CGR 5th Class 4-6-0 1891

CGR 5th Class 4-6-0 1891
OVGS 5th Class K 4-6-0 1891
South African Class 05 4-6-0 1891

CGR no. 122, SAR no. 0122, c. 1920

Type and origin Power type Steam Designer Cape Government Railways (Michael Stephens) Builder Dübs and Company Serial number 2712-2741 Model CGR 5th Build date 1891 Total produced 30

Specifications Configuration 4-6-0 (Tenwheeler) Driver 2nd coupled axle Gauge 3 ft 6 in (1,067 mm) Cape gauge Leading dia. 28 in (711 mm) Coupled dia. 49 in (1,245 mm) Tender wheels 37 inches (940 mm) Wheelbase 40 ft 2 3⁄8 in (12,252 mm)  • Engine 19 ft 1 3⁄8 in (5,826 mm)  • Leading 5 ft (1,524 mm)  • Coupled 10 ft (3,048 mm)  • Tender 10 ft (3,048 mm) Wheel spacing (Asymmetrical) 1-2: 4 ft 6 in (1,372 mm) 2-3: 5 ft 6 in (1,676 mm) Length: ​  • Over couplers 48 ft 1 3⁄4 in (14,675 mm) Height 12 ft 1 1⁄2 in (3,696 mm) Axle load 10 LT 8 cwt (10,570 kg)  • Leading 7 LT 15 cwt (7,874 kg)  • 1st coupled 10 LT 8 cwt (10,570 kg)  • 2nd coupled 10 LT 8 cwt (10,570 kg)  • 3rd coupled 9 LT 15 cwt (9,906 kg) Loco weight 38 LT 6 cwt (38,910 kg) Tender weight 28 LT 11 cwt (29,010 kg) Total weight 66 LT 17 cwt (67,920 kg) Tender type 3-axle Fuel type Coal Fuel capacity 4 LT (4.1 t) Water cap 1,950 imp gal (8,860 l) Firebox type Round-top, as built Belpaire, by CSAR  • Firegrate area 16.18 sq ft (1.503 m2) Boiler: ​  • Pitch 6 ft 4 1⁄2 in (1,943 mm)  • Diameter 4 ft (1,219 mm)  • Tube plates 11 ft 1 7⁄8 in (3,400 mm)  • Small tubes 185: 1 3⁄4 in (44 mm) Boiler pressure 150 psi (1,034 kPa) Safety valve Ramsbottom Heating surface 1,037.28 sq ft (96.366 m2)  • Tubes 946.32 sq ft (87.916 m2)  • Firebox 90.96 sq ft (8.450 m2) Cylinders Two Cylinder size 16 in (406 mm) bore 24 in (610 mm) stroke Valve gear Stephenson Couplers Johnston link-and-pin

Performance figures Tractive effort 14,110 lbf (62.8 kN) @ 75%

Career Operators Cape Government Railways OVGS New Cape Central Railway Imperial Military Railways Central South African Railways South African Railways Class CGR 5th Class, SAR Class 05 Number in class 30 Numbers Eastern 55-58 Midland 136-138 & 309-314 Western 117-118, 121-135 Delivered 1891 First run 1891 Withdrawn 1953

The Cape Government Railways 5th Class 4-6-0 of 1891 was a South African steam locomotive from the pre-Union era in the Cape of Good Hope.

In 1891, the Cape Government Railways placed a second batch of thirty 5th Class tender locomotives with a 4-6-0 Tenwheeler type wheel arrangement in mainline service on all three Cape Systems. They were similar to the previous batch of 1890, but differed in respect of the diameter of their coupled wheels, the length of their smokeboxes and their tractive effort.

The second batch of Cape Government Railways (CGR) 5th Class 4-6-0 Tenwheeler type tender locomotives was delivered from Dübs and Company in 1891.

Of the thirty locomotives, four went to the Eastern System to work out of East London, numbered in the range from 55 to 58, nine went to the Midland System to work out of Port Elizabeth, numbered in the ranges from 136 to 138 and 309 to 314, and seventeen went to the Western System for service between Touws River and Beaufort West, numbered 117, 118 and in the range from 121 to 135.

The order had originally been for 36 locomotives. In 1891, a complete design for a new 7th Class 4-8-0 Mastodon type locomotive was prepared at the Salt River works in Cape Town. The last six locomotives of the order were cancelled and substituted with an order for six of these new 7th Class locomotives.

While the 1891 locomotive was identical to the batch of 1890 in most respects, it differed in three aspects.

In the 1890s, some improvements to smokebox design took place. Extending the smokebox forward increased its volume. The increased amount of exhaust gases present in the smokebox had the effect of stabilising and improving the draught. The date of this improvement can be pinned to the introduction of this second batch of 5th Class locomotives with their lengthened smokeboxes. This had such a profound effect on the boiler’s steaming ability that virtually every serving locomotive on the CGR and Natal Government Railways (NGR) had their smokeboxes extended.

The 5th Class was considered to be the first really efficient all-round locomotive in the Cape of Good Hope. It was used on all kinds of traffic, wherever the mainline had severe gradients and curves.