South African Class GE 2-8-2+2-8-2

South African Class GE 2-8-2+2-8-2
First batch Class GE no. 2264, c. 1924
Type and origin ♠ Engine numbers 2260-2275 ♥ Engine numbers 2276 & 2277 ♣ Engine numbers 2260-2265 ♦ Engine numbers 2266-2275 Power type Steam Designer Beyer, Peacock and Company Builder Beyer, Peacock and Company Serial number 6193-6198, 6339-6348, 6716-6717 Model Class GE Build date 1924-1930 Total produced 18
Specifications Configuration: ​  • Whyte 2-8-2+2-8-2 (Double Mikado)  • UIC 1'D1'+1'D1'h4 Driver 3rd & 5th coupled axles Gauge 3 ft 6 in (1,067 mm) Cape gauge Leading dia. 28 1⁄2 in (724 mm) Coupled dia. 45 1⁄2 in (1,156 mm) as built 46 in (1,168 mm) retyred Trailing dia. 28 1⁄2 in (724 mm) Wheelbase 70 ft (21,336 mm)  • Engine ♠ 22 ft 10 1⁄2 in (6,972 mm) each ♥ 22 ft 11 in (6,985 mm) each  • Coupled 12 ft 9 in (3,886 mm) each Pivot centres 35 ft (10,668 mm) Length: ​  • Over couplers ♠ 76 ft 8 3⁄4 in (23,387 mm) ♥ 76 ft 8 1⁄4 in (23,374 mm) Height 12 ft 11 11⁄16 in (3,954 mm) Frame type Plate Axle load ♠ 13 LT 9 cwt (13,670 kg) ♥ 13 LT 3 cwt (13,360 kg)  • Leading ♠ 11 LT 4 cwt (11,380 kg) front 11 LT (11,180 kg) rear ♥ 11 LT 2 cwt (11,280 kg) front 11 LT 10 cwt (11,680 kg) rear  • 1st coupled ♠ 12 LT 6 cwt (12,500 kg) ♥ 12 LT 3 cwt (12,340 kg)  • 2nd coupled ♠ 13 LT 1 cwt (13,260 kg) ♥ 13 LT 3 cwt (13,360 kg)  • 3rd coupled ♠ 12 LT 19 cwt (13,160 kg) ♥ 13 LT 1 cwt (13,260 kg)  • 4th coupled ♠ 12 LT 19 cwt (13,160 kg) ♥ 13 LT 1 cwt (13,260 kg)  • 5th coupled ♠ 13 LT 7 cwt (13,560 kg) ♥ 12 LT 18 cwt (13,110 kg)  • 6th coupled ♠ 13 LT 7 cwt (13,560 kg) ♥ 12 LT 18 cwt (13,110 kg)  • 7th coupled ♠ 13 LT 9 cwt (13,670 kg) ♥ 13 LT (13,210 kg)  • 8th coupled ♠ 12 LT 2 cwt (12,290 kg) ♥ 12 LT 11 cwt (12,750 kg)  • Trailing ♠ 11 LT 3 cwt (11,330 kg) front 11 LT 11 cwt (11,740 kg) rear ♥ 11 LT 7 cwt (11,530 kg) front 11 LT 4 cwt (11,380 kg) rear Adhesive weight ♠ 103 LT 10 cwt (105,200 kg) ♥ 102 LT 15 cwt (104,400 kg) Loco weight ♠ 148 LT 8 cwt (150,800 kg) ♥ 147 LT 18 cwt (150,300 kg) Fuel type Coal Fuel capacity 9 LT (9.1 t) Water cap 3,300 imp gal (15,000 l) front 1,300 imp gal (5,910 l) rear Firebox type Belpaire  • Firegrate area 52 sq ft (4.8 m2) Boiler: ​  • Pitch 7 ft 9 1⁄4 in (2,369 mm)  • Diameter 6 ft 9 in (2,057 mm)  • Tube plates 11 ft 3 in (3,429 mm)  • Small tubes 288: 2 in (51 mm)  • Large tubes 36: 5 1⁄2 in (140 mm) Boiler pressure 180 psi (1,241 kPa) Safety valve Ramsbottom Heating surface ♣ 2,589 sq ft (240.5 m2) ♦ 2,576 sq ft (239.3 m2) ♥ 2,603 sq ft (241.8 m2)  • Tubes 2,374 sq ft (220.552 m2)  • Arch tubes ♥ 27 sq ft (2.5 m2)  • Firebox ♣ 215 sq ft (20.0 m2) ♦♥ 202 sq ft (18.8 m2) Superheater: ​  • Heating area ♣ 362 sq ft (33.6 m2) ♦ 349 sq ft (32.4 m2) ♥ 364 sq ft (33.8 m2) Cylinders Four Cylinder size ♠ 18 in (457 mm) bore ♥ 19 in (483 mm) bore ♠♥ 24 in (610 mm) stroke Valve gear Walschaerts Valve type Piston Couplers Johnston link-and-pin AAR knuckle (1930s)
Performance figures Tractive effort ♠ 45,640 lbf (203.0 kN) @ 75% ♥ 50,850 lbf (226.2 kN) @ 75%
Career Operators South African Railways Class Class GE Number in class 18 Numbers 2260-2277 Delivered 1925-1931 First run 1925 Withdrawn 1975

The South African Railways Class GE 2-8-2+2-8-2 of 1925 was an articulated steam locomotive.

Between 1925 and 1931, the South African Railways placed eighteen Class GE Garratt articulated locomotives with a 2-8-2+2-8-2 Double Mikado type wheel arrangement in service. They were built in three batches over six years.

In 1924, specifications were prepared by Colonel F.R. Collins DSO, Chief Mechanical Engineer of the South African Railways (SAR), for the Class GE 2-8-2+2-8-2 Double Mikado type Garratt locomotive. An order was placed with Beyer, Peacock and Company (BP) for the design and construction of six locomotives. They were delivered during March 1925, numbered in the range from 2260 to 2265 and erected in the Salvokop workshops in Pretoria. The Class GE was the only purebred Garratt Double Mikado type to see service on the SAR.

The locomotives proved to be most successful and a second order for ten engines was placed with BP in 1926. These were placed in traffic during November of that year, numbered in the range from 2266 to 2275.

A third order for two locomotives, also from BP, followed in 1930, numbered 2276 and 2277 and placed in service in February 1931.

The Class GE Garratt was designed as a heavy goods locomotive for use on light 60 pounds per yard (30 kilograms per metre) rail. It was an enlarged version of the Class GD 2-6-2+2-6-2 Double Prairie type. The Class GD were the first eight-coupled Garratts to be built for the SAR and at the time of their introduction, they were the most powerful locomotives in respect of tractive effort operating on light track in Africa and the Southern Hemisphere.

They had plate frames, steel Belpaire fireboxes and were superheated, with four safety valves set at 180 pounds per square inch (1,241 kilopascals). Their piston valves were actuated by Walschaerts valve gear, controlled by steam reversing gear. As delivered, they had 45 ¹⁄₂ inches (1,156 millimetres) diameter coupled wheels which were later retyred to 46 inches (1,168 millimetres) diameter. The two water tanks had a combined capacity of 4,600 imperial gallons (20,900 litres). They had a water-filling tube hole on the front tank only since the front and rear tanks were connected by leveling pipes in accordance with the usual Garratt practice. The locomotives were delivered with mechanical lubricators, but these were later removed.