South African Class 8D 4-8-0

In 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. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8D.^[6][7][4]

Manufacture

Evolution

The first Class 8 locomotive of the Cape Government Railways (CGR) was a 2-8-0 Consolidation type 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 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, it was replaced with a four wheeled bogie.^[7]

These thirty-eight locomotives were the second batch of CGR Class 8 locomotives to be built with a 4-8-0 Mastodon type wheel arrangement. In spite of the difference in wheel arrangement, the CGR’s new post Class 7 Consolidations and Mastodons were all grouped together into Class 8.^[7][6]

Builders

They were ordered from Neilson, Reid and Company in 1902 and delivered in four batches in 1903. While they were being built, Neilson, Reid amalgamated with Dübs and Company and Sharp Stewart and Company to form the North British Locomotive Company (NBL). As a result, the last four of these locomotives were delivered as having been built by NBL at the Hyde Park shops of the former Neilson, Reid.^[7]

The locomotives were distributed between the CGR’s Midland, Eastern and Western systems as follows:

• Twenty were allocated to the Midland System, with nineteen of them numbered 366 to 384 and the twentieth numbered 399.
• Twelve, numbered 783 to 794, went to the Eastern System.
• Six, numbered 807 to 812, went to the Western System.^[7][5]

Class 8 sub-classes

When these thirty-eight locomotives were assimilated into the newly established SAR in 1912, they were renumbered 1192 to 1229 and reclassified to Class 8D.^[5]

These locomotives, together with the rest of the CGR’s Class 8 2-8-0 Consolidations and Class 8 4-8-0 Mastodons and the Class 8-L1 to 8-L3 4-8-0 Mastodon locomotives from the Central South African Railways (CSAR), were grouped into ten different sub-classes by the SAR. The 4-8-0 locomotives became SAR Classes 8 and 8A to 8F and the 2-8-0 locomotives became Classes 8X to 8Z.^[3]

Modification

During A.G. Watson’s term as the 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 valve locomotives had their cylinder bore increased from 18.5 inches (470 millimetres) to 19 inches (483 millimetres) and retained their existing SAR classifications, while the inside admission valve locomotives had their cylinder bore increased to 20 inches (508 millimetres) and were reclassified by having a "W" suffix added to their existing SAR classifications.^[3][6]

Of the Class 8D locomotives, nine were equipped with superheated boilers, 19 inches (483 millimetres) bore cylinders and outside admission piston valves while retaining their Class 8D classification.^[3]

Fourteen were equipped with superheated boilers, 20 inches (508 millimetres) bore cylinders and inside admission piston valves, and were reclassified to Class 8DW.^[3]

The Class 8D and Class 8DW locomotive builders, works numbers, CGR to SAR renumbering and superheating modifications are shown in the table.^[1][2][3][4]

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, some being sold into industry, like number 1211 which became "Puffing Duggie" at Grootvlei Proprietary Mines (GVPM).^[6][8]

Gallery

The main picture shows reboilered and modified SAR Class 8D 1223 at the Bloemfontein locomotive depot on 22 March 1970. The same locomotive is depicted below before the modification.

See also

• South African Class 8 4-8-0
• South African Class 8A 4-8-0
• South African Class 8B 4-8-0
• South African Class 8C 4-8-0
• South African Class 8E 4-8-0
• South African Class 8F 4-8-0
• South African Class 8X 2-8-0
• South African Class 8Y 2-8-0
• South African Class 8Z 2-8-0
• Tender locomotive numbering and classification
• The 4-8-0 "Mastodon"
• List of South African locomotive classes

References

1. ^ ^{a b c} Neilson, Reid works list, compiled by Austrian locomotive historian Bernhard Schmeiser
2. ^ ^{a b c} North British Locomotive Company works list, compiled by Austrian locomotive historian Bernhard Schmeiser
3. ^ ^{a b c d e f} South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
4. ^ ^{a b c} Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 9, 12, 15, 42-43 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
5. ^ ^{a b c} Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. p. 139. ISBN 0715354272. 
6. ^ ^{a b c d e} Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 48-49. ISBN 0869772112. 
7. ^ ^{a b c d e} Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 63-64. ISBN 0715353829. 
8. ^ Middleton, John N. (2002). Railways of Southern Africa Locomotive Guide - 2002 (as amended by Combined Amendment List 4, January 2009) (2nd, Dec 2002 ed.). Herts, England: Beyer-Garratt Publications. pp. 14, 19.