South African Class 6A 4-6-0

CGR 6th Class 4-6-0 1896 South African Class 6A 4-6-0
SAR no. 444 with a Belpaire firebox, near Clovelly, c. 1930
Type and origin ♠ Original locomotive, as built ♥ Locomotive equipped with Belpaire firebox Power type Steam Designer Cape Government Railways (H.M. Beatty) Builder Dübs and Company Sharp, Stewart and Company Serial number Dübs: 3330, 3332-3335, 3337, 3345-3347, 3437-3439, 3441-3447, 3449-3456, 3460-3466, 3469-3471, 3475-3476 Sharp Stewart: 4116-4119, 4122-4127, 4144 Model CGR 6th Class Build date 1895-1897 Total produced 50
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 5⁄8 in (12,817 mm)  • Engine 20 ft 3 3⁄4 in (6,191 mm)  • Leading 5 ft 5 1⁄2 in (1,664 mm)  • Coupled 11 ft (3,353 mm)  • Tender 10 ft (3,048 mm) Wheel spacing (Asymmetrical) 1-2: 4 ft 9 in (1,448 mm) 2-3: 6 ft 3 in (1,905 mm) Length: ​  • Over couplers 51 ft 3 5⁄8 in (15,637 mm) Height ♠ 12 ft 10 in (3,912 mm) ♥ 12 ft 10 3⁄8 in (3,921 mm) Frame type Plate Axle load ♠ 11 LT 18 cwt (12,090 kg) ♥ 13 LT 8 cwt (13,620 kg)  • Leading ♠ 11 LT 7 cwt (11,530 kg) ♥ 10 LT 17 cwt 2 qtr (11,050 kg)  • Coupled ♥ 13 LT 8 cwt (13,620 kg)  • 1st coupled ♠ 11 LT 5 cwt (11,430 kg)  • 2nd coupled ♠ 11 LT 18 cwt (12,090 kg)  • 3rd coupled ♠ 11 LT 5 cwt (11,430 kg)  • Tender axle 10 LT 8 cwt (10,570 kg) average Adhesive weight ♠ 34 LT 8 cwt (34,950 kg) ♥ 40 LT 4 cwt (40,850 kg) Loco weight ♠ 45 LT 15 cwt (46,480 kg) ♥ 51 LT 1 cwt 2 qtr (51,890 kg) Tender weight 31 LT 4 cwt (31,700 kg) Total weight ♠ 76 LT 19 cwt (78,180 kg) ♥ 82 LT 5 cwt 2 qtr (83,600 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 - ♥ Belpaire  • Firegrate area ♠ 16.625 sq ft (1.5445 m2) ♥ 16.6 sq ft (1.54 m2) Boiler: ​  • Pitch ♠ 6 ft 8 in (2,032 mm) ♥ 7 ft (2,134 mm)  • Diameter ♠ 4 ft 4 in (1,321 mm) ♥ 4 ft 9 in (1,448 mm)  • Tube plates ♠ 11 ft 2 1⁄8 in (3,407 mm) ♥ 11 ft 2 1⁄8 in (3,407 mm)  • Small tubes ♠ 185: 1 7⁄8 in (48 mm) ♥ 220: 2 in (51 mm) Boiler pressure ♠ 160 psi (1,103 kPa) ♥ 180 psi (1,241 kPa) Safety valve Ramsbottom Heating surface ♠ 1,116 sq ft (103.7 m2) ♥ 1,398.5 sq ft (129.92 m2)  • Tubes ♠ 1,015 sq ft (94.3 m2) ♥ 1,287.5 sq ft (119.61 m2)  • Firebox ♠ 101 sq ft (9.4 m2) ♥ 111 sq ft (10.3 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 Imperial Military Railways Benguela Railway South African Railways Sudan Railways Class CGR 6th Class, SAR Class 6A Number in class 50 CGR, 49 SAR Numbers CGR 161-201, 371-376, 660-662 (371-376 renumbered 571-576) IMR C501, C503, C509 & C510 Benguela 21 SAR 441-489 Delivered 1896-1897 First run 1896 Withdrawn 1973

The South African Railways Class 6A 4-6-0 of 1896 was a steam locomotive from the pre-Union era in the Cape of Good Hope.

In 1896 and 1897, the Cape Government Railways placed a second batch of fifty 6th Class 4-6-0 steam locomotives in service, forty-one on its Western System, six on its Midland System and three on its Eastern System. During the Second Boer War, four of them were transferred to the Imperial Military Railways on loan, and in 1907 one was sold to the Benguela Railway in Angola. In 1912, when the remaining forty-nine locomotives were assimilated into the South African Railways, they were renumbered and designated Class 6A.

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

Between 1895 and 1897, the fifty locomotives in this second batch of the 6th Class were built by Dübs and Company and Sharp, Stewart and Company. They were delivered in 1896 and 1897, numbered in the ranges from 161 to 201 for the CGR's Western System, 371 to 376 for the Midland System and 660 to 662 for the Eastern System.

These locomotives differed from those of the previous order by having slightly larger boilers with an increased heating surface. They were the first to be delivered with Type YC tenders, which had the same coal capacity as the earlier Type YB tender of 1893, but with a water capacity of 2,590 imperial gallons (11,770 litres), compared to the 2,370 imperial gallons (10,800 litres) of the Type YB.

When the Union of South Africa was established on 31 May 1910, the three Colonial government railways (CGR, Natal Government Railways (NGR) and Central South African Railways (CSAR)) 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.