" for the optimum location based on the forces at play.
Any location that includes a switch or crossing of two tracks, derived from the early practice of installation of a system of mechanical equipment called an interlocking plant to prevent collisions. See also signal box. Interlocking is also the term for the actual mechanical or electrical apparatus that prevents switch/points and signals from being operated in ways that would allow for conflicting train movements.
Intermodal ship-to-rail transfer of containerized cargos at APM Terminals in Portsmouth, VA. Also see TOFC.
Moving goods by more than one type of vehicle. Intermodal freight can be transported using shipping containers which can easily be transferred among railroad flatcars, ships, airplanes, and tractor-trailer trucks.
To break a train in two, usually by shearing the knuckle pin in a coupler, often caused by the application of excessive head end power at startup. Example : "The engineer jerked a lung on the upgrade." Also : Get a knuckle.
To shove a car a short distance and uncouple it in motion, allowing it to roll free under gravity and/or its own inertia onto a track. Commonly practiced in bowl or hump yards to make up or break down trains or classify large numbers of cars in an expedient fashion. Differs from a flying switch (see) in that the locomotive is pushing the car rather than pulling it when the cut is made.
A freight car with a defect in its brake valve that causes the entire train's brake system to go into emergency when any application is made.
Kinematic envelope (KE)
The outline of the space beside and above the track that must be kept clear of obstructions for the train to pass. This can be larger than the static clearance around an unmoving engine or car.
Knock down (US)
To pass an absolute signal and thereby change its aspect to stop; originated in the days of semaphore signals whose arms would drop to the stop aspect when passed.
The articulating part of a coupler that locks automatically in its closed position to join rail cars; so named because its movement resembles that of the human finger.
A crossing on one level ("at-grade intersection") – without recourse to a bridge or tunnel – generally of a railway line by a road or path (also called a railroad crossing, railway crossing, train crossing or grade crossing (US)). The term is sometimes used for a crossing by (not a junction with) another rail track (known as a flat crossing in the UK).
A city-based rail system based on tram design standards that operates mostly in private rights-of-way separated from other traffic but sometimes, if necessary, mixed with other traffic in city streets. Light rail vehicles (LRV) generally have a top speed of around 55 mph (89 km/h) though mostly operating at much lower speeds, more akin to road vehicles. Light rail vehicles usually run on trackage that weighs less per foot (due to a smaller track profile) than the tracks used for main-line freight trains; thus they are "light rail" due to the smaller rails usually used.
An obsolete method of coupling rail cars, consisting of manually dropping the coupling pin into the drawbar as the cars joined. Extremely hazardous to the brakemen of its day, it was outlawed by the Railroad Safety Appliance Act of 1893.
A train that stops at most, if not all, stations along its route. Often referred to in North America as a "milk train" or "milk run" (usage from the days when trains stopped at every station and stop along their route to pick up fresh milk brought to the stations daily from local dairy farms).
Location case (UK)
A trackside cabinet used to house signalling equipment such as relays or transformers.
Used on single-track railway lines, a loop is a second parallel track (running for a short distance), allowing two trains to pass by one another.
An off-white color of Railway signal light, like the Moon, achieved by the use of a clear lens of very light blue, to make it distinct from a light that has a broken lens. In UK practice, it is the color used for the type of junction indicator known as a feather, so-called for its resemblance to a popular inn sign.
In a diesel-electric locomotive, the main generator is coupled directly to the prime mover and its sole purpose is to feed electrical energy to the traction motors (an auxiliary generator powers lights and electrical appliances in the cab).
Generally seen as the abbreviation MU, this normally refers to the ability of diesel and electric locomotives or multiple units to be joined together and controlled from one driving station. Such a set of joined locomotives is called (US) a consist or (colloquially) "lash-up" and is said to be "MUed together".
Railroad track where the rails are spaced less than 1,435 mm (4 ft 81⁄2 in) apart. There are many common gauges narrower than standard, amongst them 3 ft 6 in (1,067 mm) widely in Africa and Asia; 3 ft (914 mm), which was the most common narrow gauge in the U.S.; 2 ft 6 in (762 mm), used in various locations across Europe, Asia and elsewhwere, South America and Australia, and 2 ft (610 mm), which saw widespread use in the UK. Meter gauge 1,000 mm (3 ft 33⁄8 in) is also widely used in Asia and Africa. Narrow-gauge lines are often found in mountainous terrain where the cost savings of building a smaller railroad can be considerable. (Historically, the term "narrow gauge" was once used in Britain for what is now called standard gauge, as the only other gauge then in common use was the Great Western Railway's 7 ft (2,134 mm) broad gauge.)
When equipment is placed ahead of the fouling point of a switch turnout.
A bridge over the railway.
A distance (normally 180 metres or set according to the permitted speed of the line) beyond a stop signal which must be clear before the preceding stop signal can display a proceed aspect; allows a margin in case a train overshoots a signal before stopping.
A fee paid by a rail company to the owner of a car (or wagon) for the time it spends on the company's property; also an authorized living expense payment for some workers forced away from their home terminal. Pronounced by some U.S. railroaders per die-um, not per dee-um.
A block signal whose most restrictive indication is stop and proceed. A permissive signal is identified by the presence of a number plate affixed to the mast or supporting structure. Proceeding beyond a permissive signal at stop is allowed at restricted speed if operating conditions enable a train operator to stop before reaching any train or obstruction.
Person in charge of possession (PICOP) (UK)
The railway or contractor's official responsible for safe working during engineer's possession
1. A deflective shield affixed to the front of a locomotive to protect its wheels from on-track debris; archaically called a "cowcatcher." 2. An employee qualified on the operating rules and physical characteristics of a certain section of the railroad, assisting a crew who is not so qualified.
Where it is necessary to temporarily work a section of line as single track (for instance if the other track of a double track line is out of use), a person (the Pilot man) acts as the single track token.
A Porter had various roles : A Baggage Porter assisted with luggage; an Operating Porter assisted with Safeworking duties; a Station Porter assisted with general station duties and a Lad Porter was a junior Station Porter.
Term describing the weight (and thus the cross section) of a length of rail. A heavier rail can carry heavier loads with less distortion and less damage to the rails themselves and the roadbed.
A locomotive or group of connected (MU'd) locomotives serving as the motive power for a train (as in "the hostler brought the power to the service pit.")
Pulling against the train brakes at the higher end of the locomotive's power output (e.g. notches 5 through 8 on a conventional throttle); this is considered wasteful of fuel and brake shoes, and is therefore discouraged by most operating departments.
The internal combustion engine of a diesel locomotive.
A rail broken from cold-related contraction.
A push pole
A pole about 12 feet (366 cm) long and having a diameter of 5 inches (127 mm). They were placed in receptacles called push pole pockets. The pole was placed between the locomotive and the freight car, and used to push the car on or off a siding or to another track. Used between 1870 and the mid-1960s.
A mode of operation whereby a locomotive-hauled train may be driven with the locomotive at the front, middle or back of the train. Also : Auto train (UK), above. See Top and tail for train with locomotives at both front and back.
Also quarterly or periodic inspection, a federally mandated safety inspection performed on a locomotive every 92 operating days.
Quiet Zone (US)
A designation by the Federal Railroad Administration that removes the requirement for train operators to sound their horn when approaching each public crossing in a certain area, often near residential neighborhoods who have asked for the status. Because the train does not sound its horn while approaching the crossings, safety upgrades to all of the crossings must be made in order to compensate. These upgrades usually include double gates, additional signage, lights, and bells, if they are not already present. Additionally, the residents requesting the status must indemnify the railroad from any resulting crossing mishaps.
A passenger rail vehicle (typically non-articulated or rigid frame) that was derived from bus propulsion and construction technology, but which may evolve into larger dimensions, performance and characteristics similar in appearance to a light DMU Railcar
The cross section shape of rail. There are many rail profiles which are often specific to individual railroads. Rails need to be periodically scanned electronically, the data inspected and analysed, then re-profiled with rail grinding machines to maintain the safe and proper "rail profile". Rails that cannot be brought back to the proper rail profile are condemned and replaced.
A colour generally associated with stop, when shown by signals or flags.
The area between, under, or within a few feet of cars and locomotives; to enter the zone, a ground employee must obtain protection from the locomotive engineer (if a locomotive is coupled) or a blue signal (if no locomotive is coupled).
The practice of detaching a locomotive from its train, driving it to the other end of the train and re-attaching it, to allow the train to proceed in the direction it has just come from (e.g. when it reaches its destination and forms a service in the other direction). (See headshunt for diagram of a 'run-round loop'.)
Locomotives that remain attached to a manifest or unit train from their home rails over the tracks of a receiving railroad until the train reaches its final destination.
A container on locomotives and self-propelled multiple units, or trams, that run on tramways and adhesion railways. The container holds sand which can be dropped onto the rail to improve rail adhesion under wet, steep or slippery rail conditions. The sandbox and operating mechanism are collectively known as 'sanding gear'.
A section of track off the main line. Sidings are often used for storing rolling stock or freight. A siding is also used as a form of rail access for warehouses and other businesses, where the siding will often meet up with loading docks at rail car height in the building. In the U.S. the term is also used to cover the British term : loop. Also, a passing track in the U.S.
A person in charge of the signalling at a station or junction, often in a Signal-box.
The narrow corridor between a pair of closely spaced tracks, nominally six feet wide. See also four-foot and ten-foot.
A temporary speed restriction to protect, for example, sections of track in poor condition and awaiting repair. Also applies to the timing tolerance included in timetable schedules to allow for such restrictions.
Bars placed at 90° to the rail tracks to support the rails. Generally of wood, concrete or steel, with hardware to affix the rails, usually spikes, nails or bolts. Note in the UK baseplates and clips are used to affix the rail to the sleeper. Spikes are widely used in North America.
Slip coach (UK)
A passenger coach that is disconnected from a train without the train havin to stop. While the train continued on its route, the slip coach would be guided and stopped by a guard on board using the coach's own brake mechanism. This practice was almost entirely limited to the United Kingdom and was discontinued in the 1960s.
A local speed restriction below the track's normal speed limit often designated by yellow and green flags. Slow orders can be imposed on a temporary basis to protect, for example, maintenance of way employees while sections of track are under repair. Widely used in areas where track is substandard and in need of repair.
An enclosed (normally cylindrical) space attached to the end of the boiler opposite the firebox on a steam locomotive (normally the front). Supports the stack/chimney; steam pipes to and from the cylinders pass through here; contains the blastpipe/exhaust nozzle where the exhaust steam is used to provide draft for the fire. In superheated locomotives, also contains the superheater header and (optionally) a front-end throttle. A smokebox door allows access for cleaning.
An electric locomotive with a central cab and sloping "noses" on each end.
A person in a dining car with a role similar to that of a Maitre d’Hotel.
Pulling against train brakes at the lower end of a locomotive's power output, e.g. notches 1 through 4 of a conventional throttle, thus keeping coupler slack stretched and permitting smoother train handling. This is considered most effective on undulating track profiles or when dynamic braking is not available.
Stub (North America)
A relatively short section of track that ends at a bumper or wheelstop, most often found in a terminal. Not to be confused with a spur, which may be miles (kilometers) in length.
A railroad that runs underground, generally in a large city. Subways are also considered "heavy rail" because they operate on their own dedicated track. Not to be confused with the interurban definition of subway, which is normally a light-rail passenger service running mostly underground.
A mechanical device that boosts the pressure of engine intake air to above atmospheric level, causing an increase in power. Not to be confused with the blower used to scavenge the cylinders of a naturally aspirated two-stroke Diesel engine.
Synonymous with cant : the banking of railroad track on curves. Specifically, the practice on high speed lines (where the cant needs to be higher) of gently introducing the elevation of the outer rail before the bend starts, in order to avoid sudden lurches.
to determine the position of constructed objects, including rail infrastructure, in relation to the earth's surface. This is accomplished by measuring angles and distances based on the principles of triangulation.
A locomotive that carries its own fuel and water instead of hauling a tender. The fuel is usually in a bunker behind the cab and the water in tanks on either side of, above, or below the boiler (respectively : side tank, saddle tank, well tank).
A specialized rail car attached to a steam locomotive to carry its fuel and water supplies, along with tools and flagging equipment.
An area, usually at least ten feet wide, between a pair of widely spaced tracks, wide enough to form a place of safety in which railway workers can stand while a train goes past. See also four-foot and six-foot.
A passenger coach that is disconnected from one train and attached to another before continuing on with its journey, thus avoiding the need for passengers themselves to switch trains.
The standard platform and track arrangement at a station. The train pulls alongside the platform, arriving from one end of the station, and may pass out the other end of the station by continuing along the same track.
Combining two or more different railways onto a common length of track. This is often done to eliminate redundant trackage and/or improve service.
A small explosive device strapped to the top of the rail to alert an approaching train of danger ahead. A torpedo creates a loud noise upon contact with a locomotive wheel, signaling the engineer to reduce speed to 20 mph or less; the train cannot resume its original speed until it has traveled at least a mile beyond where it encountered the device. Traditionally used in pairs to ensure that the sound registered with train crews, torpedoes today are essentially obsolete as modern locomotive cabs' soundproof construction renders the devices useless. (UK:Detonator)
The legal right of one railroad company to use the tracks of another, as agreed to by the companies concerned or their predecessors; may also be ordered by government regulators, for example, as a condition of a merger. Running powers (UK).
An electrical circuit that detects the presence or absence of locomotives and/or cars in a section of track, the section referred to as a block. Track circuits provide real-time inputs to signaling logic.
See Wayobjects under "W" below.
A form used by railroad employees that shows the locations of slow orders, maintenance of way work locations, and other conditions affecting the track and movement of trains.
The gradual application of superelevation and tighter curve radius, calculated with reference to the anticipated line speed and the final curve radius, on the approach to a bend. Also known as the transition spiral and spiral easement.
Trams that are designed to run both on the tracks of a city-based rail system and on the existing railway networks. Tram-trains dual-voltage capability makes it possible to operate at lower speeds on city streets and at over Template:Convert60 on main line tracks allowing travel in an extended geographical area without changing the method of transport.
A train whose cars all carry the same commodity, such as grain or oil.
Up (UK, etc.)
A direction (usually towards London, other capital city, or the headquarters of the railway concerned) or side (on left-running railways, the left side when facing in the up direction). The opposite of down. The up direction is usually associated with even-numbered trains and signals.
A continuous train brake which is fail-safe in operation; the brake is powered by a vacuum from the locomotive but the application is actually by atmospheric pressure when the vacuum is released. Now largely superseded by the air brake.
The linkage between a steam locomotive's pistons, steam valves, and driving rods, transmitting the steam's power to the drive wheels.
The rolling component typically pressed onto an axle and mounted on a rail car or locomotive truck or bogie. Wheels are cast or forged (wrought) and are heat treated to have a specific hardness. New wheels are trued to a specific profile before being pressed onto an axle. All wheel profiles need to be periodically monitored to insure proper wheel to rail interface. Improperly trued wheels increase rolling resistance, reduce energy efficiency and may create unsafe operation. A railroad wheel typically consists of two main parts : the wheel itself, and the tire around the outside. A rail tire is itself steel, and is typically heated and pressed onto the wheel, where it remains firmly as it shrinks and cools.
The process of a wheel climbing up and often off the inside or gauge side of the rail. It is a major source of derailments. Wheel climb is more likely to occur in curves with wheels whose flanges are worn or have improper angles. See Rail adhesion.
The inner section of a wheel that rides between the two rails. The angle between the wheel tread and flange is often specific to the rail to prevent wheel climb and possible derailments. See Rail adhesion. The wheel flange is part of the wheel tire.
The loss of traction due to a slippery rail or wheel. Wheel slip was common with steam engines as they started to move due to the excessive torque often generated at low speed. Steam engines carried sand dispensing gear to increase traction at the start of motion.
An historical railway occupation; people employed to tap train wheels with hammers and listen to the sound made to determine the integrity of the wheel; cracked wheels, like cracked bells, do not sound the same as their intact counterparts. The job was associated with the steam age, but they still operate in some eastern European countries. Modern planned maintenance procedures have mostly obviated the need for the wheel-tapper.
Train whistles are used as a safety warning and also by the engineer to communicate to other railroad workers. See train whistle for a description of the whistle code used to communicate. Also a nickname for an air horn on a diesel locomotive. Steam engine whistles were historically known as chimes in the US during the 19th century.
A system of describing steam locomotive wheel arrangements, e.g. 4-6-4, 2-10-2. The first number indicates the number of "pilot" wheels that help lead the engine into turns. The second is the number of coupled wheels ("drivers"). Third are the trailing idler wheels, usually to provide support to larger fireboxes. Articulated locomotives are similarly described. For example, a Union Pacific "Big Boy" would be described as a 4-8-8-4, wherein the pilot has four wheels, followed by two sets of drivers, 8 wheels per set, and a 4 wheel trailing bogie under the firebox. The numbers include the wheels on both sides of the engine, so a 2-8-2 engine would have one idler, four drivers, and a final idler on each side of the engine.
A largely superseded Level or Grade Crossing Warning Signal consisting of a swinging disc facing road traffic with a red light in the centre. The disc normally hangs straight down, but an approaching train will set it swinging from side to side, the red light will illuminate or flash, and a bell will ring.
Also "foaming" or "priming"; the condition of a steam locomotive drawing water through its throttle valve, cylinders, and smokestack, often causing damage to the cylinders or running gear.
A failure in a signalling system that leaves the system in a dangerous condition.
Satellite image of a wye where two approaches to the interchange have been abandoned
Canadian National Railways: Linguistic Services. Freight Car Inspection & Maintenance: English-French Vocabulary = Surveillance et entretien des wagons: vocabulaire anglais-français. Montréal: Canadian National Railways, 1973. Without ISBN or SBN