South African Class 12E

From Wikipedia, the free encyclopedia
Jump to: navigation, search
South African Class 12E
SAR Class 12E 12-003.jpg
No. 12-003 at Koedoespoort, Pretoria, 2 October 2009
Type and origin
Power type Electric
Designer Union Carriage & Wagon
Builder Union Carriage & Wagon
Model UCW 12E
Build date 1982-1983
Total produced 5
Specifications
AAR wheel arr. B-B
UIC class Bo'Bo'
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Wheel diameter 1,220 mm (48.0 in)
Wheelbase 11,278 mm (37 ft 0 in)
 • Bogie 3,430 mm (11 ft 3.0 in)
Pivot centres 7,848 mm (25 ft 9.0 in)
Panto shoes 7,731 mm (25 ft 4.4 in)
Length:
 • Over couplers 15,522 mm (50 ft 11.1 in)
 • Body 14,630 mm (48 ft 0 in)
Width 2,896 mm (9 ft 6.0 in)
Height:
 • Pantograph 4,127 mm (13 ft 6.5 in)
 • Body height 3,937 mm (12 ft 11.0 in)
Axle load 20,900 kg (46,100 lb)
Adhesive weight 83,600 kg (184,300 lb)
Loco weight 83,600 kg (184,300 lb)
Power supply Catenary
Current collection Pantographs
Traction motors Four AEI-283AY
 • Rating 1 hour 623 kW (835 hp)
 • Continuous 563 kW (755 hp)
Gear ratio 23:66
Loco brake Air & Regenerative
Train brakes Air
Couplers AAR knuckle
Performance figures
Maximum speed 150 km/h (93 mph)
Power output:
 • 1 hour 2,492 kW (3,342 hp)
 • Continuous 2,252 kW (3,020 hp)
Tractive effort:
 • Starting 240 kN (54,000 lbf)
 • 1 hour 170 kN (38,000 lbf)
 • Continuous 149 kN (33,000 lbf)
Career
Operators South African Railways
Spoornet
Transnet Freight Rail
Class Class 12E
Power class 3 kV DC
Number in class 5
Numbers 12-001 - 12-005
Delivered 1983
First run 1983

The South African Railways Class 12E of 1983 was an electric locomotive.

On 11 January 1984, the South African Railways inaugurated the MetroBlitz high speed interurban train service between Pretoria and Johannesburg. Five Class 12E electric locomotives with a Bo-Bo wheel arrangement, which entered service in 1983, were designed and built specifically for the MetroBlitz.[1][2]

Manufacturer[edit]

The 3 kV DC Class 12E electric passenger locomotive was designed and built for the South African Railways (SAR) by Union Carriage & Wagon (UCW) in Nigel, Transvaal, with the electrical equipment supplied by General Electric Company (GEC). It is a modified single-cab version of the Class 6E1, Series 10 locomotive and was specially designed and built for use with the MetroBlitz, a high speed passenger commuter train which, with effect from 16 January 1984, ran daily between Pretoria and Johannesburg.[3]

Five locomotives were delivered by UCW in 1983, numbered in the range from 12-001 to 12-005. UCW did not allocate builder's numbers to the locomotives which it built for the SAR, but used the SAR unit numbers for their record keeping.[1]

Characteristics[edit]

Appearance[edit]

SAR Class 12E 12-003 ID.JPG

Based on the dual cab Class 6E1 locomotive, the Class 12E is a single-cab locomotive with a conductor's cabin at the rear end. They were used with specially designed suburban passenger coaches, which rode on air-sprung disk-braked high speed bogies. The MetroBlitz operated with two locomotives per train, one locomotive at each end, which made dual cabs unnecessary.[1][4]

Bogies[edit]

Like the Class 6E1, the Class 12E was built with sophisticated traction linkages on their bogies. Together with the locomotive's electronic wheel-slip detection system, these traction struts, mounted between the linkages on the bogies and the locomotive body and colloquially referred to as grasshopper legs, ensure the maximum transfer of power to the rails without causing wheel-slip, by reducing the adhesion of the leading bogie and increasing that of the trailing bogie by as much as 15% upon starting. This feature is controlled by electronic wheel-slip detection devices and an electric weight transfer relay, which reduce the anchor current to the leading bogie by as much as 50A in notches 2 to 16.[4]

Traction[edit]

The Class 12E has the same power output as a Class 6E1, but with a higher gear ratio of 23:66, compared to the 18:67 of the Class 6E1. This enabled it to run at a safe maximum speed of 150 kilometres per hour (93 miles per hour). Since it was designed for suburban service, sanding gear was deemed unnecessary and was not installed on the Class 12E. This turned out to be a disadvantage, when they were eventually allocated to mainline service to haul the Blue Train.[1][4]

Service[edit]

When the MetroBlitz was introduced, it was planned to implement similar high speed services at other major centres and also to expand the Pretoria-Johannesburg service, to run through to other centres like Bloemfontein in the Free State, a trip which was calculated to be possible in as little as three and a half hours at high speed.[2]

The MetroBlitz service was discontinued after a few years, however, with its demise being blamed on poor cost recovery. Other major factors in the failure of the high speed service, was the disruption which was caused to other train traffic which shared the same line and which had to have their schedules adapted to accommodate the MetroBlitz, as well as the inability to operate at its full potential speed as a result of having to share the line.[5]

Liveries[edit]

MetroBlitz[edit]

The Class 12E was delivered in a special livery for the Metroblitz, gray all over with a red pilot and lower sides, in line with the red lower sides on the passenger coaches. It had yellow and red whiskers wrapped around to the sides and tapering off towards the rear, and two tapered yellow lines on the sides in line with the yellow lines above and beneath the windows on the coaches.[2]

The Blue Train[edit]

In the SAR and Spoornet eras, when the official liveries were Gulf Red and yellow whiskers for the SAR, and initially orange and later maroon for Spoornet, many selected electric locomotives and some diesel-electrics were painted blue for use with the Blue Train, but without altering the layout of the various paint schemes. Blue Train locomotives were therefore blue with yellow whiskers in the SAR era, blue with the Spoornet logo and the name "SPOORNET" in Spoornet's orange era, and blue with the Spoornet logo, but without the name "SPOORNET", in Spoornet's maroon era. Later, in Spoornet's blue era, there was no need for a separate Blue Train livery, while in the Transnet Freight Rail (TFR) era one Class 14E and the surviving Class 14E1 electric locomotives were eventually repainted in blue during 2012 for use with the Blue Train.[5][6][7]

After the MetroBlitz service came to an end in 1985, the five Class 12E locomotives were repainted blue with yellow whiskers and replaced Class 6E1 numbers E1341 to E1345 as Blue Train locomotives between Pretoria and Kimberley. Probably at the same time, their original solid pilots were replaced with pilots with a pattern of holes, similar to those used on the Class 5E and Class 6E families, but slanted back towards the front bogies.[1][5]

They continued to work the Blue Train between Johannesburg and Kimberley until about 2005, when that function was taken over by the dual voltage Classes 14E and 14E1, which subsequently worked the Blue Train over the full distance between Johannesburg and Cape Town, as well as on other electrified routes. All five Class 12E locomotives were then staged at the Koedoespoort shops in Pretoria.[5]

Disposal[edit]

During June 2012, all five locomotives were put up for auction in a single lot at a starting price of R424,000. They were apparently not sold, however, since they were observed to be still at Koedoespoort during 2014.[8]

The Gautrain[edit]

The MetroBlitz linked Pretoria and Johannesburg with a travelling time of 42 minutes, reaching speeds of 160 kilometres per hour (99 miles per hour) while having to contend with other mixed traffic on 3 ft 6 in (1,067 mm) Cape gauge track. This was a remarkable feat, considering that twenty-seven years later, the Gautrain, the dedicated high speed commuter train which was introduced two years later than planned in 2011, linked Pretoria and Johannesburg with a travelling time of 40 minutes, reaching speeds of 160 kilometres per hour (99 miles per hour) on dedicated 4 ft 8 12 in (1,435 mm) broad gauge track.[9]

Illustration[edit]

The main picture and those following, serve to illustrate the Class 12E locomotive from all sides, as well as some of the liveries which were applied to it.

References[edit]

  1. ^ a b c d e 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 Die Vaderland, Donderdag 12 Januarie 1984, p. 3
  3. ^ "UCW - Electric locomotives" (PDF). The UCW Partnership. Archived from the original (PDF) on 12 October 2007. Retrieved 30 September 2010. 
  4. ^ a b c Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 128–129, 133–134. ISBN 0869772112. 
  5. ^ 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, 60. 
  6. ^ E1973 in blue based on orange livery
  7. ^ E1951 in blue based on maroon livery
  8. ^ GoIndustry DoveBid Online Auction, Transnet Freight Rail, Lots closing from 5 Jul 2012
  9. ^ Railways Africa, 18 Jun 2010: Latest Transnet Freight Rail Auction

External links[edit]

External video
High Speed on SA Transport Services & World Record on test A short video of the world record test run of 245 km/h on Cape gauge and the first high speed daily train service between Pretoria and Johannesburg, the MetroBlitz, which operated during 1984 (15 minutes 19 seconds)