South African Class 18E, Series 2

Beginning in 2000 Spoornet embarked on a program to rebuild Class 6E1, Series 6 to Series 11 locomotives to Class 18E, Series 1 locomotives. Most of the Class 6E1s that had previously been reclassified or modified to Class 16E or Class 17E were rebuilt to Class 18E as well.^[2]

The rebuilding of Class 6E1, Series 6 to Series 8 locomotives to Class 18E, Series 2 locomotives commenced in 2009, with running numbers starting from 18-600. During 2010 Class 6E1, Series 5 or even older Class 6E1 locomotives began to be selected for rebuilding.^[2]

Manufacturer

The South African Class 6E1 3 kV DC electric locomotive was built for the South African Railways (SAR) by Union Carriage and Wagon (UCW) in Nigel, Transvaal, with the electrical equipment supplied by the General Electric Company (GEC). UCW did not allocate builder’s numbers to the locomotives it built for the SAR. While usual practice by most other locomotive builders was to allocate builder’s numbers or works numbers to record the locomotives built by them, UCW simply used the SAR running numbers for their record keeping.^[3]

Rebuilding to Class 18E, Series 1 locomotives ceased in 2009 with four hundred and forty-six units rebuilt, the last Series 1 locomotive being number 18-525. The rebuilding to Class 18E, Series 2 commenced in 2009 and was done by Transnet Rail Engineering (TRE), at its Koedoespoort shops in Pretoria, Gauteng. The Series 2 running number sequence starts from 18-600 and by 26 October 2011 numbers as high as 18-667 had been observed in service.^[2][4]

Features

Orientation

The Class 6E1 that it was rebuilt from, is a dual cab locomotive and has a roof access ladder on one side only, just to the right of the cab access door. The roof access ladder end is marked as the number 2 end. A passage along the centre of the locomotive connects the cabs.^[1]

The rebuilt Class 18E locomotive, on the other hand, is a single cab unit since the number 1 end cab was stripped of all controls during the rebuilding, to have additional equipment and a toilet installed to accommodate female crew.^[1][4][5]

Equipment

The rebuild includes the installation of Alsthom micro-processor control technology. New equipment in the totally refurbished Class 18E locomotive include:^[4]

• Dual-purpose main resistance modules that replaced the accelerating resistance system and that are used for motoring and rheostatic braking.
• A transducer to relay vacuum and compressed air pressure to an electric signal.
• A DC current transformer (DCCT) that measures the current flowing to and from certain equipment such as the traction motors, or total overhead line current.
• A potential divider to measure the voltage in the overhead equipment and traction motors.
• A main processor unit (MPU), located in high tension compartment 1, used for primary (master) control of the locomotive.
• Remote input-output modules (RIOM) located in high tension compartment 2, in the low tension panel and the driving compartment, used for secondary (slave) control of the locomotive.
• Two digital display units (DDU) mounted on the driving console to display, for example, information like speed, current draw and available overhead voltage, current draw of the traction motors in each bogie, rheostatic braking current generated per bogie, as well as performance information about all the locomotives in the consist.
• Overspeed protection that will automatically open the line switches if any pair of wheels slips and a speed of 95 kilometres per hour (59 miles per hour) is exceeded.^[5]

Identifying features

The most obvious visual feature to distinguish the Class 18E from the Class 6E1 is the filled in driver’s windows at the rear end where the toilet is installed. The remaining rear windscreen still has the slanted upper edge of the 6E1 windscreens, but the new front windscreens on the Class 18E are rectangular.^[5]

On the sides, obvious visual distinctions from the Class 6E1 are the left one of the two large grilles that was removed, with the opening filled in, two new large grilles that are installed in the centre lower sides to serve as air intakes for the rheostatic braking resistance blowers, and a large access door to one of the high-tension compartments that is installed in place of the rightmost small window that was in the upper side of the Class 6E1. On the left side, the air intakes for the air conditioner in the cab are installed between the top three steps of the roof access ladder.^[5]

Locomotives rebuilt from Class 6E1, Series 7 or earlier models have a pipe sunk into a recess that runs along the left half of the lower edge of the body on the locomotive’s right side, the side opposite the roof access ladder side. On locomotives rebuilt from Class 6E1, Series 8 this pipe could be routed out of sight internally.

Lineage identification

All features that distinguished Class 6E1, Series 8 or older locomotives from each other are still present on the Class 18E rebuilds, making it possible to visually determine the Class 6E1 origin of Class 18E locomotives. Examples are shown in the gallery below.^[1]

• The side doors with:

• mid door mounted door handles on ex Series 3 to early Series 7 locomotives; and
• low mounted handles with a mid door drawer pull type handle at mid door level on ex late Series 7 to Series 8 locomotives.

• On ex Series 8 locomotives, the large hatch door on each side, below the second small window to the right of the side door on the roof access ladder side, and below the first window immediately to the right of the door on the opposite side.
• On ex Series 6 and 7 locomotives, the smooth sides and the rainwater beading above the small grilles on the sides just to the right of the side doors and, on the Class 18E rebuilt from these, the recessed pipe on the right side. On some locomotives that are shown in the dated rebuilding list below as being ex Series 6 locomotives, however, this beading is absent, either because it had been removed for some reason or because a specific locomotive that had been earmarked for rebuilding had been found unsuitable and was replaced by a Series 5 or earlier locomotive. Examples are numbers 18-620 and 18-636.
• On ex Series 3 to 5 locomotives, the absence of the rainwater beading above the small grilles on the sides just to the right of the side doors and, on the Class 18E, the recessed pipe on the right side.

Table of Rebuilds

The table shows the original Class 6E1 number for the first thirty-seven Class 18E, Series 2 as well as the date on which it was released back into service after rebuilding, where known. Information about running numbers 18-637 and later is unavailable as yet.^[2][4]

Gallery

Rebuilt from Series 5 or older

Rebuilt from Series 6

Rebuilt from Series 7

See also

• South African Class 6E1, Series 5
• South African Class 6E1, Series 6
• South African Class 6E1, Series 7
• South African Class 6E1, Series 8
• South African Class 16E
• South African Class 17E
• South African Class 18E, Series 1
• Electric locomotive numbering and classification
• List of South African locomotive classes

References

1. ^ ^{a b c d} South African Railways Index and Diagrams Electric and Diesel Locomotives, 610mm and 1065mm Gauges, Ref LXD 14/1/100/20, 28 January 1975, as amended
2. ^ ^{a b c d} Information gathered from the rebuild files of individual locomotives at Transnet Rail Engineering’s Koedoespoort shops
3. ^ "UCW - Electric locomotives". The UCW Partnership. Archived from the original on 12 October 2007. http://web.archive.org/web/20071012023401/http://www.ucw.co.za/pdf/electric_loco.pdf. Retrieved 30 September 2010. 
4. ^ ^{a b c d} Middleton, John N. (2002). Railways of Southern Africa Locomotive Guide - 2002 (as amended by Combined Amendment List 4, January 2009) (2nd, Dec 2002 ed.). Herts, England: Beyer-Garratt Publications. pp. 49, 51, 57-58. 
5. ^ ^{a b c d} 18E Locomotive (TFR leaflet used in driver training, circa 2010)