South African Class DS

South African Class DS

300px Class DS shunting locomotive, circa 1940

Type and origin Power type Diesel-electric Designer Allgemeine Elektricitäts-Gesellschaft Builder Allgemeine Elektricitäts-Gesellschaft Model SAR DS Build date 1939 Total produced 1

Specifications AAR wheel arr B-B UIC class Bo'Bo' Gauge 3 ft 6 in (1,067 mm) Cape gauge Wheel diameter 42 in (1,067 mm) Wheelbase 8 ft 6 in (2,591 mm) per bogie 30 ft 4 in (9,246 mm) total Length 43 ft 8 in (13,310 mm) over headstocks 46 ft 6 in (14,173 mm) over couplers Height Frame 21 ft 8 in (6,604 mm) between bogie pivot centres Axle load Loco weight Fuel type Fuel oil Fuel capacity 455 imp gal (2,070 L; 546 US gal) Prime mover Two MAN 205 hp (153 kW) Engine type Diesel Generator Two AEG 110 kW (150 hp) main Two AEG 12 kW (16 hp) auxiliary Traction motors Four AEG Transmission 5.67:1 Gear ratio

Performance figures Power output 410 hp (310 kW) Tractive effort 157 kN (35,000 lbf) starting

Career Operators South African Railways Class Class DS Number in class 1 Numbers D137, renumbered D513 Delivered 1939 First run 1939 Retired 1966 Disposition Scrapped

The South African Railways Class DS of 1939 was a diesel-electric locomotive.

The first diesel-electric locomotive on the South African Railways was a single Class DS AEG diesel-electric shunting locomotive that was placed in service at the Congella yards near Durban in Natal Province in 1939.

Manufacturer

As a result of the problems experienced to obtain adequate water supplies in the arid regions of South Africa and South West Africa, particularly on the section from De Aar via Upington to Keetmanshoop, the South African Railways (SAR) decided to experiment with diesel-powered traction and introduced its first two diesel-electric shunting locomotives in 1939.

The first of these was a single twin-engined centre-cab locomotive with a Bo-Bo wheel arrangement that was ordered from Allgemeine Elektricitäts-Gesellschaft (AEG) in Berlin. The locomotive was designated Class DS and was initially numbered D137, but it was soon renumbered to D513. Both numbers were in the electric locomotive number range, but with a D for diesel instead of an E for electric prefix.

Characteristics

The locomotive was powered by two Maschinenfabrik Augsburg-Nürnberg (MAN) 205 horsepower (153 kilowatts) eight-cylinder diesel engine prime movers, one on either side of the cab. An AEG 110 kilowatts (150 horsepower) main generator and an AEG 12 kilowatts (16 horsepower) auxiliary generator were mounted directly in line between each engine and the cab. Each engine was water-cooled, with a fan that was belt-driven by its engine and that drew air through a conventional radiator.

The bogies were very similar to those of the Class 1E electric locomotive, each with two DC traction motors arranged in series. The cab was equipped with mechanically interlocked dual controls to enable operation in either direction.

Service

The locomotive was placed in service at the Congella yards near Durban. The first diesel-electric locomotive on the SAR eventually found its way to Cape Town, where it was scrapped at the Salt River Works in November 1966.

Illustration

• SAR Class DS D137 (D513).jpg

  Class DS no. D137, circa 1940