South African Class 6H 4-6-0

CGR 6th Class 4-6-0 1901 Neilson Reid South African Class 6H 4-6-0
CGR 6th Class no. 607, then no. 547, SAR Class 6H no. 629, at Midlandia Loco, Noupoort
Type and origin Power type Steam Designer Cape Government Railways (H.M. Beatty) Builder Neilson, Reid and Company Serial number 5871-5891 Model CGR 6th Class Build date 1901 Total produced 21
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 33 1⁄2 in (851 mm) as built 34 in (864 mm) retyred Wheelbase 45 ft 8 1⁄2 in (13,932 mm)  • Engine 20 ft 8 in (6,299 mm)  • Leading 5 ft 6 in (1,676 mm)  • Coupled 11 ft 4 in (3,454 mm)  • Tender 14 ft 7 in (4,445 mm)  • Tender bogie 4 ft 7 in (1,397 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 52 ft 11 3⁄4 in (16,148 mm) Height 12 ft 10 in (3,912 mm) Frame type Plate Axle load 12 LT 11 cwt (12,750 kg)  • Leading 11 LT 14 cwt (11,890 kg)  • Coupled 12 LT 11 cwt (12,750 kg)  • Tender bogie Bogie 1: 16 LT 15 cwt (17,020 kg) Bogie 2: 17 LT 8 cwt (17,680 kg)  • Tender axle 8 LT 14 cwt (8,840 kg) Adhesive weight 37 LT 13 cwt (38,250 kg) Loco weight 49 LT 7 cwt (50,140 kg) Tender weight 34 LT 3 cwt (34,700 kg) Total weight 83 LT 10 cwt (84,840 kg) Tender type XD (2-axle bogies) XC, XC1, XD, XE, XE1, XF, XF1, XF2, XJ, XM, XM1, XM2, XM3, XM4, XP1, XS permitted Fuel type Coal Fuel capacity 5 LT 10 cwt (5.6 t) Water cap 2,730 imp gal (12,400 l) Firebox type Round-top  • Firegrate area 18 sq ft (1.7 m2) Boiler: ​  • Pitch 6 ft 10 in (2,083 mm)  • Diameter 4 ft 6 in (1,372 mm)  • Tube plates 11 ft 2 1⁄8 in (3,407 mm)  • Small tubes 185: 1 7⁄8 in (48 mm) Boiler pressure 180 psi (1,241 kPa) 170 psi (1,172 kPa) adjusted Safety valve Ramsbottom Heating surface 1,130 sq ft (105 m2)  • Tubes 1,015 sq ft (94.3 m2)  • Firebox 115 sq ft (10.7 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 18,780 lbf (83.5 kN) @ 75% 17,740 lbf (78.9 kN) adjusted
Career Operators Cape Government Railways South African Railways Class CGR 6th Class, SAR Class 6H Number in class 21 Numbers CGR 278-286, 601-612 (541-552) SAR 614-634 Delivered 1901 First run 1901

The South African Railways Class 6H 4-6-0 of 1901 was a steam locomotive from the pre-Union era in the Cape of Good Hope.

In 1901, 21 6th Class 4-6-0 steam locomotives were placed in service by the Cape Government Railways, built to the older 6th Class designs with plate frames. In 1912, when they were assimilated into the South African Railways, they were renumbered and designated Class 6H.

The original Cape 6th Class locomotive was designed at the Salt River works of the Cape Government Railways (CGR), at the same time as the 7th Class.

Three new versions of the 6th Class locomotive entered service on the CGR in 1901, two American-built and one British-built. The British version was built by Neilson, Reid and Company, who delivered 21 engines. 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 were also equipped with the 17 inches (432 millimetres) diameter cylinders which had been used on all previous 6th Class locomotives with the exception of the Class 6G. Another similarity to the early 6th Class locomotives was their lower running boards with fairings or splashers over the coupled wheels.

Upon delivery, nine of them were numbered in the range from 278 to 286 and allocated to the Western System of the CGR. The other twelve were numbered in the range from 601 to 612 for the Midland System, but later renumbered in the range from 541 to 552.

One of these locomotives, the Western System's no. 286, was an experimental locomotive, 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 heating surface area of the water, albeit at the cost of increased boiler complexity. On CGR no. 286, as built, visible exterior evidence of the presence of Drummond tubes was rectangular covers attached to the sides of the firebox just ahead of the cab.