Jargon and Technical Terms - I

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For technical terms starting from M and until Z, and for terms in Indian languages, please refer to this page.

Glossary of Technical Terms in English: A – L

Adequate distance
In railway operational contexts refers to sufficient distance to ensure safety, such as a safe braking distance for the expected speed of a train.
The term used to refer to the physical route taken by the permanent way (tracks).
All-right signal
The flag or lamp signal exchanged by crew on one train with crew on another train moving in the opposite direction, indicating that the track ahead is clear for the other train.
All stoppage
'All stoppage' refers to a suburban train (in the Kolkata area) which stops at all stations. Compare 'galloping local'.
Approach lighting
Refers to signals that are automatically controlled by the approach of a train.
The apron refers to a surface of concrete or other material in which tracks are laid; e.g., where stock is to be maintained or washed, goods to be loaded or unloaded, etc. A washable apron is one with provision for water drainage, where rolling stock can be washed.
The automatic notching down that happens in many locos (e.g., the WAP-4), if the driver notches up too aggressively resulting in the current and voltage rising excessively. See below for notch and regression.
Back light
Refers to lamps at the rear of a signal provided so that cabin crew can visually verify the aspect of a signal at night even if the signal faces away from them.
Balancing speed
The constant cruising speed that can be maintained by the loco for a given load on a given gradient (if none is specified, for a level route). This is usually specified for the highest speed / lowest power setting of the engine (whether electric or diesel).
A locomotive that is used to assist the main loco of a train on certain sections, e.g., on steep ghat (hill) sections, where more tractive effort may be required. Also known as a helper. See the section on bankers
Beat section
is the same as a gang beat. A beat station is a block station at either end of a beat section.
Berth, tier
IR terminology for sleeping accommodations in a coach. A berth is the term used for a sleeping bunk in a compartment. The number of such berths that are provided one above the other determines the number of tiers: a 2-tier coach has one upper bunk and one lower one (which forms the seats for daytime travel), a 3-tier one has two bunks above the lowest. 3-tier coaches actually usually have a combination of 3-tier arrangements crosswise and 2-tier arrangements lengthwise along one side of the coach.
The layer of material provided just below the ballast layer in a track formation. (Note: IR does not use sub-ballast layers.)
In addition to its meaning as used in block section or block working has another meaning which is a stoppage or restriction placed on traffic on a section of track. See the section on operations for details of different kinds of blocks such as line block, traffic block, power block, local block, etc.
Block back
To notify the signal staff controlling the next block in the rear on a double line (or the next block on either side for a single line) that the block section is obstructed or expected to be obstructed. Similarly, to block forward is to notify signal staff of a block section ahead of an obstructed block section.
Block rake
A freight rake that consists entirely of one shipment (e.g., all the wagons in it may carry iron ore, or all of them may carry containers) for one destination. The rake itself may be earmarked for a particular private shipper or other firm or may be leased by one and might be reused for several journeys. IR prefers block rakes because they do not entail the overheads of marshalling the wagons, delays because of loading or unloading en route, etc.
Block station, block hut, block post, halt station, flag station
See the section on signalling. for more on these and related terms
Block system
For information on block system terminology such as absolute block, automatic block, block instrument, permissive block, moving block, etc. please see the section on signalling.
Blotter Test or Blotter Spot Test
This is a quick check that can be carried out to check the condition of locomotive crankcase oil without the use of sophisticated equipment or laboratory facilities. A drop of crankcase oil is deposited on a sheet of absorbent paper (hence 'blotter spot'). The appearance of the drop as it spreads into the paper provides clues to the condition of the oil: contamination is revealed by how dark the spot is; dispersion characteristics of the oil can be judged by how far it spreads and how big the central sooty area is; fuel oil makes the core of the dispersing spot irregular, and water in the oil adds a definite boundary and makes the halo area smaller.
A wheel-set (US: truck) in technical parlance, but in colloquial Indian English the term is often used to refer to a passenger compartment in a coach, or to the coach itself if it is subdivided into compartments.
Bogie stock
Refers to a wagon (also known as bogie wagon) or coach that is mounted on (usually) two bogies (usually 4-wheeled) in such a manner that the frames are not rigidly attached to the bogies, allowing the bogies or trucks to swivel around, which allows them to follow curves better. Contrast with unit wagon
Booking A Driver
To assign him to a particular link train.
Booked speed
The maximum speed at which the train needs to travel in order to maintain the time-table schedule, if running on time. See the items related to working timetable and scheduling in the section on operations.
The turbocharger of a diesel locomotive.
Bradshaw ,The
The colloquial term for Bradshaw's Monthly Railway Guide, a periodical publication containing railway schedules for Great Britain, first produced in 1839 by George Bradshaw. The Indian Bradshaw or Newman's Indian Bradshaw, first published in 1866 and still being produced, is modelled on it and is a publication containing the schedules of all important trains in India.
Brake halt
A mandatory halt for a train on a prolonged incline section in a ghat area, especially if adequate catch sidings do not exist. A brake halt may be at a normal station, or it may be a halt without a station. The driver is required to bring the train to a dead halt, and sign a register kept by a watchman at the halt (if there is no station), and then proceed. Examples of brake halts are Khandala, Monkey Hill, and Nagnath.
Cant or super-elevation
The banking or tilt provided to the tracks on curves to allow easier passage of trains. It reduces the frictional force needed to hold the train on the tracks (instead of having them fly off the tracks through centrifugal forces!). As trains of different speeds use a line, and as trains may come to a halt on the curve, the actual cant provided is a compromise that works well for most trains but does not pose a safety problem for trains that might halt at the curve.
Cash Local
The daily train running on WR's Mumbai suburban lines for collecting and transporting cash from every station, and similar other trains in other big metropolitan areas.
Catch siding
A siding provided with an upward incline coming off a downward track, to stop a runaway vehicle. Normally the train is required to stop at a signal, and the facing points are set for the catch siding. After the train has come to a halt, the points are set for the main line and the train can proceed. Should a runaway train reach the points at speed, it is diverted on to the catch siding which in addition to being inclined upwards also has loose sand on the trackbed to absorb the kinetic energy of the train and bring it to a halt. Catch sidings are often also provided at the outermost stop signal on the approach to a station or yard, to prevent runaway vehicles from entering the station or yard limits. See also slip siding.
The structure of cables above the track which carries the electric supply for electric locomotives that use overhead electricity collection. The actual cable that carries the current is contact wire. Loosely, the term 'catenary' may also be used for the contact wire itself. Usually the contact wire is suspended from another cable, called the messenger, by means of short vertical supporting cables called hangers. A secondary messenger may also be used in some cases.
Caution order
A temporary speed restriction in place for a particular section of track, because of track damage, construction work, etc. Caution orders are given to drivers at the station to the rear of the section where the caution order is in effect.
The part of the top of the track formation from the toe of the ballast to the edge of the formation; less commonly, the space between an outer rail and the edge of the track-bed or permanent way structure. A cess also refers to a charge or surcharge of some sort, e.g., a special surcharge on tickets to pay for rising petroleum costs.
The chain (sometimes alarm chain) in a train is the emergency brake chain provided in passenger coaches. Chain pulling is the act of pulling it to stop a train, whether for an emergency or (often) illegally for someone to get on or off the train.
Chair car
Passenger coach type that has no berths or other sleeping accommodation. It has only individual seats (no bench-style seating).
Chargeable distance
IR's fares are generally computed on the basis of the official distance between the end points for a particular route. The fares for some routes, however, are different than the fare expected based on looking up the fares for the actual route-km in a fare table. These are lines with very sparse traffic, tourist lines or lines with other special conditions. In such cases, there is a chargeable distance associated with the route, which is the distance to be used when looking up fares in a fare table, regardless of the actual route length.
For instance, the Neral-Matheran NG route is only about 21km long, however the ticket fare for the journey is based on a chargeable distance of 126km (and in fact, the distance markers along the way show the chargeable distances, not the physical distance!). Other routes for which chargeable distances differ from the actual distance are Kalka-Shimla, Pathankot - Joginder Nagar, Purna-Khandwa (MG, in the 1980s), etc.
Konkan Railway also charges fares based on a chargeable distance being 40% higher than the actual distance, a measure intended to recover some of the construction costs for the lines. In some rare cases the chargeable distance is lower than the route length -- for instance, at one time trains on the Grand Chord and the Main Line between Howrah and Mughalsarai had tickets with the same chargeable distance (660km), even though the Main Line route came to 757km.
Check rails
See guard rails.
Circular journey
A journey starting and ending at the same station, but with different routes out and back.
City booking office
A booking office run by IR or a private agency and situated in a city but not at the railway station. Also called an agency sometimes
Cloak room
Term for the left-luggage or locker facility at a station.
Closed circuit rake
A freight rake that is dedicated for one kind of freight and which keeps travelling around a certain fixed closed loop route. E.g., cement plants to freight depots and back.
Cluster Station
A station that is not on a given route, but for which tickets and reservations may be issued on trains travelling on the route. Usually a 'cluster' of stations is defined near the originating station of a route (the 'source cluster') and also near the terminating station (the 'destination cluster') for purposes of ticketing.
Coaching stock
Includes any rail coaches or carriages other than freight cars (wagons, q.v.). Contrast with goods stock.
Codal life
The normal working life prescribed in the rules for computing asset life and depreciation in IR's Finance Code. Applicable to coaches, wagons, etc
Combined train report / CTR
A report compiled by the guard and signed by both the guard and the driver of a train, that records the salient points of the train's journey — its times at various stations en route, any problems encountered, etc.
Commercial speed
The average speed of the train for a section of the route — i.e., distance between endpoints divided by the time taken, including the time taken for technical halts and such. See the items related to working timetable and scheduling in the section on operations.
General term for points, crossings, and other devices that allow a section of track to connect to or cross another track.
(Container Rajdhani) is the name given to some of the fast freight trains between Mumbai and Delhi.
Continous brakes
The system where vacuum brake or air-brake pipes run through the entire rake connecting with the brakes on each coach or wagon, so that a failure anywhere or a parting of the rake causes the brakes to be applied on all vehicles.
A turnout that curves in a direction opposite to the direction in which the main track curves.
Also called section controller. One who implements the dispatchers' plans and controls the movement of trains and locos in a section. See Scheduling.
Coolie / Kuli
A porter. The term does not quite have the connotation of being derogatory that it does in US or UK English, although some now consider it old-fashioned.
Construction number
Also known as the maker's number is the serial number assigned to a locomotive by the builder. Contrast operating number.
Corridor system
A method of train working where many trains can be scheduled to follow in quick succession. See section on train working for more on such non-block systems, including pilot guard, line clear, etc.
In addition to its obvious meaning as the coupling mechanism between coaches, wagons, or locos, also has as an informal meaning a lashed-up set of two banker locos (usually applied to a pair of lashed-up WCG-2 bankers). Similarly, a tripler is a lashed-up set of three bankers.
The old GIPR EF/1 (WCG-1) rod-driven C+C locomotives were termed crocodiles probably because of their appearance, with a fat middle portion and unusual overall length. The term appears to be of Swiss origin and was adopted by the British. Locally, in the Bombay area, however, they were known as khekda or crabs. More information.
An intersection of two tracks (without necessarily allowing for movement of trains from one track to the other). Sometimes used loosely for crossover.
An arrangement of rails that allows movement of trains from one track to another. Sometimes the word crossing is also loosely used for this.
Crush load
Refers to a passenger coach or EMU carrying more passengers than the standing load it is designed to carry under normal circumstances. The Mumbai suburban system is notable for the official use of the terms dense crush load, super-dense crush load, and hyper-dense crush load to describe various degrees of the incredibly crowded conditions found on the trains at rush hour. A 9-car EMU rake designed for 1800 passengers (standing load) in practice carries up to 7000 (!!) passengers at rush hour; this includes not only people in the car but hanging out of the doors, from the windows and the gutter along the roof, on the couplers, and on the roof of the car!
Curves and curvature
Curves are, of course, any sections of track that are not straight. A curve's degree of curvature is specified in a couple of different ways. Often, an angular measurement is provided (e.g., 3.5° = 3.5 degrees, sometimes written as 3.5d). This is the angle subtended by a 100' chord at the centre of the curve (even in the metric world, although 20m chords or other lengths are sometimes used). (Do not confuse this with the total curvature of a section of track which is also measured in degrees of angular deviation.) Sometimes, especially in European countries, the radius of curvature is directly specified to determine the curvature.
Dead man's pedal
A handle or knob that is spring-operated or otherwise designed so that that the driver has to engage it continuously in order for the locomotive or EMU to run; if he releases the pedal, the loco stops immediately.
Stands for the Diesel Loco Works, Varanasi, from the acronym of the Hindi name, 'Diesel Rel Karkhana'.
A train, wagon, or other facility used solely for IR's own purposes such as construction or repairs, and not for commercial or customer service. E.g., a departmental train may be one that carries ballast, equipment, repair tools, etc. Also see traffic and material train.
Derailing block
A wedge-shaped block attached to a rail which can be pivoted above the rail, in which position it is designed to derail any vehicle that passes over that track. The purpose is similar to that of derailing points explained below. Also seen are Hayes' derails which similarly serve to derail a vehicle.
Derailing points
Sometimes called a derailing switch : see trap points.
Common IR misspelling of 'destressing' (as in track destressing).
Term for delaying a train at a station in order to allow other trains to pass or for other reasons. The working timetable usually indicates allowable normal detention times for various trains at each station. A detention for the purpose of allowing scheduled trains to connect with other services is an authorized detention.
Detention charges
Hourly fees to be paid for the duration that a specially hired tourist coach is parked at a station.
Diamond crossing
Refers to the crossing of two tracks at an angle (the rails form a diamond-shaped figure in the middle).
The official who determines the overall schedules and precedence of various trains. See Scheduling.
Distant green
A distant signal which is clear (showing the Proceed aspect).
Indian Railways pay 'dividends' to the government in most years. The terminology dates from British India when railway companies were set up with capital and loans from the government together with guaranteed return rates. Dividends are technically considered to be interest payments on the capital account (all of which -- today -- is from the government) which is considered to be a 'loan in perpetuity' from the government to IR.
The crewperson who operates the locomotive; the one who would be called an 'engineer' in US parlance.
A common mispronunciation of the word 'dome' on IR; e.g., 'steam doom', 'doom light'. Sometimes even written this way.
Drivers' Lobby
An office where Drivers and Guards sign in for duty and sign out after handing over a train to a fresh crew.
Dual-gauge track
A mixed-gauge track with three rails, of which the middle one and one of the outer ones form a track of the narrower gauge and the outer two form a track of the broader gauge. Sometimes also applied to mixed-gauge track where each gauge has its own pair of rails, but one track is completel embedded within another with both sharing a common centreline. Compare gauntleted track.
Dwell time
Also called station dwell time is the amount of time an urban or suburban commuter train stops at one of its stations. On the Mumbai suburban system, dwell times are usually 30 seconds for bigger stations and 20 seconds for all others.
Edmondson ticket
Tickets issued on pre-printed card stock with a machine-punched serial number. Named for Thomas Edmondson (1792-1851) of Lancaster, UK, who invented them as a way to issue tickets more efficiently and reduce fraud at the Newton and Carlisle Railway, UK, in the 1830s. These were almost universally used on British railways from the second half of the 19th century and also in India, until fairly recently. Typically 57.5mm x 30mm in size, on cardboard about 0.8mm thick.
Emergency crossover
A crossover provided for diverting runaway vehicles to a catch siding or other track away from the main running line. A common form of this is to have a catch siding (dead end at both sides) with a scissors crossover to the main running line, and points normally set to divert vehicles on the running line to the catch siding.
Engine local
(Informal) A term used in the Chennai area for some loco-hauled local or suburban services (in contrast to unit, q.v. which referred to EMUs).
Escape track, escape siding
At a terminus station, tracks leading to the platforms are often dead-end tracks. If a loco pulls a train in, the loco cannot be used during the time that the train is at the platform, if there is no way for the loco to get out. To allow the loco to return to the shed or be used somewhere else, an escape track is provided to which the loco can be switched after uncoupling from the train and from there get out of the station.
Express train
See the section on operations for more on this and related terms.
Equipment that is designed to maintain safety even when a failure occurs in any component. The most common example is a signal that is designed to switch to a Stop aspect if there is any failure in the circuitry.
Used to introduce a train into the online reservation system, making it available on the system for ticket sales and accommodation allotment.
Fly shunting
The operation generally at hump yards, of loose shunting two (or more) wagons at once, but manipulating the points adroitly between the successive wagons to divert them to different lines.
To ride in the cab of a locomotive, from the old term footplate from steam days, referring to the horizontal surface projecting from the locomotive frame, on which the loco cab was constructed. Although diesels and electrics do not have a footplate like that, the terminology persists.
Also 'track formation', this is the term for the entire track structure below the rails and ballast layer -- including the blanket, subgrade, and sub-soil layers. Also sometimes used as a term for a rake, as in a 'train formation'.
Refers to anything attached directly to the frame of the bogie itself, as opposed to being attached to one of the axles of the bogie. eg: Frame mounted motors, brake equipment, etc.
The intersection between two rails at a crossing, with clearances or channels for the wheel flanges to pass through when going in any direction from one track to the other.
A flare in the shape of tube of combustible material with a metal handle at one end, which can be lit to provide indication of an emergency condition or as a distress signal. The flare is visible for about 2km, and continues burning even in rainy conditions. Level crossing gatekeepers, guards, and other staff have these with them for emergency use.
Galloping local
A suburban train that skips intermediate stops (Kolkata area). See the section on operations for more information on types of suburban train services. In contrast to 'All stoppage' (cf.).
A worker involved with inspection and maintenance of the permanent way, so called because gangmen work in groups of gangs. A gang beat is the regular section of track that it is the duty of a gang to work on. (Also known as beat section. The gangmate or gang mateis the head gangman of a gang.
The railway staff person in charge of a level crossing gate.
The width of railway track measured as the distance between the rails. Also used for the instrument used by gangment for verifying the gauge.
Gauntleted track
Refers to a situation where one track's rails are interlaced with those of another track. (E.g., four rails where 1 and 3 form one track, and 2 and 4 form another.) The tracks may be of the same or different gauges. This is used to save space in the loading gauge or clearances required (e.g., tunnels, bridges). Of course the section has to be treated as a single line for signalling purposes. Also known as interlaced track. Compare dual-gauge track.
Ghat section
A section of the railway route that goes through hilly areas with significant grades. A ghat is a term in some Indian languages (e.g., Marathi) for a hill or mountain (for instance, in the names Western Ghats, Bhore Ghat, Thull Ghat, etc.). IR terminology also refers to semi-ghat sections -- definition??
Golden quadrilateral
The routes connecting the four metropolises of New Delhi, Mumbai, Chennai, and Kolkata. These are the routes that generate the most revenue for IR, both in freight and passenger operations. Although in route length they sum up to about 16% of IR's total network, they carry 65% of the freight and 55% of all the passenger traffic.
Goods avoiding line
(GAL) is a diverted route that goods trains take to avoid going through busy stations or areas with heavy passenger traffic.
Goods stock
Includes all freight wagons. Contrast with coaching stock.
Ground exhauster
An arrangement at a marshalling yard whereby a pump provides a vacuum that can be tapped into from a pipe near the tracks. This pipe is fixed to the (vacuum) brake system of a freight rake to simulate the vacuum created by a locomotive's exhauster, allowing testing the brake system before sending the rake out.
Guarantee system, guaranteed railways
Refer to the section on history.
Guard rails
Sections of rail provided parallel to the rails of the track (on the inside) at road crossings, bridges, viaducts, etc., to guide the flanges of the train wheels, and, in case an axle is derailed, to prevent the derailed wheels from moving away from the track in order to limit the damage to the bridge or other structure, or to prevent derailments in places where extrication might be unusually difficult. They bear on the back of the wheel flange in situations where the other wheel on the same axle might have a tendency to leave the track. Apart from bridges and the like, these are also found opposite the 'V' of points and on very tight curves. They are also known as check rails. In IR documents, often the term 'check rail' is used for those provided at sharp curves, points, and level crossings (where the gap provided is smaller), and the term 'guard rail' is more commonly used for those used on bridges and viaducts (where the gap is larger). See the permanent way FAQ for more details.
Gumti, Goomti, Gumty, Goomty
A small cabin, as for the guard at a level-crossing, or even any small structure covering a lever frame or other fixed equipment. From Hindi.
Hammer blow
The phenomenon in steam operation where the inherent dynamic imbalance of the driver wheels and their linkage rods causes the rails to be subjected to intense and regular pounding, in some cases causing severe damage to the rails (also known as dynamic augment).
Hand shunting
A form of loose shunting of an individual wagon where a railway staff person mans the wagon while it is being shunted (uncoupled) and applies the hand brake at appropriate times. Done at low speeds and on flat terrain. Hand shunting also refers to instances where a single wagon is moved by human labour — several workers pushing on the wagon! (On occasion elephants have been used for shunting too!)
An interlocking spanner used to operate a control in an EMU or locomotive. See private handle.
Also knows to as lead. Refers to the distance a passenger or unit (1 tonne) of goods is transported. This arises usually in the term average haul or average lead, the average distance a passenger or tonne of goods is transported.
The amount of time provided between consecutive trains running on the same tracks. Safety concerns (involving signalling, block length, braking distances, etc.) put a lower bound on the headway, which in turns puts a limit on how busy a section can be.
Home double
Term used for signals in the modified lower quadrant system showing clear for both the warner and the home signal on the same mast.
Home shed
A loco is typically homed at a particular shed; i.e., it is maintained there, sets out on a trip from there and returns to that shed when done, and essentially belongs to that shed for most purposes. Similarly, a rake is usually based at a particular station's yard, it's home yard, which is in charge of its maintenance and for preparing it before the rake is assigned to a train heading out from that station.
Hotel power
The electricity supply to power lights, fans, and other fittings in passenger coaches. This may be provided by batteries, generators in the coaches, or from the loco, or from a station where the train is stopped, or some combination thereof.
Any structure or object that is situated too close to a track so as to impinge upon the loading gauge of the track or be so close as to present an unsafe condition for trains moving on the track.
A signalling or communication circuit (such as a block instrument circuit) is said to be immunized if provision has been made to protect it from electromagnetic and inductive interference from OHE equipment.
A generic term for minor signals other than the main block signals: shunting indicators, points indicators, trap indicators, etc.
Integral coach
See the section on rolling stock.
Irregular travel
Term encountered in official documents and refers to ticketless travel or travel by passengers on improper tickets, without reservations, etc.
Island Platform
A platform that has tracks on both sides, so that it can only be reached by an bridge over the tracks or an underground passage below the tracks.
Refers to setting points and working the interlocking system for a line in such a way that it is free from the danger of obstructions from other lines connected to it.
A grade of worker in IR's hierarchy; e.g., the shunting jamadar whose job it is to couple or uncouple wagons and keep track of the marshalling of wagons in non-automated marshalling yards.
Jamalpur jacks
High-capacity electrically operated synchronized lifting jacks first manufactured by Jamalpur workshops (1962).
Joggled fishplate
A fishplate with a 'bump' or bent portion that is used to join sections of rail temporarily, in emergency situations (rail fracture) or when carrying out repairs or after thermit welding.
A common term (Pune division, etc.) for the WDM-2 model with a low, full-width windscreen. Also known as a low bonnet. For jumbo rake, super-jumbo rake, see the section on freight.
A meeting point of two or more routes. Sometimes the term is also used for a station where there is a single route but the gauge changes (e.g. Kalka Jn. where the BG line terminates and the NG line to Simla originates).
A spanner (wrench) such as the one used by a keyman to tighten fishplate bolts.
A member of the track gang who is in charge of the keys and other tools for tightening fishplate bolts and carrying out other such maintenance. The keyman is also usually the one in charge of inspecting, usually visually, the entire length of track on the gang beat on the daily patrol, unless there is a separate patrolman. The other members of the gang work on fixing the defects found in the keyman's inspection.
Also refered to as chargeman. They are technicians at different levels of IR's hierarchy.
King lever
A signalbox lever which when operated cuts out the box entirely and allows its signals and points to be worked remotely from the adjacent signalbox. Signalboxes were often coupled in pairs (e.g., Madras Beach and Madras Egmore in the 1940s) with king levers like this.
King points
Points in a marshalling yard just at the shunting neck, where the approach tracks split into the numerous tracks used for marshalling and classification (near the hump).
Kopcke siding
A term occasionally encountered for a catch siding — it refers to a particular design that was in use in some places.
A period of waiting for loco crew to pick up the link train to return to their home shed.
See haul.
Level crossing
A 'railroad crossing' in US parlance.
The period during which a rake is kept unused at a station or yard in between its use for scheduled trains.
Light engine
A loco travelling by itself (no load) on the main line using regular signals.
Line Box
A box with equipment (flashlights, flares, spare bulbs, track detonators, etc.) and documents carried on a locomotive. See the section on operations.
Line capacity
Sometimes called sectional capacity. Refers to the maximum number of trains that can be routed through a section in a day (24 hours). Contrast with throughput below.
Line Clear
Permission given by a block station to the block station in rear for a train to depart from the latter and approach the former.
Line gear
Refers to the gearing of a shunting locomotive set when working at higher speed, for light to medium haul duties (e.g., running light, or hauling a passenger as happens on occasion).
A schedule of assignments to various trains, going out of his home station and back to it, in the duty chart of a driver. Also known as a diagram. The overall crew allotment for different trains is detailed in a crew link. See also rake link. For more details see the section on operations.
The rake being pulled by the loco. A locomotive is on load when it is attached to its rake of coaches or wagons. The term load also refers to the number of passengers carried in a coach
Load table
Usually found in working timetables, indicates maximum allowable loads (number of coaches or wagons of different kinds) for different combinations of motive power (different locomotives singly and in combinations).
Local, fast, semi-fast, double-fast
See the section on operations for more on this and related terms.
Locking bar
A device used at facing points, to lock point blades in place so that the points cannot be changed as a train moves over them; it is activated by the flanges of the train's wheels pressing down a bar that extends about 5-10m along the rails from the points. Usually the mode of operation is mechanical, but electrically operated arrangements which block electric points operation have also been used.
Locking table, selection table, route selection, route holding
The section on interlocking gives more information on this.
Also known as loop siding. Refers to any siding that connects to a running line at both ends.
Loose shunting
Refers to the shunting of wagons or coaches not attached to the shunting locomotive.
Luting sand
Sand used to fill in gaps when fitting a mould to a component such as a rail before welding or pouring molten metal, as in thermit welding.

More terms (M - Z) in the next page. Also find terms in other Indian languages.