South African Class 8 4-8-0
Encyclopedia
In 1902 and 1903 the Cape Government Railways
placed twenty-three Class 8 steam locomotive
s with a 4-8-0
Mastodon wheel arrangement in service, three on the Cape Western System, eight on the Cape Midland System and twelve on the Cape Eastern System. In 1912, when they were assimilated into the South African Railways, they were renumbered but retained their Class 8 classification.
.
While these first Schenectady and ALCO built 2-8-0 locomotives were being subjected to exhaustive testing on all types of traffic and under varying conditions, some trouble was experienced with the leading two wheeled pony truck and, when designs were prepared at Salt River for a later order for more locomotives, the pony truck was replaced with a four wheeled bogie.
These twenty-three locomotives were the first Class 8 locomotives of the CGR to be built with a 4-8-0 Mastodon type wheel arrangement. In spite of the difference in wheel arrangement, these Consolidations and Mastodons of the CGR were all grouped together into Class 8.
They were conceived as mixed traffic locomotives equally suitable for goods and passenger work. They had larger driving wheels than the Class 7
, bar frames, used saturated steam
as built and had Stephenson valve gear
. In service it was found that the four wheeled bogies and the slightly shorter fixed wheelbase made them steadier and easier riding than their 2-8-0 predecessors.
The rest of the Class 8 Consolidations and Mastodons of the CGR, together with the Class 8-L1 to 8-L3 4-8-0 Mastodon locomotives of the Central South African Railways
, were grouped into nine more different sub-classes by the SAR. The other 4-8-0 locomotives became SAR Classes 8A to 8F and the 2-8-0 locomotives became Classes 8X to 8Z.
Of the Class 8 locomotives, five were equipped with superheated boilers, 19 inches (482.6 mm) bore cylinders and outside admission piston valves, while retaining their Class 8 classification.
Four locomotives were equipped with superheated boilers, 20 inches (508 mm) bore cylinders and inside admission piston valves and reclassified to Class 8W.
The Class 8 and Class 8W works numbers, renumbering and superheating modifications are shown in the table.
Cape Government Railways
The Cape Government Railways was the government-owned railway operator in the Cape Colony from 1874 until the creation of the South African Railways in 1910.-Private railways:...
placed twenty-three Class 8 steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...
s with a 4-8-0
4-8-0
Under the Whyte notation for the classification of steam locomotives, 4-8-0 represents the wheel arrangement of four leading wheels on two axles , eight powered and coupled driving wheels on four axles, and no trailing wheels. The type was nicknamed the Mastodon or Twelve-wheeler in North America....
Mastodon wheel arrangement in service, three on the Cape Western System, eight on the Cape Midland System and twelve on the Cape Eastern System. In 1912, when they were assimilated into the South African Railways, they were renumbered but retained their Class 8 classification.
Evolution
The first Class 8 locomotives of the Cape Government Railways (CGR) were 2-8-0 Consolidation types designed by H.M. Beatty, the Chief Locomotive Superintendent of the CGR from 1896 to 1910. It was later to become the South African Railways (SAR) Class 8XSouth African Class 8X 2-8-0
Between 1901 and 1902 the Cape Government Railways placed sixteen Class 8 2-8-0 Consolidation type steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8X...
.
While these first Schenectady and ALCO built 2-8-0 locomotives were being subjected to exhaustive testing on all types of traffic and under varying conditions, some trouble was experienced with the leading two wheeled pony truck and, when designs were prepared at Salt River for a later order for more locomotives, the pony truck was replaced with a four wheeled bogie.
These twenty-three locomotives were the first Class 8 locomotives of the CGR to be built with a 4-8-0 Mastodon type wheel arrangement. In spite of the difference in wheel arrangement, these Consolidations and Mastodons of the CGR were all grouped together into Class 8.
Manufacturer
All these locomotives were built by Neilson, Reid and Company in 1901 and 1902 and delivered in three batches in 1902 and 1903. The first batch of three, numbered 801 to 803, went to the CGR’s Western System in 1902. Of the second batch of ten that arrived in 1902, eight were numbered 358 to 365 and allocated to the Midland System, while the other two became 771 and 772, allocated to the Eastern System. The last batch of ten, numbered 773 to 782, arrived in 1903 and all went to the Eastern System.They were conceived as mixed traffic locomotives equally suitable for goods and passenger work. They had larger driving wheels than the Class 7
South African Class 7 4-8-0
In 1892 the Cape Government Railways placed six Class 7 steam locomotives with a 4-8-0 Mastodon wheel arrangement in service and between 1892 and 1893 another thirty-two were acquired. They were initially placed in service on the Cape Midland System, but were later distributed between the Cape...
, bar frames, used saturated steam
Saturated steam
In thermodynamics, the state of saturation of a fluid indicates that the fluid is at its boiling point temperature. This term can be applied in several ways:*Saturated liquid: fully in the liquid state but is about to vaporize....
as built and had Stephenson valve gear
Stephenson valve gear
The Stephenson valve gear or Stephenson link or shifting link is a simple design of valve gear that was widely used throughout the world for all kinds of steam engine. It is named after Robert Stephenson but was actually invented by his employees....
. In service it was found that the four wheeled bogies and the slightly shorter fixed wheelbase made them steadier and easier riding than their 2-8-0 predecessors.
Class 8 sub-classes
When these twenty-three locomotives were assimilated into the newly established SAR in 1912, they were renumbered 1069 to 1091, but they retained their Class 8 classification.The rest of the Class 8 Consolidations and Mastodons of the CGR, together with the Class 8-L1 to 8-L3 4-8-0 Mastodon locomotives of the Central South African Railways
Central South African Railways
From 1902 to 1904, the area of power of Lieutenant-Colonel Sir Percy Girouard later also included the lines of The Netherlands-South African Railway Company; together this dominion covered all lines in the Transvaal that belonged to NZASM ....
, were grouped into nine more different sub-classes by the SAR. The other 4-8-0 locomotives became SAR Classes 8A to 8F and the 2-8-0 locomotives became Classes 8X to 8Z.
Modification
During A.G. Watson’s term as Chief Mechanical Engineer (CME) of the SAR from 1929 to 1936, many of the Class 8 to Class 8F locomotives were equipped with superheated boilers, larger bore cylinders and either inside or outside admission piston valves. The outside admission locomotives had their cylinder bore increased from 18.5 inches (469.9 mm) to 19 inches (482.6 mm) and retained their existing SAR Class 8 classifications, while the inside admission locomotives had their cylinder bore increased to 20 inches (508 mm) and were reclassified by having a "W" suffix added to their existing SAR classifications.Of the Class 8 locomotives, five were equipped with superheated boilers, 19 inches (482.6 mm) bore cylinders and outside admission piston valves, while retaining their Class 8 classification.
Four locomotives were equipped with superheated boilers, 20 inches (508 mm) bore cylinders and inside admission piston valves and reclassified to Class 8W.
The Class 8 and Class 8W works numbers, renumbering and superheating modifications are shown in the table.
| Year |
Works No. |
CGR No. |
CGR System |
SAR No. |
SAR Model |
|---|---|---|---|---|---|
| 1901 | 6111 | 801 | Western | 1069 | |
| 1901 | 6112 | 802 | Western | 1070 | Superheated |
| 1901 | 6113 | 803 | Western | 1071 | |
| 1902 | 6216 | 358 | Midland | 1072 | |
| 1902 | 6217 | 359 | Midland | 1073 | Class 8W |
| 1902 | 6218 | 360 | Midland | 1074 | Class 8W |
| 1902 | 6219 | 361 | Midland | 1075 | |
| 1902 | 6220 | 362 | Midland | 1076 | |
| 1902 | 6221 | 363 | Midland | 1077 | Class 8W |
| 1902 | 6222 | 364 | Midland | 1078 | Class 8W |
| 1902 | 6223 | 365 | Midland | 1079 | |
| 1902 | 6224 | 771 | Eastern | 1080 | |
| 1902 | 6225 | 772 | Eastern | 1081 | |
| 1902 | 6241 | 773 | Eastern | 1082 | Superheated |
| 1902 | 6242 | 774 | Eastern | 1083 | |
| 1902 | 6243 | 775 | Eastern | 1084 | |
| 1902 | 6244 | 776 | Eastern | 1085 | Superheated |
| 1902 | 6245 | 777 | Eastern | 1086 | Superheated |
| 1902 | 6246 | 778 | Eastern | 1087 | |
| 1902 | 6247 | 779 | Eastern | 1088 | Superheated |
| 1902 | 6248 | 780 | Eastern | 1089 | |
| 1902 | 6249 | 781 | Eastern | 1090 | |
| 1902 | 6250 | 782 | Eastern | 1091 | |
Service
In SAR service, the 4-8-0 Class 8 family of locomotives served on every system in the country and in the 1920s became the mainstay of motive power on many branch lines. Their final days were spent in shunting service and by 1972 they were all withdrawn.Gallery
The main picture shows Class 8 1088, as built, at East London, circa 1930.See also
- South African Class 8A 4-8-0South African Class 8A 4-8-0In 1902 the Central South African Railways placed forty Class 8-L1 4-8-0 Mastodon steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8A.-Manufacturers:...
- South African Class 8B 4-8-0South African Class 8B 4-8-0In 1903, soon after its establishment, the Central South African Railways placed thirty Class 8-L2 4-8-0 Mastodon steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8B.-Manufacturers:Upon the...
- South African Class 8C 4-8-0South African Class 8C 4-8-0In 1903, soon after the establishment of the Central South African Railways, a second batch of thirty Cape Class 8 4-8-0 Mastodon steam locomotives were ordered and placed in service as the Class 8-L3, immediately following a previous order in that same year for a variation on the same locomotive...
- South African Class 8D 4-8-0South African Class 8D 4-8-0In 1903, when the first batch of Class 8 4-8-0 Mastodons had been tried and proven successful, the Cape Government Railways placed another thirty-eight Class 8 4-8-0 steam locomotives in service, six on the Cape Western System, twenty on the Cape Midland System and twelve on the Cape Eastern System...
- South African Class 8E 4-8-0South African Class 8E 4-8-0In 1903, at the same time that the Cape Government Railways ordered its second batch of thirty-eight Class 8 4-8-0 Mastodon steam locomotives, four additional locomotives of the same class were ordered, but built to modified specifications in order to accommodate a larger grate area...
- South African Class 8F 4-8-0South African Class 8F 4-8-0In 1904 the Cape Government Railways placed its final batch of ten Class 8 4-8-0 Mastodon steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8F.-Evolution:...
- South African Class 8X 2-8-0South African Class 8X 2-8-0Between 1901 and 1902 the Cape Government Railways placed sixteen Class 8 2-8-0 Consolidation type steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8X...
- South African Class 8Y 2-8-0South African Class 8Y 2-8-0In 1903 the Cape Government Railways placed four more Cape Class 8 2-8-0 steam locomotives in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8Y.-Manufacturer:...
- South African Class 8Z 2-8-0South African Class 8Z 2-8-0In 1904 the Cape Government Railways placed its last eight Class 8 2-8-0 Consolidation type steam locomotives in service. All subsequent Cape Class 8 locomotives were built with a 4-8-0 Mastodon wheel arrangement...
- Tender locomotive numbering and classification
- The 4-8-0 "Mastodon"
- List of South African locomotive classes