South African Class 6D 4-6-0

CGR 6th Class 4-6-0 1898
South African Class 6D 4-6-0

CGR Eastern System 6th Class no. 665, SAR Class 6D no. 594, Sydenham Loco, 29 December 1965

Type and origin ♠ Original locomotive, as built ♥ Reboilered locomotive Power type Steam Designer Cape Government Railways (H.M. Beatty) Builder Neilson, Reid and Company Serial number 5240-5272 Model CGR 6th Class Build date 1898 Total produced 33

Specifications Configuration 4-6-0 (Tenwheeler) Driver 2nd coupled axle Gauge 3 ft 6 in (1,067 mm) Cape gauge Leading dia. 28 1⁄2 in (724 mm) Coupled dia. 54 in (1,372 mm) Tender wheels 37 in (940 mm) Wheelbase 42 ft 8 5⁄8 in (13,021 mm)  • Engine 20 ft 7 3⁄4 in (6,293 mm)  • Leading 5 ft 5 1⁄2 in (1,664 mm)  • Coupled 11 ft 4 in (3,454 mm)  • Tender 10 ft (3,048 mm) Wheel spacing (Asymmetrical) 1-2: 4 ft 9 in (1,448 mm) 2-3: 6 ft 7 in (2,007 mm) Length: ​  • Over couplers 51 ft 11 5⁄8 in (15,840 mm) Height 12 ft 10 in (3,912 mm) Frame type Plate Axle load 12 LT 10 cwt (12,700 kg)  • Leading 11 LT 4 cwt (11,380 kg)  • 1st coupled 11 LT 19 cwt (12,140 kg)  • 2nd coupled 12 LT 10 cwt (12,700 kg)  • 3rd coupled 12 LT 10 cwt (12,700 kg)  • Tender axle 10 LT 8 cwt (10,570 kg) average Adhesive weight 36 LT 19 cwt (37,540 kg) Loco weight 48 LT 3 cwt (48,920 kg) Tender weight 31 LT 4 cwt (31,700 kg) Total weight 79 LT 7 cwt (80,620 kg) Tender type YC (3-axle) YB, YC, YE, YE1 permitted Fuel type Coal Fuel capacity 5 LT 10 cwt (5.6 t) Water cap 2,590 imp gal (11,770 l) Firebox type Round-top  • Firegrate area 18 sq ft (1.7 m2) Boiler: ​  • Pitch 6 ft 8 in (2,032 mm)  • Diameter 4 ft 4 in (1,321 mm)  • Tube plates 11 ft 2 1⁄8 in (3,407 mm)  • Small tubes 185: 1 7⁄8 in (48 mm) Boiler pressure ♠ 160 psi (1,103 kPa) ♥ 180 psi (1,241 kPa) Safety valve Ramsbottom Heating surface 1,122 sq ft (104.2 m2)  • Tubes 1,015 sq ft (94.3 m2)  • Firebox 107 sq ft (9.9 m2) Cylinders Two Cylinder size 17 in (432 mm) bore 26 in (660 mm) stroke Valve gear Stephenson Couplers Johnston link-and-pin AAR knuckle (1930s)

Performance figures Tractive effort ♠ 16,690 lbf (74.2 kN) @ 75% ♥ 18,780 lbf (83.5 kN) @ 75%

Career Operators Cape Government Railways South African Railways Sudan Railways Class CGR 6th Class, SAR Class 6D Number in class 33 Numbers CGR 234-259, 585, 586 & 594, 665-668 SAR 565-597 Sudan M714-M715 Delivered 1898 First run 1898 Withdrawn 1973

The South African Railways Class 6D 4-6-0 of 1898 was a steam locomotive from the pre-Union era in the Cape of Good Hope.

In 1898, a fourth batch of 33 6th Class 4-6-0 steam locomotives were placed in service by the Cape Government Railways. In 1912, when these locomotives were assimilated into the South African Railways, they were renumbered and designated Class 6D.

The original 6th Class 4-6-0 passenger steam locomotive was designed at the Salt River works of the Cape Government Railways (CGR) in 1893, at the same time as the 7th Class and both according to the specifications of Michael Stephens, at the time Chief Locomotive Superintendent of the CGR, and under the supervision of H.M. Beatty, at the time Locomotive Superintendent of the Western System.

The 33 locomotives in this fourth group of the CGR 6th Class were built in 1898 by Neilson, Reid and Company. Of these engines, 26 went to the CGR's Western System, numbered in the range from 234 to 259, three to the Midland System, numbered 585, 586 and 594, and four to the Eastern System, numbered in the range from 665 to 668.

These locomotives represented a further advance on earlier 6th Class locomotives, with a greater heating surface and a larger firegrate area. They did, however, revert to the same Type YC six-wheeled tenders which were earlier used with the second group of 6th Class locomotives, later the Class 6A.

When the Union of South Africa was established on 31 May 1910, the three Colonial government railways (CGR, Natal Government Railways and Central South African Railways) were united under a single administration to control and administer the railways, ports and harbours of the Union. Although the South African Railways and Harbours came into existence in 1910, the actual classification and renumbering of all the rolling stock of the three constituent railways were only implemented with effect from 1 January 1912.