South African Class 31-000
|South African Class 31-000
Ex South African Class 1-DE
No. 31-028 (D727) at Bellville Depot, 31 October 2010
|Serial number||33507-33551 |
|AAR wheel arr.||B-B|
|Gauge||3 ft 6 in (1,067 mm)|
|Wheel diameter||915 mm (36.0 in)|
|Wheelbase||2.438 m (8 ft 0 in) per bogie
10.118 m (33 ft 2.3 in) total
|Length||15.150 m (49 ft 8.5 in)|
|Width||2.780 m (9 ft 1.4 in)|
|Height||3.916 m (12 ft 10.2 in)|
|Axle load||18,900 kg (41,700 lb)|
|Locomotive weight||74,000 kg (163,000 lb) average
76,600 kg (168,900 lb) permissible
|Fuel type||Fuel oil|
|Fuel capacity||3,000 litres (660 imp gal; 790 US gal)|
|Prime mover||Cooper-Bessemer FVBL-8|
|Engine RPM range||400 rpm idle
535 rpm high idle
1,000 rpm maximum
|Engine type||4 stroke diesel|
|Aspiration||Cooper-Bessemer ET13 turbocharger|
|Generator||DC 10 pole GE 5GT-581C3|
|Traction motors||Four GE 5GE-761A4 DC 4 pole
* 600A rating 1 hour
* 590A rating continuous
at 16 km/h (9.9 mph)
|Transmission||94/17 gear ratio (???)|
|Multiple working||3 maximum|
|Top speed||90 km/h (56 mph)|
|Power output||985 kW (1,321 hp) starting
895 kW (1,200 hp) continuous
|Tractive effort||181 kN (41,000 lbf) starting
145 kN (33,000 lbf) continuous
at 18 km/h (11 mph)
|25% starting, 20% continuous|
|Locomotive brake||6-SLAV-1 with vigilance control
Not equipped with dynamic brakes
|65% ratio at 345 kPa (50.0 psi) brake cylinder pressure|
|Train brakes||700 litres (180 US gal) main reservoir
Compressor capacity at high idle: 0.039 m3/s (1.4 cu ft/s)
Exhauster capacity at high idle: 0.155 m3/s (5.5 cu ft/s)
|Safety systems||Two station controls|
|Railroad(s)||South African Railways
|Number in class||45|
|Number||31-001 to 31-045 (D700-D744)|
|Delivered||June to July 1958|
|First run||1958 |
In June and July 1958 the South African Railways placed forty-five Class 1-DE General Electric type U12B diesel-electric locomotives in service. They were later reclassified to Class 31-000 and renumbered.
The South African Class 31-000 type GE U12B diesel-electric locomotive was designed for the South African Railways (SAR) and built by General Electric in 1958 and imported. They were the first diesel-electric road locomotives to enter SAR service in quantity.
Reclassification & renumbering
Upon delivery, they were classified as Class 1-DE and numbered in the range from D700 to D744. When the SAR adopted a new classification and numbering system for electric and diesel powered locomotives circa 1960, they were reclassified to Class 31-000 and renumbered in the range from 31-001 to 31-045.
The Class 31-000 is a high short hood locomotive. While the short hood end is usually considered as the front end, the cab is equipped with dual station controls to make it fully bidirectional.
They were placed in service working out of Johannesburg to Kroonstad in the Free State and to Volksrust on the mainline to Natal. By the 1980s they were relegated to shunting and pickup service on the Reef and at some other major centres.
Of the original forty-five locomotives, forty survived into the Spoornet era in the 1990s. Now retired from Spoornet service, some still see service in private hands. Three of them, 31-001 (D700), 31-005 (D704) and 31-038 (D737), were acquired by Sheltam for use at Rand Uranium near Randfontein and at Welkom. The first two were converted to low short hood locomotives and were still in service in 2010, while the third was used for spare parts.
The Class 31-000 builder’s works numbers, renumbering and disposition are set out in the table.
Some of the liveries applied to Class 31-000 locomotives are illustrated below.
Sheltam no. 1201, ex SAR no. 31-005 (D704), 19 May 2010
No. 31-007 (D706) at Bellville Depot,
10 January 2009
- 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. 38, 45.
- South African Railways Index and Diagrams Electric and Diesel Locomotives, 610 mm and 1065 mm Gauges, Ref LXD 14/1/100/20, 28 January 1975, as amended
- Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 137–138. ISBN 0869772112.