South African Class MJ 2-6-6-0

28+1⁄2 in (724 mm)Coupled dia.42+3⁄4 in (1,086 mm)Tender wheels34 in (864 mm)Wheelbase58 ft 11+1⁄4 in (17,964 mm) ​ • Engine32 ft 8 in (9,957 mm) • Coupled8 ft 4 in (2,540 mm) per unit • Tender16 ft 9 in (5,105 mm) • Tender bogie4 ft 7 in (1,397 mm)Length:
​ • Over couplers67 ft 5+1⁄8 in (20,552 mm)Height♠♥ 12 ft 6+1⁄8 in (3,813 mm)Frame typeBarAxle load♠ 13 LT 15 cwt (13,970 kg) ​ • Leading♠ 7 LT 17 cwt (7,976 kg) • 1st coupled♠ 12 LT 12 cwt (12,800 kg) • 2nd coupled♠ 12 LT 13 cwt (12,850 kg) • 3rd coupled♠ 12 LT 19 cwt (13,160 kg) • 4th coupled♠ 11 LT 8 cwt (11,580 kg) • 5th coupled♠ 12 LT 16 cwt (13,010 kg) • 6th coupled♠ 13 LT 15 cwt (13,970 kg) • Tender bogieBogie 1: 27 LT 10 cwt (27,940 kg)
Bogie 2: 23 LT 11 cwt (23,930 kg) • Tender axle13 LT 15 cwt (13,970 kg)Adhesive weight♠ 76 LT 3 cwt (77,370 kg)Loco weight♠ 84 LT (85,350 kg)Tender weight51 LT 1 cwt (51,870 kg)Total weight♠ 135 LT 1 cwt (137,200 kg)Tender typeMP1 (2-axle bogies)
MP, MP1, MR permittedFuel typeCoalFuel capacity10 LT (10.2 t)Water cap.4,250 imp gal (19,300 L)Firebox:​ • Type♠♥ Belpaire • Grate area♠♥ 40 sq ft (3.7 m²)Boiler:
​ • Pitch♠♥ 7 ft 9+1⁄8 in (2,365 mm) • Diameter♠♥ 5 ft 1+1⁄2 in (1,562 mm) • Tube plates♠ 17 ft (5,182 mm)
♥ 17 ft 1⁄4 in (5,188 mm) • Small tubes♠♥ 151: 2 in (51 mm) • Large tubes♠♥ 18 5+1⁄2 in (140 mm)Boiler pressure♠♥ 200 psi (1,379 kPa)Safety valveRamsbottomHeating surface:​ • Firebox♠ 130 sq ft (12 m²)
♥ 133 sq ft (12.4 m²) • Tubes♠ 1,783 sq ft (165.6 m²)
♥ 1,780 sq ft (165 m²) • Total surface♠♥ 1,913 sq ft (177.7 m²)Superheater:
​ • TypeSchmidt • Heating area♠ 343 sq ft (31.9 m²)
♥ 350 sq ft (33 m²)CylindersFourHigh-pressure cylinder16+1⁄2 in (419 mm) bore
24 in (610 mm) strokeLow-pressure cylinder26 in (660 mm) bore
24 in (610 mm) strokeValve gearWalschaertsValve typePistonCouplersJohnston link-and-pin
AAR knuckle (1930s)

Performance figures
Tractive effort	♠ 38,170 lbf (169.8 kN) @ 50% ♥ 37,950 lbf (168.8 kN) @ 50%

Career
Operators	South African Railways
Class	Class MJ
Number in class	18
Numbers	1651-1660, 1674-1681
Delivered	1914-1921
First run	1914
Scrapped	1962

The South African Railways Class MJ 2-6-6-0 of 1914 was a class of articulated steam locomotives.

Between 1914 and 1921, the South African Railways placed eighteen Class MJ Mallet articulated compound steam locomotives with a 2-6-6-0 wheel arrangement in branch line service.^[1][2][3][4]

The Class MJ 2-6-6-0 Mallet articulated compound steam locomotive was designed by D.A. Hendrie, Chief Mechanical Engineer (CME) of the South African Railways (SAR) from 1910 to 1922, to meet the need for engines with a higher tractive effort to cope with heavy traffic on branch lines.^[1][2][4]

Ten of these branch line locomotives were ordered from Maffei of Munich but, as a result of the outbreak of the First World War, only two could be delivered from Germany in 1914, numbered 1651 and 1652.^[1][2][4]

The order for the remaining eight was then transferred to the North British Locomotive Company (NBL) in Scotland, who delivered them in 1917 and 1918, numbered in the range from 1653 to 1660. The entry for the Mallets in the NBL works register shows them as ordered on 20 April 1915 and delivered from February to March 2016. Those dates are probably ex works dates rather than actual delivery dates.^{[1][2][4][5][6]}

After cessation of hostilities in 1918, Maffei approached the SAR and requested that the balance of the original order, which had been built in 1914 but could not be delivered because of the war, also be accepted. These eight locomotives were delivered in 1921, numbered in the range from 1674 to 1681.^[1][2][4][7]

The locomotives had Walschaerts valve gear and were superheated, using the Schmidt type superheater. Unlike most of the other SAR Mallet classes, which had round-topped fireboxes, the Class MJ had Belpaire fireboxes. The four cylinders were arranged outside the 4 inches (102 millimetres) thick bar frames.^[1][2][4]

The locomotives were delivered with Type MP1 tenders with a coal capacity of 10 long tons (10.2 tonnes) and a water capacity of 4,250 imperial gallons (19,300 litres). The same tender was used by altogether fifteen other SAR locomotive Classes.^[2][3]

During 1939, while W.A.J. Day was the CME of the SAR, the Classes MJ and MJ1 were modified slightly to be reboilered with the same standard boiler, once again with Belpaire fireboxes.^[2]

With its light axle loading, the Class MJ was intended for branch line working. Most of them were placed in service in the Eastern Cape, but four went to Natal and are believed to have worked on the Eshowe branch line. They gave satisfactory service on the Cape Eastern System where the moderate speeds required on the sections over which they worked enabled them to give reasonably good results.^[1][2][4]

Two of the locomotives, NBL-built no. 1655 and Maffei-built no. 1674, had the distinction of being the last two Mallet engines to remain in SAR service. They were scrapped in the East London workshops in 1962, after having worked on the branch line between Amabele and Umtata in Transkei for most of their service lives and then having spent their last years in shunting service in East London.^[8]

The known works numbers for the eight NBL-built locomotives are recorded as 21248 to 21255. However, these numbers are in conflict with the NBL works numbers 21246 to 21275 which were allocated to thirty 2-8-2T locomotives, numbered 5381 to 5410 [fr] and built by NBL for the Paris-Orleans Railway in France. Preceding and following NBL works numbers that are also in conflict with those recorded for the French locomotives are:^[1][5][6]

• Works numbers 21246 and 21247 of the last two of six 45-class 0-6-2T locomotives built for the Glasgow and South Western Railway in January 1916.^[5][6]
• Works numbers 21256 to 21275 of twenty named Prince of Wales class 4-6-0 locomotives built for the London and North Western Railway between October 1915 and January 1916.^[5][6]

In the official NBL builders list, the Paris-Orleans 2-8-2Ts are shown as ordered in September 1915 and delivered from March to June 1916. Their duplicated works numbers are listed as "progressive numbers" 21246A to 21275A.^[5][6]

The builders, works numbers, years of entering service and engine numbers of the Class MJ are listed in the table.^[1]

SAR Class MJ 2-6-6-0 of 1914

Builder	Works no.	Year	SAR no.
Maffei	3452	1914	1651
Maffei	3453	1914	1652
NBL	21248	1917	1653
NBL	21249	1917	1654
NBL	21250	1917	1655
NBL	21251	1917	1656
NBL	21252	1917	1657
NBL	21253	1917	1658
NBL	21254	1917	1659
NBL	21255	1917	1660
Maffei	3454	1921	1674
Maffei	3455	1921	1675
Maffei	3456	1921	1676
Maffei	3457	1921	1677
Maffei	3458	1921	1678
Maffei	3459	1921	1679
Maffei	3460	1921	1680
Maffei	3461	1921	1681

1. ^ ^{a b c d e f g h i} Holland, D. F. (1972). Steam Locomotives of the South African Railways. Vol. 2: 1910-1955 (1st ed.). Newton Abbott, England: David & Charles. p. 29. ISBN 978-0-7153-5427-8.
2. ^ ^{a b c d e f g h i} Espitalier, T.J.; Day, W.A.J. (1945). The Locomotive in South Africa - A Brief History of Railway Development. Chapter VII - South African Railways (Continued). South African Railways and Harbours Magazine, May 1945. pp. 349-350.
3. ^ ^{a b} South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
4. ^ ^{a b c d e f g} Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 87–88. ISBN 0869772112.
5. ^ ^{a b c d e} North British Locomotive Company works list, compiled by Austrian locomotive historian Bernhard Schmeiser
6. ^ ^{a b c d e} North British Locomotive Co. (from J. Lambert)
7. ^ Hendrie (10 December 1921). "Engine Power on the S.A.R." South African Mining and Engineering Journal. XXXII (1576): 529.
8. ^ Durrant, AE (1989). Twilight of South African Steam (1st ed.). Newton Abbott: David & Charles. pp. 24–25. ISBN 0715386387.

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

ElectricGas-electricDiesel

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