South African Class 16 4-6-2
Encyclopedia
In 1914 the South African Railways placed twelve Class 16 steam locomotives with a 4-6-2
Pacific wheel arrangement in passenger train service.
in Glasgow
, Scotland
, who delivered twelve locomotives in 1914, numbered 790 to 801.
The design of the Class 16 closely followed that of the Class 15
4-8-2 Mountain type that was introduced at the same time from the same builders, and many parts were made interchangeable. They had Walschaerts valve gear, were superheated and had Belpaire firebox
es.
4-6-2 The Great Bear
on the Great Western Railway
and equalled, also at 85% boiler pressure, that of Gresley’s
later Great Northern
Pacifics. This made the Class 16 the most powerful express passenger locomotive design yet to have been built in Great Britain
at the time.
Eventually all twelve Class 16 locomotives were reboilered with Watson Standard no. 2B boilers and reclassified to Class 16R. Early conversions were equipped with copper and later conversions with steel fireboxes. In the process they were also equipped with Watson cabs, with their distinctive slanted fronts compared to the conventional vertical fronts of their original cabs.
An obvious visual difference between an original and a Watson Standard reboilered locomotive is usually a rectangular regulator cover just to the rear of the chimney on the reboilered locomotive. In the case of the Class 16 and Class 16R locomotives two even more obvious visual differences are the Watson cab and the absence of the Belpaire firebox hump between the cab and boiler on the reboilered locomotives.
and Johannesburg
and in main line service on the section from Johannesburg to Volksrust
on the line to Natal. In later years, after being withdrawn from main line passenger service, many of these locomotives were employed in suburban and shunting service.
4-6-2
4-6-2, in the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles , six powered and coupled driving wheels on three axles, and two trailing wheels on one axle .These locomotives are also known as Pacifics...
Pacific wheel arrangement in passenger train service.
Manufacturer
The Class 16 4-6-2 Pacific locomotive was designed by D.A. Hendrie, Chief Mechanical Engineer (CME) of the South African Railways (SAR) from 1910 to 1922, and was built by the North British Locomotive CompanyNorth British Locomotive Company
The North British Locomotive Company was created in 1903 through the merger of three Glasgow locomotive manufacturing companies; Sharp Stewart and Company , Neilson, Reid and Company and Dübs and Company , creating the largest locomotive manufacturing company in Europe.Its main factories were...
in Glasgow
Glasgow
Glasgow is the largest city in Scotland and third most populous in the United Kingdom. The city is situated on the River Clyde in the country's west central lowlands...
, Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
, who delivered twelve locomotives in 1914, numbered 790 to 801.
The design of the Class 16 closely followed that of the Class 15
South African Class 15 4-8-2
In 1914 the South African Railways placed ten Class 15 steam locomotives with a 4-8-2 Mountain wheel arrangement in service.-Manufacturer:The Class 15 was introduced by D.A...
4-8-2 Mountain type that was introduced at the same time from the same builders, and many parts were made interchangeable. They had Walschaerts valve gear, were superheated and had Belpaire firebox
Belpaire firebox
The Belpaire firebox is a type of firebox used on steam locomotives. It was invented by Alfred Belpaire of Belgium. It has a greater surface area at the top of the firebox, improving heat transfer and steam production...
es.
Power comparison
When built in 1914, the Class 16 was considered a very large and powerful express locomotive, even when compared to British locomotives built to run on 4 feet 8½ inches (1,435 millimetres) Standard gauge. As built with 60 inches (1,524 mm) driving wheels, the ratio of wheel diameter to rail gauge was the same as that of a Standard gauge locomotive having 81 inches (2,057.4 mm) driving wheels. Their tractive effort of 29890 pound-forces (133 kN) at 75% boiler pressure exceeded the 27800 pound-forces (123.7 kN) at 85% boiler pressure of Churchward’sGeorge Jackson Churchward
George Jackson Churchward CBE was Chief Mechanical Engineer of the Great Western Railway in the United Kingdom from 1902 to 1922.-Early career:...
4-6-2 The Great Bear
GWR 111 The Great Bear
The Great Bear, number 111, was a locomotive of the Great Western Railway. It was the first 4-6-2 Pacific locomotive used on a railway in Great Britain, and the only one of that type ever built by the GWR.- History and operation :...
on the Great Western Railway
Great Western Railway
The Great Western Railway was a British railway company that linked London with the south-west and west of England and most of Wales. It was founded in 1833, received its enabling Act of Parliament in 1835 and ran its first trains in 1838...
and equalled, also at 85% boiler pressure, that of Gresley’s
Nigel Gresley
Sir Herbert Nigel Gresley was one of Britain's most famous steam locomotive engineers, who rose to become Chief Mechanical Engineer of the London and North Eastern Railway . He was the designer of some of the most famous steam locomotives in Britain, including the LNER Class A1 and LNER Class A4...
later Great Northern
Great Northern Railway (Great Britain)
The Great Northern Railway was a British railway company established by the Great Northern Railway Act of 1846. On 1 January 1923 the company lost its identity as a constituent of the newly formed London and North Eastern Railway....
Pacifics. This made the Class 16 the most powerful express passenger locomotive design yet to have been built in Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
at the time.
Watson Standard boilers
During the 1930s many serving locomotives were reboilered with a standard boiler type designed by A.G. Watson, CME of the SAR from 1929 to 1936, as part of his standardisation policy. Such Watson Standard reboilered locomotives were reclassified by adding an "R" suffix to their classification.Eventually all twelve Class 16 locomotives were reboilered with Watson Standard no. 2B boilers and reclassified to Class 16R. Early conversions were equipped with copper and later conversions with steel fireboxes. In the process they were also equipped with Watson cabs, with their distinctive slanted fronts compared to the conventional vertical fronts of their original cabs.
An obvious visual difference between an original and a Watson Standard reboilered locomotive is usually a rectangular regulator cover just to the rear of the chimney on the reboilered locomotive. In the case of the Class 16 and Class 16R locomotives two even more obvious visual differences are the Watson cab and the absence of the Belpaire firebox hump between the cab and boiler on the reboilered locomotives.
Service
Intended for fast passenger trains in the Transvaal, Orange Free State and the upper sections of Natal where the gradients were not as severe, the Class 16 Pacifics were placed in suburban passenger service working between PretoriaPretoria
Pretoria is a city located in the northern part of Gauteng Province, South Africa. It is one of the country's three capital cities, serving as the executive and de facto national capital; the others are Cape Town, the legislative capital, and Bloemfontein, the judicial capital.Pretoria is...
and Johannesburg
Johannesburg
Johannesburg also known as Jozi, Jo'burg or Egoli, is the largest city in South Africa, by population. Johannesburg is the provincial capital of Gauteng, the wealthiest province in South Africa, having the largest economy of any metropolitan region in Sub-Saharan Africa...
and in main line service on the section from Johannesburg to Volksrust
Volksrust
Volksrust is a town in the Mpumalanga province of South Africa on the KwaZulu-Natal provincial border. The town has important beef, dairy, maize, sorghum, wool and sunflower seed industries. It was established near to where the Battle of Majuba, wherein the Transvaal won its independence back...
on the line to Natal. In later years, after being withdrawn from main line passenger service, many of these locomotives were employed in suburban and shunting service.
Gallery
The main picture shows Class 16 number 800, as built with a Belpaire firebox and Type MP1 tender, on interurban service with a destination board for Pretoria below its headlight, at Braamfontein, circa 1930.See also
- South African Class 16A 4-6-2South African Class 16A 4-6-2In 1915 the South African Railways placed two Class 16A four-cylinder simple steam locomotives with a 4-6-2 Pacific wheel arrangement in passenger train service.-Manufacturer:The Class 16A 4-6-2 Pacific locomotive was designed by D.A...
- South African Class 16B 4-6-2South African Class 16B 4-6-2In November 1917 the South African Railways placed ten Class 16B steam locomotives with a 4-6-2 Pacific wheel arrangement in passenger train service.-Manufacturer:The Class 16B 4-6-2 Pacific locomotive was designed by D.A...
- South African Class 16C 4-6-2South African Class 16C 4-6-2During 1919 the South African Railways placed ten Class 16C steam locomotives with a 4-6-2 Pacific wheel arrangement in passenger train service. Another twenty were placed in service in 1922.-Manufacturer:...
- South African Class 16D 4-6-2South African Class 16D 4-6-2In 1925 the South African Railways placed two Class 16D locomotives with a 4-6-2 Pacific wheel arrangement in passenger train service. Five more were placed in service in 1926.-Manufacturer:...
- South African Class 16DA 4-6-2South African Class 16DA 4-6-2In 1928 the South African Railways placed six Class 16DA steam locomotives with a 4-6-2 Pacific wheel arrangement in passenger train service. Eight more were placed in service in 1929, and another six in 1930.-Manufacturers:...
- South African Class 16E 4-6-2South African Class 16E 4-6-2In 1935 the South African Railways placed six Class 16E steam locomotives with a Pacific wheel arrangement in passenger train service.-Manufacturer:...
- Tender locomotive numbering and classification
- Watson Standard boilers
- The 4-6-2 "Pacific"
- List of South African locomotive classes