African Union of Railways

The African Union of Railways is an organisation under the auspices of the new African Union dealing with railways. It is similar to the International Union of Railways (UIC).

Overview

Africa's railways are disjointed and disconnected. The AUR hopes to rectify things. In 2012, there seem to be a large number of railway projects about to get off the drawing board, some of which will connect railway systems in different countries. The more interconnectivity, the more the need for consistent standards.

Standards

Gauge

The AUR sees that conversion to a common gauge is too difficult and expensive due to the gauge muddle, but based on reports from the World Bank, does see the following gauges as preferred in the following regions:

Several railways such as Senegal, Guinea and Tanzania have talked about conversion to standard gauge, though it remains to be seen if talk develops into action. Guinea built one new branch as standard gauge even though metre gauge is needed to take the ore to the port. Nigeria has built one short branch with dual gauge sleepers, and a network aiming to serve the port of Warri is also standard gauge. An extension from Tanzania into Rwanda is proposed as standard gauge, though it starts at a station that is already a container transhipment dry port. Mining railways that carry very large tonnages (> 10,000 metric tonnes per year) are generally standard gauge.

However, conspicuous by their absence, is the possibility of dual gauge, variable gauge axles, bogie exchange, piggy back operation and even triple gauge.

Timeline

2014

Construction of standard gauge lines has started in

Break of gauge

Because the mainlines of different countries of different gauges rarely meet, except Kidatu, break of gauge is paradoxically not a problem at the moment.

Couplings

Couplings in use include:

The American AAR coupler is the most widely used of the modern types, and is usable with the heaviest trains of regularly 32,000 t (31,500 long tons; 35,300 short tons).

Whatever the advantages of the modern SA3 coupler, it is not as widely used as the AAR. It is not clear if the SA3 is suitable for the heaviest (30,000 ton) trains.

Match wagons can overcome incompatibilities at the price of extra deadweight. Similarly with coupling adapters.

The type of coupling is less important when trains travel in fixed block loads.

Modern wagons are usually built with drawgear designed for easy conversion to some kind of centre coupling such as the AAR or SA3.

Brakes

Westinghouse air brakes and vacuum brakes (or no continuous brakes at all) are usually fitted. Dual brakes or piped only can overcome incompatibilities. Vacuum brakes are considered to be obsolete. Electronically controlled pneumatic brakes (ECP) are starting to be fitted on faster, heavy-duty trains for higher performance, and the two ECP systems are compatible. Air brakes are to be preferred to vacuum brakes because of their greater power.

Electrification

Most railways is Africa are diesel-operated, but electrification where it exists it mostly conforms to the modern standard of 25 kV AC, with some obsolete systems using the older 3 kVDC. Trams in cities are usually low voltage such as 750 VDC. Dual and multi voltage locomotives and electric multiple units (EMUs) are proven technology. Africa has great hydro-electric potential to run electric trains with, though this would not happen overnight.

Loading gauge

Loading gauges vary considerably, and through trains would be forced to use the most restrictive loading gauge along its route. The structure gauge of tunnels and bridges needs to be about 1 m (3.28 ft) taller to allow for piggy back operation of trains of one gauge on the wagons of another gauge.

Axle loads

Axle loads vary considerable, depending on the strength of the track, especially the weight of the rails which are generally too light for modern traffic. A reasonable minimum rail weight is 40 kg/m (80.64 lb/yd), though 50 kg/m (100.80 lb/yd) or 60 kg/m (120.95 lb/yd) would be preferred for heavy duty use.

Train lengths and crossing loop lengths

Crossing loops should be as long as the longest likely train, considered globally. Some UIC standards are 750 and 1,500 m (820 and 1,640 yd).

Because of dangers imposed by wild animals such as lions, manual control of loops turnouts is not necessarily a good idea, and some degree of automation of these turnouts, and fencing, is desirable.[1]

Minimum radius

Limits speeds, although speeds are less important on minor branch lines. Minimum radius also affects heaviest trains, due to tendency to pull wagons off the rails and derail them.

Language

Confusion and even accidents can occur if more than one language (or accent) is used to operate a railway. A simplified language such as seaspeak would be useful to reduce such problems.

Namibia

As of 2007, Namibian railways built nearly 300 km (190 mi) of a line with Angola. Namibia has been using Tubular Modular Track. Tubular Modular Track maintains its track resilience even in harshest sandy desert conditions. Transnet Freight Rail in South Africa uses Tubular Modular Track in the main Ermelo yard on its 70 million tonnnes per annum heavy haul coal export line. The continuous support provided by Tubular Modular Track increases rails and turnout life by a factor of two and weld life by a factor of ten (compared to conventional and slabtrack offering discrete support for rails). The Passenger Rail Agency of South Africa (PRASA) uses Tubular Modular Track in stations to ensure fixed vertical alignment between platforms and trains.

Nigeria

These gauge plans may be upset by Nigeria's albeit glacial programme to convert its 1,067 mm (3 ft 6 in) gauge lines to 1,435 mm (4 ft 8 12 in) which would seed a standard gauge network in adjacent countries, especially those landlocked countries with no railways at all. Nigeria has installed some dual-gauge concrete sleepers just in case.

Libya

Libya started in 2007 building a completely new 1,435 mm (4 ft 8 12 in) railway system, albeit slowly. A link across the Sahara to Central Africa, probably Nigeria, would also spur the growth of 1,435 mm (4 ft 8 12 in) connections, which make use of continuous access to the Middle East, Europe, and even China in the foreseeable future. In March 2011, the works ground to a halt because of the revolution[2][3] with no news when or even if they would resume.

Tanzania, Kenya and Uganda

Tanzania, Kenya and Uganda are odd men in the 1,067 mm (3 ft 6 in) South & East zone as they use 1,000 mm (3 ft 3 38 in) gauge.

The latest plans for a greatly expanded railway with links to adjoining countries are to build new lines in standard gauge and possibly upgrade and convert existing metre gauge lines to the same wider gauge.[4]

Zambia

Iron ore railways

Heavy duty iron ore railways in Africa carry much more traffic than ordinary railways so they almost always adopt standard gauge to make use of proven off the shelf technology. New such lines are looming in Cameroon, Senegal and Guinea. Gabon is already 1,435 mm (4 ft 8 12 in). The Transguinean Railways is proposed to be standard gauge. Some standard gauge lines in Liberia are to be restored. An isolated 3 ft 6 in (1,067 mm) gauge line in Sierra Leone is to be converted to standard gauge

Conferences

Timeline

2010

2007

Related organisations

Similar organisations

See also

References

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