South African Class 6D 4-6-0

This article is about one of several different Cape Government Railways locomotive types to be designated "6th Class". For the others, see Cape Government Railways 6th Class locomotives.

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: ​  • Whyte 4-6-0 (Tenwheeler)  • UIC 2'Cn2 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) ​  • Axle spacing (Asymmetrical) 1-2: 4 ft 9 in (1,448 mm) 2-3: 6 ft 7 in (2,007 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) 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  • Grate 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: ​  • Firebox 107 sq ft (9.9 m2)  • Tubes 1,015 sq ft (94.3 m2)  • Total surface 1,122 sq ft (104.2 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.

Manufacturer

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.

H.M. Beatty

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.

Class 6 sub-classes

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.

When these locomotives were assimilated into the South African Railways (SAR) in 1912, they were renumbered in the range from 565 to 597 and designated Class 6D. The rest of the CGR's 6th Class locomotives, together with the Class 6-L1 to 6L3 locomotives which had been inherited by the Central South African Railways from the Oranje-Vrijstaat Gouwerment-Spoorwegen via the Imperial Military Railways, were grouped into thirteen more sub-classes by the SAR. The 4-6-0 locomotives became SAR Classes 6, 6A to 6C, 6E to 6H and 6J to 6L, the 2-6-2 locomotives became Class 6Y and the 2-6-4 locomotives became Class 6Z.

Service

South Africa

The Class 6 series of locomotives were introduced primarily as passenger locomotives, but when the class became displaced by larger and more powerful locomotive classes, it literally became a Jack-of-all-trades which proved itself as one of the most useful and successful locomotive classes ever to be designed at the Salt River shops. It went on to see service in all parts of the country, except Natal, and was used on all types of traffic.

After the Simon's Town line in Cape Town was electrified in 1928, Class 6D engines that used to haul commuters on this line became dock shunting engines in Table Bay Harbour. This continued until they were gradually replaced by new Class S2 0-8-0 shunting engines from 1952.

Sudan

During the Second World War, sixteen locomotives of the Classes 6 to 6D were transferred to the Middle East to assist with the war effort during the North African Campaign. The two Class 6D locomotives in this group were numbers 572 and 587. They did not return to South Africa after the war and were sold to the Sudan Railways Corporation in 1942. Sudan Railways renumbered them M714 and M715, in the same order as their former SAR engine numbers.

Renumbering

The Class 6D works numbers, system allocation and renumbering are listed in the table.

Class 6D 4-6-0
Works numbers and renumbering

Works no.	CGR no.	CGR system	SAR no.	Sudan no.
5240	234	Western	565
5241	235	Western	566
5242	236	Western	567
5245	237	Western	568
5246	238	Western	569
5247	239	Western	570
5249	240	Western	571
5250	241	Western	572	M714
5251	242	Western	573
5252	243	Western	574
5257	244	Western	575
5258	245	Western	576
5259	246	Western	577
5260	247	Western	578
5261	248	Western	579
5262	249	Western	580
5263	250	Western	581
5264	251	Western	582
5265	252	Western	583
5266	253	Western	584
5267	254	Western	585
5268	255	Western	586
5269	256	Western	587	M715
5270	257	Western	588
5271	258	Western	589
5272	259	Western	590
5248	585	Midland	591
5253	586	Midland	592
5255	594	Midland	593
5243	665	Eastern	594
5244	666	Eastern	595
5254	667	Eastern	596
5256	668	Eastern	597

Preservation

Only one of these locomotives survives. No. 579 is plinthed at King William's Town Station Forecourt.