South African Class GCA 2-6-2+2-6-2

No. 2615 at Greyville, November 1971

Type and origin
♠ First order - ♥ Second order
Power type	Steam
Designer	South African Railways (Col F.R. Collins DSO)
Builder	Friedrich Krupp AG
Serial number	970-982, 1042-1068
Model	Class GCA
Build date	1927-1928
Total produced	39

Specifications
Configuration:
• Whyte	2-6-2+2-6-2 (Double Prairie)
• UIC	1'C1'+1'C1'h4t
Driver	3rd & 4th coupled axles
Gauge	3 ft 6 in (1,067 mm) Cape gauge
Leading dia.	28+1⁄2 in (724 mm)
Coupled dia.	42+3⁄4 in (1,086 mm)
Trailing dia.	28+1⁄2 in (724 mm)
Wheelbase	56 ft 8 in (17,272 mm)
• Engine	17 ft 8+1⁄4 in (5,391 mm) each
• Coupled	8 ft (2,438 mm) each
Pivot centres	29 ft 8 in (9,042 mm)
Length:
• Over couplers	64 ft 9 in (19,736 mm)
Height	12 ft 7 in (3,835 mm)
Frame type	Bar
Axle load	♠ 11 LT 16 cwt (11,990 kg) ♥ 11 LT 14 cwt (11,890 kg)
• Leading	♠ 10 LT 2 cwt (10,260 kg) front 10 LT 17 cwt (11,020 kg) rear ♥ 10 LT 10 cwt (10,670 kg) front 10 LT 9 cwt (10,620 kg) rear
• 1st coupled	♠ 10 LT 19 cwt (11,130 kg) ♥ 10 LT 16 cwt (10,970 kg)
• 2nd coupled	♠ 10 LT 12 cwt (10,770 kg) ♥ 10 LT 19 cwt (11,130 kg)
• 3rd coupled	♠ 10 LT 12 cwt (10,770 kg) ♥ 10 LT 19 cwt (11,130 kg)
• 4th coupled	♠ 11 LT 2 cwt (11,280 kg) ♥ 11 LT 13 cwt (11,840 kg)
• 5th coupled	♠ 11 LT 2 cwt (11,280 kg) ♥ 11 LT 14 cwt (11,890 kg)
• 6th coupled	♠ 11 LT 16 cwt (11,990 kg) ♥ 10 LT 16 cwt (10,970 kg)
• Trailing	♠ 8 LT 8 cwt (8,535 kg) front 8 LT 16 cwt (8,941 kg) rear ♥ 8 LT 14 cwt (8,840 kg) front 9 LT 6 cwt (9,449 kg) rear
Adhesive weight	♠ 66 LT 3 cwt (67,210 kg) ♥ 66 LT 17 cwt (67,920 kg)
Loco weight	♠ 104 LT 6 cwt (106,000 kg) ♥ 105 LT 16 cwt (107,500 kg)
Fuel type	Coal
Fuel capacity	7 LT (7.1 t)
Water cap.	2,000 imp gal (9,090 L) front 1,000 imp gal (4,550 L) rear
Firebox:
• Type	Round top
• Grate area	34 sq ft (3.2 m²)
Boiler:
• Pitch	7 ft 4+3⁄8 in (2,245 mm)
• Diameter	5 ft 2 in (1,575 mm)
• Tube plates	11 ft 3+5⁄8 in (3,445 mm)
• Small tubes	141: 2 in (51 mm)
• Large tubes	24: 5+1⁄2 in (140 mm)
Boiler pressure	180 psi (1,241 kPa)
Safety valve	Pop
Heating surface	1,388 sq ft (128.9 m²)
• Tubes	1,225 sq ft (113.8 m²)
• Arch tubes	21 sq ft (2.0 m²)
• Firebox	142 sq ft (13.2 m²)
Superheater:
• Heating area	331 sq ft (30.8 m²)
Cylinders	Four
Cylinder size	14 in (356 mm) bore 23 in (584 mm) stroke
Valve gear	Heusinger
Valve type	Piston
Couplers	AAR knuckle

Performance figures
Tractive effort	28,470 lbf (126.6 kN) @ 75%

Career
Operators	South African Railways
Class	Class GCA
Number in class	39
Numbers	2190-2202, 2600-2625
Delivered	1927-1928
First run	1927
Withdrawn	1975

The South African Railways Class GCA 2-6-2+2-6-2 of 1927 was an articulated steam locomotive.

In 1927, the South African Railways placed thirteen Class GCA Garratt articulated steam locomotives with a 2-6-2+2-6-2 Double Prairie type wheel arrangement in branch line service. Another batch of twenty-six locomotives was acquired in 1928.^[1]^[2]^[3]

Manufacturer

The Class GCA 2-6-2+2-6-2 Double Prairie type Garratt steam locomotive was built to the specifications and design of Colonel F.R. Collins DSO, Chief Mechanical Engineer of the South African Railways (SAR), based on the design of the Class GC Garratt. Thirteen locomotives were ordered from Friedrich Krupp AG of Essen in Germany, who delivered them during October 1927, numbered in the range from 2190 to 2202.^[1]^[2]^[3]^[4]^[5]^[6]^[7]

A second order for another 26 locomotives was placed with the same manufacturer in 1928. These were numbered in the range from 2600 to 2625 when they were delivered during August in that same year.^[1]^[3]^[4]^[5]

Characteristics

The Class GCA had the same tractive effort and main dimensions as the Class GC, but was built on bar frames instead of plate frames. They also differed in general appearance by having round-topped fireboxes, compared to the Belpaire fireboxes of the Class GC, and with water tanks and built-up coal bunkers of a different shape. The second batch of locomotives differed slightly from the first and were 1 long ton 10 hundredweight (1,524 kilograms) heavier. Like the predecessor Class GC, they were all superheated and had Walschaerts valve gear.^[1]^[3]

The Class GCA proved to be good locomotives, although some trouble was experienced with coupling rods breaking, much of which was attributed to running them at excessive speed to maintain schedules with their small coupled wheel diameter of only 42+3⁄4 inches (1,086 millimetres).^[1]^[2]^[3]

Experience showed that the performance of these locomotives could have been better if they had been fitted with somewhat larger cylinders since their boilers still had an appreciable margin of capacity.^[2]

Service

The first batch of locomotives were placed in service on the Natal South Coast line and shedded at Greyville, while the second batch were distributed wherever their services were required. These could be found working around Pietermaritzburg on the Donnybrook to Underberg and Greytown to Mount Alida branch lines, while some ended up at Nelspruit in the Eastern Transvaal Lowveld for service on the Graskop branch line. They were even tested on the South West Africa System.^[1]^[2]^[3]^[8]

By October 1971, after more than four decades of service, all Greyville's Class GCAs had been withdrawn since they were no longer needed after completion of the South Coast line’s electrification. By 1973, the thirty-nine original members of the Class had dwindled to seven, all stationed at Mason's Mill in Pietermaritzburg, from where they still worked the light rail Underberg branch, often double-heading. By April of that year, however, the number had dropped to five. They were all withdrawn from service in October 1975. One of their last tasks was to work the track re-railing train which laid the heavier rails which enabled diesel-electric locomotives to finally replace them.^[7]^[9]

Knuckle couplers

In 1927, the SAR began to convert the couplers of its Cape Gauge rolling stock from the Johnston link-and-pin coupling system which had been in use since the establishment of the Cape Government Railways in 1873, to AAR knuckle couplers. Judging from contemporary photographs as well as the official SAR Locomotive Diagram Book and the dimensional locomotive drawings as published by Holland, which were for the most part based on the original as-delivered and unmodified locomotives, the Class GCA locomotives were delivered new with knuckle couplers fitted, as were the Classes 18, GF, HF and U which also entered service in 1927.^[1]^[4]^[5]

Conversion of all rolling stock would take several years and both coupler types could still be seen on rolling stock into the late 1950s. During the transition period, knuckle couplers on locomotives had a horizontal gap and a vertical hole in the knuckle itself to accommodate a link and a pin respectively. This enabled them to couple to vehicles which were still equipped with the older Johnston couplers.^[1]^[4]^[5]

Knuckle couplers had first been used in South Africa more than two decades earlier. The Central South African Railways (CSAR) introduced Gould knuckle couplers on the rolling stock of its Limited Express and Imperial Mail passenger trains in 1904. The Limited Express operated between Pretoria and Johannesburg while the Imperial Mail operated between Pretoria and Cape Town. These knuckle-couplers also had split knuckles to accommodate coupling to the old Johnston couplers with a link and pin, since the CSAR retained the old couplers on all their locomotives to keep them compatible with their own goods and older passenger rolling stock as well as with that from the other railways it connected with.^[10]

Preservation

Number	THF / Private	Leaselend / Owner	Current Location
2196	THF		White River Station
2199	THF		Krugersdorp Locomotive Depot
2621	THF	Ingwe Municipality	Creighton Station

Illustration

No. 2621, plinthed at Nelspruit, April 1991. Later this locomotive was removed from the plinth and stored at Waterval - Boven. In 2016, it was moved to Creighton to be restored to operating condition by the Paton's Country Railway.

References

Wikimedia Commons has media related to South African Class GCA 2-6-2+2-6-2.

^ ^a ^b ^c ^d ^e ^f ^g ^h Holland, D. F. (1972). Steam Locomotives of the South African Railways. Vol. 2: 1910-1955 (1st ed.). Newton Abbott, England: David & Charles. pp. 52–54. ISBN 978-0-7153-5427-8.
^ ^a ^b ^c ^d ^e Espitalier, T.J.; Day, W.A.J. (1946). The Locomotive in South Africa - A Brief History of Railway Development. Chapter VII - South African Railways (Continued). South African Railways and Harbours Magazine, January 1946. pp. 12-13.
^ ^a ^b ^c ^d ^e ^f Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. p. 90. ISBN 0869772112.
^ ^a ^b ^c ^d South African Railways & Harbours/Suid Afrikaanse Spoorweë en Hawens (15 Aug 1941). Locomotive Diagram Book/Lokomotiefdiagramboek, 3'6" Gauge/Spoorwydte. SAR/SAS Mechanical Department/Werktuigkundige Dept. Drawing Office/Tekenkantoor, Pretoria. p. 30.
^ ^a ^b ^c ^d South African Railways & Harbours/Suid Afrikaanse Spoorweë en Hawens (15 Aug 1941). Locomotive Diagram Book/Lokomotiefdiagramboek, 2'0" & 3'6" Gauge/Spoorwydte, Steam Locomotives/Stoomlokomotiewe. SAR/SAS Mechanical Department/Werktuigkundige Dept. Drawing Office/Tekenkantoor, Pretoria. p. 30.
^ Hamilton, Gavin N., The Garratt Locomotive - Garratt Locomotives from Other Builders, retrieved 10 November 2012
^ ^a ^b Durrant, AE (1989). Twilight of South African Steam (1st ed.). Newton Abbott: David & Charles. p. 110. ISBN 0715386387.
^ Soul of A Railway, System 6, Part 2: Greyville Loco, Greyville Station to Umgeni & Berea Road to Rossburgh. Caption 22. (Accessed on 26 November 2016)
^ Soul of A Railway, System 6, Part 1: Durban Old Station. Caption 69. Archived 24 October 2020 at the Wayback Machine (Accessed on 8 March 2017)
^ Soul of A Railway, System 8, Part 1: Pretoria: including local services, workshops and running sheds, Part 1. Captions 8, 13. Archived 19 March 2017 at the Wayback Machine (Accessed on 15 March 2017)

Locomotives of South Africa

Steam

7' ¼" gauge	East London 0-4-0VB Table Bay 0-4-0ST Table Bay 0-4-0T Table Bay 0-4-0WT
Standard gauge	Cape 0-4-0T Blackie Cape 0-4-2 Cape 2-4-0T CGR 0-4-0ST Aid Natal 0-4-0ST Durban Natal 0-4-0WT Natal Natal 4-4-0T Perseverance
Cape gauge Tank engines	CGR 0-4-0ST 1873 CGR 0-4-0ST 1874 CGR 0-4-0ST 1881 CGR 0-4-0ST 1881 Coffee Pot CGR 0-6-0ST CGR 0-6-0T CGR 2-6-0ST 1900 CGR 2-6-0ST 1902 CGR 1st Class 0-4-0ST 1875 CGR 1st Class 0-4-0ST 1876 CGR 1st Class 2-6-0ST CGR 1st Class 4-4-0T CGR 2nd Class 4-4-0T CGR 3rd Class 2-6-0T CGR Railmotor CSAR Class C CSAR Class E CSAR Rack 4-6-4RT CSAR Railmotor Durban's Congella Durban's Edward Innes Durban's John Milne Durban's Sir Albert Port Elizabeth 0-4-0ST Kowie Railway 0-6-0T Kowie Railway 4-4-0T Metropolitan & Suburban 4-6-2T NGR 2-6-0T Durban & Pietermaritzburg NGR Class I 2-6-2T NGR Class K 0-4-0ST NGR Class K 0-6-0ST NGR Class K 2-6-0T NZASM 10 Tonner NZASM 13 Tonner NZASM 14 Tonner NZASM 18 Tonner NZASM 19 Tonner NZASM 32 Tonner NZASM 40 Tonner PPR 26 Tonner PPR 35 Tonner Portuguese SAR Class A SAR Class B SAR Class C SAR Class C1 SAR Class C2 SAR Class D SAR Class E SAR Class F SAR Class G SAR Class H SAR Class H1 SAR Class H2 SAR Class J SAR Class K SAR Railmotor SAR Dock 0-4-0ST SAR Dock 0-4-0T SWA 2-8-0T
Cape gauge Tender engines	CGR 1st Class 2-6-0 1876 BP CGR 1st Class 2-6-0 1876 Kitson CGR 1st Class 2-6-0 1879 CGR 1st Class 2-6-0 1891 CGR 1st Class 4-4-0 CGR 1st Class 4-4-0TT CGR 2nd Class 2-6-2TT CGR 3rd Class 4-4-0 1883 CGR 3rd Class 4-4-0 1884 CGR 3rd Class 4-4-0 1889 CGR 3rd Class 4-4-0 1898 CGR 3rd Class 4-4-0 1901 CGR 3rd Class 4-4-0 1903 CGR 4th Class 4-4-2 CGR 4th Class 4-6-0TT 1880 CGR 4th Class 4-6-0TT 1882 CGR 4th Class 4-6-0TT 1882 Joy CGR 4th Class 4-6-0TT 1884 CGR 5th Class 4-6-0 1890 CGR 5th Class 4-6-0 1891 NGR Havelock NGR Class I SAR Class Exp 1 SAR Class Exp 2 SAR Class Exp 3 SAR Class Exp 4 SAR Class Exp 5 SAR Class Exp 6 SAR Class S SAR Class S1 SAR Class S2 SAR Class 1 SAR Class 1A SAR Class 1B SAR Class 2 SAR Class 2C SAR Class 3 SAR Class 3A SAR Class 3B SAR Class 4 SAR Class 4A SAR Class 5 SAR Class 5A SAR Class 5B SAR Class 6 SAR Class 6A SAR Class 6B SAR Class 6C SAR Class 6D SAR Class 6E SAR Class 6F SAR Class 6G SAR Class 6H SAR Class 6J SAR Class 6K SAR Class 6L SAR Class 6Y SAR Class 6Z SAR Class 7 SAR Class 7A SAR Class 7B SAR Class 7C SAR Class 7D SAR Class 7E SAR Class 7F SAR Class 8 SAR Class 8A SAR Class 8B SAR Class 8C SAR Class 8D SAR Class 8E SAR Class 8F SAR Class 8R SAR Class 8X SAR Class 8Y SAR Class 8Z SAR Class 9 SAR Class 10 SAR Class 10A SAR Class 10B SAR Class 10C SAR Class 10D SAR Class 11 SAR Class 12 SAR Class 12A SAR Class 12B SAR Class 13 SAR Class 14 SAR Class 14A SAR Class 14B SAR Class 14C 1st SAR Class 14C 2nd SAR Class 14C 3rd SAR Class 14C 4th SAR Class 15 SAR Class 15A SAR Class 15B SAR Class 15C SAR Class 15CA SAR Class 15E SAR Class 15F SAR Class 16 SAR Class 16A SAR Class 16B SAR Class 16C SAR Class 16D SAR Class 16DA 1928 SAR Class 16DA 1930 SAR Class 16E SAR Class 17 SAR Class 18 SAR Class 19 SAR Class 19A SAR Class 19B SAR Class 19C SAR Class 19D SAR Class 20 SAR Class 21 SAR Class 23 SAR Class 24 SAR Class 25 SAR Class 25NC SAR Class 26 SAR Katanga SWA 2-8-0
Cape gauge Articulated engines	CGR Fairlie CGR Kitson-Meyer SAR Class FC SAR Class FD SAR Class GA SAR Class GB SAR Class GC SAR Class GCA SAR Class GD SAR Class GDA SAR Class GE SAR Class GEA SAR Class GF SAR Class GG SAR Class GH SAR Class GK SAR Class GL SAR Class GM SAR Class GMA SAR Class GO SAR Class HF SAR Class KM SAR Class MA SAR Class MB SAR Class MC SAR Class MC1 SAR Class MD SAR Class ME SAR Class MF SAR Class MG SAR Class MH SAR Class MJ SAR Class MJ1 SAR Class U
2' 6" gauge	Cape Copper John King & Miner Cape Copper Britannia Cape Copper Caledonia Cape Copper Clara Cape Copper Condenser Cape Copper Scotia Namaqua Copper Pioneer Walvis Bay 2-4-2T Hope
2' & 600mm gauges	ACR Class NG-G16A CGR NG 0-4-0T CGR NG 0-6-0T CGR NG 4-6-2T CGR Type A 2-6-4T CGR Type C 0-4-0T NGR Class N 4-6-2T SAR Dutton SAR NG 0-4-0T SAR Class NG1 SAR Class NG2 SAR Class NG3 SAR Class NG4 SAR Class NG5 SAR Class NG6 SAR Class NG7 SAR Class NG8 SAR Class NG9 SAR Class NG10 SAR Class NG-G11 SAR Class NG-G12 SAR Class NG-G13 SAR Class NG-G14 SAR Class NG15 SAR Class NG-G16 SWA Class Ha SWA Class Hb SWA Class Hc SWA Class Hd SWA Jung SWA Zwillinge

Electric

Amcoal Class E38

Gas-electric

SAR Gas-electric

Diesel

Cape gauge Diesel-electric	PRASA Class Afro 4000 SAR Class DS SAR Class DS1 SAR Class 31-000 SAR Class 32-000 SAR Class 32-200 SAR Class 33-000 SAR Class 33-200 SAR Class 33-400 SAR Class 34-000 SAR Class 34-200 SAR Class 34-400 SAR Class 34-500 SAR Class 34-600 SAR Class 34-800 SAR Class 34-900 SAR Class 35-000 SAR Class 35-200 SAR Class 35-400 SAR Class 35-600 TFR Class 35-800 SAR Class 36-000 SAR Class 36-200 SAR Class 37-000 Spoornet Class 39-000 TFR Class 39-200 TFR Class 43-000 TFR Class 44-000 TFR Class 45-000
2' gauge Diesel-electric	SAR Class 91-000
Cape gauge Diesel-hydraulic	SAR Class 61-000
Cape gauge Electro-diesel	Spoornet Class 38-000

This page was last edited on 13 August 2023, at 23:47