NationMaster - Encyclopedia: UIC classification

The UIC classification is a comprehensive system for describing the wheel arrangement of locomotives. It is the system generally used in much of the world, but it was not widely used in the United Kingdom, other than partially on the Southern Railway under chief engineer Oliver Bulleid, or in the United States; a simplified form is used in both countries for modern locomotives. It is a more versatile system than Whyte notation, making fewer assumptions about locomotive layout. In the latter notation, some locomotives are impossible to classify; UIC classification handles them easily. The UIC classification is also much more suited to diesel and electric locomotives. The International Union of Railways (French: Union Internationale des Chemins de Fer; abbreviation: UIC) is the name for the international rail transport industry body. ... Locomotive wheel arrangement is how the wheels of the locomotive are arranged by type, position, and connections. ... A locomotive (from lat. ... The Southern Railway in the United Kingdom was geographically the smallest of the four railway systems created in the Grouping ordered by the Railways Act 1921. ... Oliver Vaughan Snell Bulleid (19 September 1882 - 25 April 1970) was a British railway and mechanical engineer best known as the Chief Mechanical Engineer (CME) of the Southern Railway between 1937 and the 1948 nationalisation, developing many well-known locomotives. ... A selection of early 20th century locomotive types according to their Whyte notation and their comparative size The Whyte notation for classifying steam locomotives by wheel arrangement was devised by Frederick Methvan Whyte and came into use in the early 20th century. ... Great Western Railway No. ... East German E 18 electric locomotives of the Deutsche Reichsbahn An electric locomotive is a locomotive powered by electric motors which draws current from an overhead wire, a third rail, or an on-board storage device such as a battery or a flywheel energy storage system. ...

Whereas the Whyte notation counts wheels, the UIC notation counts axles (actually wheelsets, since axles are not always present). Upper-case letters of the alphabet, starting at A for a single axle, are used to denote driving axles, and non-driving axles are denoted by numbers, starting with 1 for a single axle. For example a Pacific-class steam locomotive, denoted 4-6-2 in Whyte notation, has a UIC designation of 2-C-1. On some locomotives non-driving axles are mounted on steerable bogies; this is sometimes indicated via the use of apostrophes in UIC notation, as 2-C1'. A bogie is a wheeled wagon or trolley. ...

Articulated locomotives are indicated using brackets or a "+" (plus) sign. Mallet locomotives can be indicated by bracketing the front power unit — for example, the Union Pacific Big Boy — denoted 4-8-8-4 in Whyte notation, is designated (2-D)D-2 or (more commonly) 2-D+D-2 in UIC notation. Garratt-type locomotives are indicated by bracketing or placing plus signs between all individual units. Mechanically-separated permanently-coupled units are indicated using only a "+" (plus) sign. An articulated locomotive is a steam locomotive with one or more engine units which can move relative to the main frame. ... A typical European Mallet type, a narrow gauge 0-4-4-2 tank locomotive for a mountain railway (in this case, the RhB in Switzerland). ... Big Boy was the nickname universally applied to the Union Pacific Railroads twenty-five 4000 class 4-8-8-4 steam locomotives built between 1941 and 1944 by Alco. ... Garratt on the Welsh Higland Railway South African Garratt Diagram of a Garratt locomotive A Garratt is a type of steam locomotive that is articulated, normally in three parts. ...

On many electric and diesel-electric locomotives, axles are individually driven by electric motors — this is indicated by suffixing the driving wheel letter with a lower-case "o."

The designation can also have additional suffixes, denoting other features of the locomotive:

and sometimes followed by a number, indicating the number of cylinders in a steam locomotive. A tank locomotive (occasionally tank engine) is a steam locomotive that carries its own fuel and water with it, instead of pulling it behind it in a tender. ...

The most common wheel arrangements in modern locomotives are Bo-Bo or Co-Co, while steam locomotives and other older units can have many different wheel arrangements.

A1-1A

"A1-1A" means there are two bogies or wheel assemblies under the unit. Each truck has one powered and one idler (non-driven) axle, the latter intended to provide better load distribution and thereby reduce the wheel load on the track. All powered axles are individually driven (i.e., via traction motors).

A1A-A1A

"A1A-A1A" means there are two bogies or wheel assemblies under the unit. Each bogie has one powered axle, one idler axle, and one more powered axle, an arrangement intended to provide better load distribution and thereby reduce the wheel load on the track. All powered axles are individually driven (i.e., via traction motors).

B-B

"B-B" means there are two bogies or wheel assemblies under the unit. Each truck has two powered axles, connected by driving rods or gears. Three-quarters of all modern locomotives (as well as the power cars of self-propelled trains) are configured in either this or the "Bo-Bo" arrangement.

Bo-A1A

"Bo-A1A" means there are two trucks or wheel assemblies. The "Bo" truck is under one end of the unit, and has two powered axles, while the "A1A" truck is under the other end of the unit, and has one powered axle, one idler axle, and one more powered axle. All powered axles are individually driven (i.e., via traction motors).

Bo-Bo

"Bo-Bo" means there are two bogies or wheel assemblies under the unit. Each truck has two individually-driven powered axles (i.e., via traction motors). Three-quarters of all modern locomotives (as well as the power cars of self-propelled trains) are configured in either this or the "B-B" arrangement.

Bo+Bo

"Bo+Bo" means there are two bogies or wheel assemblies under the unit, either mounted to an articulated frame or set beneath two mechanically-separate permanently-coupled units. Each truck has two separately-driven, powered axles (i.e., via traction motors).

Bo-Bo-Bo

"Bo-Bo-Bo" means there are identical bogies or wheel assemblies under the unit. Each truck has two individually-driven powered axles (i.e., via traction motors).

Bo-Bo-Bo-Bo

"Bo-Bo-Bo-Bo" means there are identical bogies or wheel assemblies under the unit. Each truck has two individuallydriven powered axles (i.e., via traction motors).

Bo-Bo+Bo-Bo

"Bo-Bo+Bo-Bo" means there are identical bogies or wheel assemblies under the unit. The bogies are arranged in pairs and are either mounted to an articulated frame or set beneath two mechanically-separate permanently-coupled units. Each truck has two individually-driven powered axles (i.e., via traction motors).

C-C

"C-C" means there are two bogies or wheel assemblies under the unit. Each truck has three powered axles, connected by driving rods or gears.

Co-Co

"Co-Co" means there are two bogies or wheel assemblies under the unit. Each truck has three individually-driven, powered axles (i.e., via traction motors).

Co-Bo

"Co-Bo" means there are two bogies or wheel assemblies under the unit. Each truck has separately-driven, powered axles (i.e., via traction motors). The "Co" truck under one end of the unit has three powered axles, while the "Bo" truck under the other end has two powered axles.

Do-Do

"Do-Do" means there are two identical bogies, or wheel assemblies under the unit. Each truck has four separately-driven, powered axles (i.e., via traction motors).

1-B-B-1

"1-B-B-1" means there is one leading idler (non-driven) axle, two center-mounted bogies with two powered axles each connected by driving rods or gears, followed one trailing idler axle.

1-Bo+Do+Do+Bo+1

"1-Bo+Do+Do+Bo+1" means there is one leading idler (non-driven) axle, one bogey with two powered axles, and one bogey with four powered axles mounted to the leading end unit; a center unit that shares the four-axle bogey with the leading end unit, along with another four-axle bogey that is shared with the trailing end unit; and a trailing end unit with a wheel arrangement that mirrors that of the leading unit. This arrangement (or similar configurations) is typical of that found on permanently-coupled passenger trainsets.

1-C-1

"1-C-1" means there is one leading idler (non-driven) axle, one center-mounted bogie with three powered axles connected by driving rods or gears, followed one trailing idler axle.

1-Co-Co-1

"1-Co-Co-1" means there is one leading idler (non-driven) axle, two center-mounted bogies with three separately-driven, powered axles (i.e., via traction motors), followed one trailing idler axle.

1-D

"1-D" means there is one leading idler (non-driven) axle followed by one bogie with four powered axles connected by driving rods or gears.

1-D-1

"1-D-1" means there is one leading idler (non-driven) axle, one center-mounted bogie with four powered axles connected by driving rods or gears, followed by one trailing idler axle.

1-Do-1

"1-Do-1" means there is one leading idler (non-driven) axle, one center-mounted bogie with four separately-driven, powered axles (i.e., via traction motors), followed by one trailing idler axle.

1-E-1

"1-E-1" means there is one leading idler (non-driven) axle, one center-mounted bogie with five powered axles connected by driving rods or gears, followed by one trailing idler axle.

2-B-B-2

"2-B-B-2" means there is one leading idler bogie with two non-driven axles, two center-mounted bogies with three powered axles each connected by driving rods or gears, followed by one trailing idler bogie with two non-driven axles.

2-B+B-2

"2-B+B-2" means there is one leading idler bogie with two non-driven axles, two center-mounted bogies with three powered axles each connected by driving rods or gears, followed by one trailing idler bogie with two non-driven axles. The bogies are arranged in pairs and are either mounted to an articulated frame or set beneath two mechanically-separate, permanently-coupled units. Each truck has two separately-driven, powered axles (i.e., via traction motors).

2-Bo-Bo-2

"2-Bo-Bo-2" means there is one leading idler bogie with two non-driven axles, two center-mounted bogies with three separately-driven, powered axles each (i.e., via traction motors), followed by one trailing idler bogie with two non-driven axles.

2-C

"2-C" means there is one leading idler bogie with two non-driven axles, followed by one bogie with three powered axles connected by driving rods or gears.

2-Co-1

"2-Co-1" means there is one leading idler bogie with two non-driven axles, once center-mounted bogie with three separately-driven, powered axles (i.e., via traction motors), followed by one trailing idler axle.

2-Co-2

"2-Co-2" means there is one leading idler bogie with two non-driven axles, one center-mounted bogie with three separately-driven, powered axles (i.e., via traction motors), followed by one trailing idler bogie with two non-driven axles.

2-D-1

"2-D-1" means there is one leading idler bogie with two non-driven axles, one center-mounted bogie with four powered axles connected by driving rods or gears, followed by one trailing idler axle.

2-D-1+1-D-2

"2-D-1+1-D-2" means there is one leading idler bogie with two non-driven axles, two center-mounted bogies with three powered axles each connected by driving rods or gears, followed by one trailing idler axle, mounted to an articulated frame or permanently-coupled to another mechanically-separate unit with an identical assembly mounted in the reverse (mirror) position. The axles on each powered bogie are connected by driving rods or gears.

2-Do-1

"2-Do-1" means there is one leading idler bogie with two non-driven axles, one center-mounted bogie with four separately-driven, powered axles (i.e., via traction motors), followed by one trailing idler axle.

2-Do-2

"2-Do-2" means there is one leading idler bogie with two non-driven axles, one center-mounted bogie with four separately-driven, powered axles (i.e., via traction motors), followed by one trailing idler bogie with two non-driven axles.

2-Do-Do-2

"2-Do-Do-2" means there is one leading idler bogie with two non-driven axles, two center-mounted bogies with four separately-driven, powered axles each (i.e., via traction motors), followed by one trailing idler bogie with two non-driven axles.

References

Contents

A1-1A

A1A-A1A

B-B

Bo-A1A

Bo-Bo

Bo+Bo

Bo-Bo-Bo

Bo-Bo-Bo-Bo

Bo-Bo+Bo-Bo

C-C

Co-Co

Co-Bo

Do-Do

1-B-B-1

1-Bo+Do+Do+Bo+1

1-C-1

1-Co-Co-1

1-D

1-D-1

1-Do-1

1-E-1

2-B-B-2

2-B+B-2

2-Bo-Bo-2

2-C

2-Co-1

2-Co-2

2-D-1

2-D-1+1-D-2

2-Do-1

2-Do-2

2-Do-Do-2

References

See also

Contents

A1-1A GA_googleFillSlot("encyclopedia_square");

A1A-A1A

B-B

Bo-A1A

Bo-Bo

Bo+Bo

Bo-Bo-Bo

Bo-Bo-Bo-Bo

Bo-Bo+Bo-Bo

C-C

Co-Co

Co-Bo

Do-Do

1-B-B-1

1-Bo+Do+Do+Bo+1

1-C-1

1-Co-Co-1

1-D

1-D-1

1-Do-1

1-E-1

2-B-B-2

2-B+B-2

2-Bo-Bo-2

2-C

2-Co-1

2-Co-2

2-D-1

2-D-1+1-D-2

2-Do-1

2-Do-2

2-Do-Do-2

References

See also

A1-1A