South African Class 6H 4-6-0

South African Class 6H 4-6-0
Ex CGR Class 6 609, renumbered to CGR 549, SAR Class 6H 631
Type and origin Power type Steam Designer Cape Government Railways Builder Neilson, Reid & Company Serial number 5871-5891 Model CGR Class 6 Build date 1901 Total produced 21
Specifications Configuration: ​  • Whyte 4-6-0 “Ten-wheeler” (USA) Gauge 3 ft 6 in (1,067 mm) Cape gauge Leading dia. 28.5 in (724 mm) Driver dia. 54 in (1,370 mm) Wheelbase Engine 20 ft 8 in (6.299 m) With tender 45 ft 8.5 in (13.932 m) Length 52 ft 11.75 in (16.148 m) Height 12 ft 10 in (3.912 m) Axle load 12.55 long tons (12.75 t) on each driver Adhesive weight 37.65 long tons (38.25 t) Loco weight 48.35 long tons (49.13 t) Total weight 91.4 long tons (92.9 t) Tender type XF (Permissible types XC, XC1, XD, XE, XE1, XF, XF1, XF2, XJ, XM, XM1, XN2, XM3, XM4, XP1, XS) Fuel type Coal Firebox: ​  • Grate area 18 sq ft (1.672 m2) Boiler 4 ft 6 in (1.372 m) int dia 11 ft 2 in (3.404 m) int length Boiler pressure 180 psi (1,240 kPa) Heating surface: ​  • Firebox 115 sq ft (10.684 m2)  • Tubes 188 tubes 1.875 in (47.6 mm) ext dia 1,015 sq ft (94.297 m2)  • Total surface 1,130 sq ft (104.980 m2) Cylinders Two Cylinder size 17 in (432 mm) bore 26 in (660 mm) stroke Valve gear Stephenson
Performance figures Tractive effort At 75% boiler pressure: * 18,780 lbf (83.538 kN) at 180 psi (1,240 kPa) * 17,740 lbf (78.911 kN) at 170 psi (1,170 kPa)
Career Number in class 21 Delivered 1901 First run 1901 Withdrawn 1973 Disposition Retired

Type XF Tender
Type and origin Build date 1901-1912
Specifications Bogies 2 axle Wheel diameter 34 in (864 mm) Wheelbase 14 ft 7 in (4.445 m) Length 22 ft 2.5 in (6.769 m) Axle load 10.08 long tons (10.242 t) each Tender weight 44,032 lb (19.973 t) empty 43.05 long tons (43.74 t) w/o Fuel capacity 10 long tons (10 t) Water cap. 3,000 imp gal (14,000 L)

In 1901 21 Class 6 4-6-0 steam locomotives were placed in service by the Cape Government Railways (CGR), built to the older Class 6 designs with plate frames. In 1912, when they were assimilated into the South African Railways (SAR), later renamed Spoornet and then Transnet Freight Rail (TFR), they were renumbered and reclassified to Class 6H.

Manufacturer

The Class 6 was designed at the Salt River works of the Cape Government Railways (CGR) at the same time as the Class 7. While the Class 7 was conceived primarily as a goods locomotive, the Class 6 was intended to be its fast passenger service counterpart.

These 21 Class 6 locomotives that were placed in service by the CGR in 1901 were built by Neilson, Reid and Company. With these locomotives, CGR Chief Locomotive Superintendent H.M. Beatty kept to the older plate frame design, but fitted the larger type of cab. These locomotives also reverted to the 17 inches (432 millimetres) diameter cylinders that were used on all previous Class 6 locomotives with the exception of the Class 6G. Another similarity to the early Class 6 locomotives was the visually obvious distinguishing feature of lower running boards with driving wheel fairings.

Nine of them were numbered 278 to 286 and allocated to the Western System. The other twelve were numbered 601 to 612 for the Midland System, but later renumbered 541 to 552.

Drummond tubes

One of these 21 locomotives, the Western System’s no. 286, was an experimental engine equipped with Drummond water tubes in the firebox and a very large panelled cab. Drummond tubes involved the installation of cross-water tubes in the firebox, as featured on the London and South Western Railway’s T9 Class and L11 Class, in an attempt to increase the heat surface area of the water, albeit at the cost of increased boiler complexity. On the as built CGR 286 visual exterior evidence of the presence of Drummond tubes was the rectangular covers attached to the sides of the boiler just ahead of the cab.

In service, it was found that the tubes did not affect the steaming capacity of the boiler to any significant extent. Instead, the tubes were inclined to leak and were difficult to maintain. It was therefore not long before the tubes were removed, and at the same time the cab was changed to the standard type employed on the other twenty locomotives.

Class 6 sub-classes

When these locomotives were assimilated into the newly established South African Railways (SAR) in 1912, they were renumbered 614 to 634 and reclassified to Class 6H. The rest of the CGR’s Class 6 locomotives, together with Class 6 locomotives that were inherited from the Oranje-Vrijstaat Gouwermentspoorwegen (OVGS) via the Imperial Military Railways (IMR) and the Central South African Railways (CSAR), as well as the CSAR’s own Classes 6-L1 to 6-L3, were grouped into thirteen more sub-classes by the SAR, the 4-6-0 locomotives becoming SAR Classes 6, 6A to 6G and 6J to 6L, the 2-6-2 locomotives becoming Class 6Y and the 2-6-4 locomotives becoming Class 6Z.

Service

The Class 6 series of locomotives were introduced primarily as passenger engines, but when the class became displaced by larger and more powerful locomotive classes, it literally became a “Jack-of-all-trades” that 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.

In Cape Town they held a monopoly over the suburban services until electrification arrived in 1928, and on the Reef they also worked these services between Randfontein and Springs until the loads became too heavy for them. They were employed on branch lines all over the country, Natal excluded, and practically every big station and many smaller ones had its quota of these handy locomotives to work the local passenger, goods and shunting services.

Like the Class 7, the Class 6 family gave good service for many years. By the time the last ones were retired in 1973, the Class 6 series had achieved a service life of eighty years, a performance that can be matched by few, if any, other locomotive classes world wide.

Renumberings

The table shows the Class 6H works numbers and renumberings.

Class 6H 4-6-0
Works numbers & renumbering

Works no	CGR no	CGR Renumber	SAR no
5883	278		614
5884	279		615
5885	280		616
5886	281		617
5887	282		618
5888	283		619
5889	284		620
5891	285		621
5890	286		622
5871	601	541	623
5872	602	542	624
5873	603	543	625
5874	604	544	626
5875	605	545	627
5876	606	546	628
5877	607	547	629
5878	608	548	630
5879	609	549	631
5880	610	550	632
5881	611	551	633
5882	612	552	634

Commemoration

File:RSA SACC 547 1983-04-27 25c Class 6H 627.jpg

SAR Class 6H 627

A 25c postage stamp depicting a Class 6H locomotive was one of a set of four commemorative postage stamps that were issued by the South African Post Office on 27 April 1983, to commemorate the steam locomotives of South Africa that were rapidly being withdrawn from service at the time. The artwork and stamp design was by the noted stamp designer and artist Hein Botha.

The particular locomotive depicted is ex CGR (Midland System) Class 6 605, renumbered to CGR 545 and later SAR Class 6H 627, that was withdrawn from service in 1971 and plinthed at the Mafikeng Museum in 1972. The outline of a traditional SAR locomotive number plate was used as a commemorative cancellation for De Aar on the date of release.

Gallery

The main picture shows CGR (Midland System) Class 6 609, renumbered to CGR 549 and later SAR Class 6H 631, in Cape Town.

Ex CGR (Midland System) Class 6 601, renumbered to CGR 541 and later SAR Class 6H 623

See also

• South African Class 6 4-6-0
• South African Class 6A 4-6-0
• South African Class 6B 4-6-0
• South African Class 6C 4-6-0
• South African Class 6D 4-6-0
• South African Class 6E 4-6-0
• South African Class 6F 4-6-0
• South African Class 6G 4-6-0
• South African Class 6J 4-6-0
• South African Class 6K 4-6-0
• South African Class 6L 4-6-0
• South African Class 6Y 2-6-2
• South African Class 6Z 2-6-4
• Tender locomotive numbering and classification
• Cape Government Railways
• The 4-6-0 “Ten-wheeler”
• List of South African locomotive classes