| CGR 8th Class 4-8-0 1902 South African Classes 8 and 8W 4-8-0 | |
| Hatnote: | ♠ Original locomotive, as built Superheated, outside admission valves Superheated, inside admission valves, Class 8W ʘ XD tender - XE1 tender - XF tender |
| Powertype: | Steam |
| Designer: | Cape Government Railways (H.M. Beatty) |
| Builder: | Neilson, Reid and Company |
| Serialnumber: | 6111-6113, 6216-6225, 6241-6250 |
| Buildmodel: | CGR 8th Class (4-8-0) |
| Builddate: | 1901-1902 |
| Totalproduction: | 23 |
| Whytetype: | 4-8-0 (Mastodon) |
| Uicclass: | ♠ 2'Dn2 - 2'Dh2 |
| Driver: | 2nd coupled axle |
| Leadingdiameter: | NaN0NaN0 |
| Coupleddiameter: | 480NaN0 |
| Tenderdiameter: | ʘ NaN0NaN0 as built ʘ 340NaN0 retyred |
| Wheelbase: | 46feet |
| Engine Total: | 23feet |
| Leading: | 60NaN0 |
| Coupled: | 13feet |
| Tender Total: | ʘ 14feet |
| Tenderbogie: | ʘ 4feet |
| Over Couplers: | 54feet |
| Height: | ♠ 12feet 12feet |
| Frametype: | Bar |
| Axleload: | ♠ 11lt 12sigfig=4NaNsigfig=4 12lt |
| Leadingbogie/Pony: | ♠ 12lt 12lt |
| Coupled All: | ♠ 11lt 12sigfig=4NaNsigfig=4 |
| Coupled 1: | 11lt |
| Coupled 2: | 12lt |
| Coupled 3: | 11lt |
| Coupled 4: | 11lt |
| Tenderbogieload: | Bogie 1: ʘ 16lt 20lt Bogie 2: ʘ 17lt 22lt |
| Tenderaxle: | ʘ 8lt 9lt av. 11lt |
| Weightondrivers: | ♠ 46lt 48sigfig=4NaNsigfig=4 48lt |
| Locoweight: | ♠ 59lt 60lt 61lt |
| Tenderweight: | ʘ 34lt 36lt 43lt |
| Locotenderweight: | ♠ʘ 93lt ♠ 96lt ♠ 102lt ʘ 94lt 103lt ʘ 95lt 97lt |
| Tendertype: | ʘ XD (2-axle bogies) XE1 (2-axle bogies) XF (2-axle bogies) XC, XC1, XD, XE, XE1, XF, XF1, XF2, XJ, XM, XM1, XM2, XM3 permitted |
| Fueltype: | Coal |
| Fuelcap: | ʘ 5lt 101NaN1 |
| Watercap: | ʘ 2730sigfig=3NaNsigfig=3 2855sigfig=3NaNsigfig=3 3000sigfig=3NaNsigfig=3 |
| Fireboxtype: | Round-top |
| Firearea: | ♠ 21.352NaN2 212NaN2 |
| Pitch: | ♠ 70NaN0 7feet |
| Diameterinside: | 50NaN0 |
| Lengthinside: | ♠ 11feet 11feet |
| Smalltubediameter: | ♠ 205: 20NaN0 115: 20NaN0 |
| Largetubediameter: | 18: NaN0NaN0 |
| Boilerpressure: | 1800NaN0 |
| Safetyvalvetype: | Ramsbottom |
| Totalsurface: | ♠ 1315square feet 1081square feet |
| Tubearea: | ♠ 1184square feet 950square feet |
| Fireboxarea: | 131square feet |
| Superheaterarea: | 214square feet |
| Cylindercount: | Two |
| Cylindersize: | ♠ NaN0NaN0 bore 190NaN0 bore 200NaN0 bore ♠ 240NaN0 stroke |
| Valvegear: | Stephenson |
| Valvetype: | ♠ Slide - Piston |
| Coupling: | Johnston link-and-pin AAR knuckle (1930s) |
| Tractiveeffort: | ♠ 23110lbf @ 75% 24370lbf @ 75% 27000lbf @ 75% |
| Operator: | Cape Government Railways South African Railways |
| Operatorclass: | CGR 8th Class SAR Classes 8 & 8W |
| Numinclass: | 23 |
| Fleetnumbers: | CGR 358-365, 771-782, 801-803 SAR 1069-1091 |
| Deliverydate: | 1902-1903 |
| Firstrundate: | 1902 |
| Withdrawndate: | 1972 |
| Notes: | The leading coupled axle had flangeless wheels |
The South African Railways Class 8 4-8-0 of 1902 was a steam locomotive from the pre-Union era in the Cape of Good Hope.
In 1902 and 1903, the Cape Government Railways placed 23 8th Class steam locomotives with a Mastodon type 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.[1]
The first 8th Class locomotives of the Cape Government Railways (CGR) were Consolidation types, designed by H.M. Beatty, the Chief Locomotive Superintendent of the CGR from 1896 to 1910. They entered service in 1901 and were later to become the South African Railways (SAR) Class 8X.
While these first Schenectady and ALCO-built 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. When designs were prepared at Salt River for a later order for more locomotives, the pony truck was replaced with a four-wheeled bogie and the coupled wheelbase was shortened from 14feet to 13feet.
The 23 locomotives of 1902 and 1903 were the first 8th Class locomotives of the CGR to be built with a Mastodon type wheel arrangement. These locomotives were built by Neilson, Reid and Company in 1901 and 1902, and delivered in three batches in 1902 and 1903. In spite of the difference in wheel arrangement, these Mastodons and the earlier Consolidations of the CGR were all grouped together into the 8th Class.
They were conceived as mixed traffic locomotives, equally suitable for goods and passenger work. They had larger coupled wheels than the CGR 7th Class, bar frames, used saturated steam and had Stephenson valve gear. In service, it was found that the four-wheeled bogies and the 120NaN0 shorter fixed wheelbase made them steadier and easier riding than their Consolidation predecessors.
The first batch of three locomotives, numbered in the range from 801 to 803, went to the CGR's Western System in 1902. They were delivered with Type XD tenders which had a coal capacity of 5lt and a water capacity of 2730sigfig=3NaNsigfig=3.[2]
Of the second batch of ten locomotives which arrived in 1902, eight were numbered in the range from 358 to 365 and allocated to the Midland System, while the other two became numbers 771 and 772, allocated to the Eastern System. These engines were delivered with Type XE1 tenders which had a coal capacity of 101NaN1 and a water capacity of 2855sigfig=3NaNsigfig=3.[2] [3] [4]
The last batch of ten locomotives, numbered in the range from 773 to 782, arrived in 1903 and all went to the Eastern System. These engines were delivered with Type XF tenders which also had a coal capacity of 101NaN1, but a water capacity of 3000sigfig=3NaNsigfig=3.[2] [3] [4]
When the Union of South Africa was established on 31 May 1910, the three Colonial government railways (CGR, Natal Government Railways and Central South African Railways) were united under a single administration to control and administer the railways, ports and harbours of the Union. Although the South African Railways and Harbours came into existence in 1910, the actual classification and renumbering of all the rolling stock of the three constituent railways were only implemented with effect from 1 January 1912.[1] [5]
When these 23 locomotives were assimilated into the South African Railways (SAR) in 1912, they were renumbered in the range from 1069 to 1091, but they retained their Class 8 classification.[1]
The rest of the 8th Class Consolidations and Mastodons of the CGR, together with the Class 8-L1 to 8-L3 Mastodon locomotives of the Central South African Railways, were grouped into nine more different sub-classes by the SAR. The other locomotives became SAR Classes 8A to 8F and the 2-8-0 locomotives became Classes 8X to 8Z.[3] [4]
During A.G. Watson's term as Chief Mechanical Engineer 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 NaN0NaN0 to 190NaN0 and retained their existing SAR Class 8 classifications, while the inside admission locomotives had their cylinder bore increased to 200NaN0 and were reclassified by having a "W" suffix added to their existing SAR classification letters.[3] [4]
Of the Class 8 locomotives, five were equipped with superheated boilers, 190NaN0 bore cylinders and outside admission piston valves, while retaining their Class 8 classification.[3] [4]
Four locomotives were equipped with superheated boilers, 200NaN0 bore cylinders and inside admission piston valves and reclassified to Class 8W.[3] [4]
In SAR service, the 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. From Volksrust in the Western Transvaal system, the Class 8 worked the 171km (106miles) link line to Bethal for several decades until the end of the 1950s, initially sharing their duties with some versions of the Class 6 family. In their last decade at Volksrust until mid-1961 they were increasingly used on standby and shunting duties while the 1948 batch of North British-built Class 19D locomotives were phased in. By 1972, they were all withdrawn from service.[6]
Only one member of this class survives, Class 8 no. 1090 formerly Cape Government Railways Eastern no. 781 is preserved under ownership of TRANSnet at Louis Trichaart Station. [7]
The Class 8 and Class 8W works numbers, renumbering and superheating modifications are shown in the table.[1] [2] [3] [4]
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 | |
The main picture shows Class 8 no. 1088, ex CGR no. 779, at East London c. 1930, as built with slide valves, but with a rebuilt Type XF tender. The following pictures serve to illustrate the original slide valve configuration and the modified piston valve and superheating configuration.