South African Class 8A 4-8-0

From Wikipedia, the free encyclopedia
Jump to: navigation, search
South African Class 8A 4-8-0
& South African Class 8AW 4-8-0
ex IMR 8th Class 4-8-0
ex CSAR Class 8-L1 4-8-0
SAR Class 8A 1106 Breyten 040481.jpg
Ex CSAR Class 8-L1 no. 415, SAR Class 8A no. 1106, at Breyten, Transvaal, 4 April 1981
Type and origin
Power type Steam
Designer Cape Government Railways
Builder Neilson, Reid and Company
Sharp, Stewart and Company
Serial number Neilson, Reid 6176-6195 [1]
Sharp, Stewart 4848-4867
Model CGR 8th Class (4-8-0)
Build date 1902 [1][2]
Total produced 40
Specifications
Configuration 4-8-0 "Mastodon"
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Leading wheel
diameter
28.5 in (724 mm)
Driver diameter 48 in (1,220 mm)
Wheelbase Total: 46 ft 10.5 in (14.288 m)
Engine:
6 ft (1.829 m) bogie
13 ft 6 in (4.115 m) coupled
23 ft 3 in (7.087 m) total
Tender:
4 ft 7 in (1.397 m) bogie
14 ft 7 in (4.445 m) total
Length 54 ft 5 in (16.586 m)
Height As built:
12 ft 10 in (3.912 m)
Superheated & Class 8AW:
12 ft 8 in (3.861 m)
Frame Bar frame
Axle load As built:
11.8 long tons (12.0 t) on all but 3rd driver
Superheated:
12 long tons (12.2 t) per driver
Class 8AW:
12.55 long tons (12.8 t) on 2nd driver
Weight on drivers 46.8 long tons (47.6 t) as built
48 long tons (48.8 t) superheated
48.3 long tons (49.1 t) Class 8AW
Locomotive weight 58.65 long tons (59.6 t) as built
60.75 long tons (61.7 t) superheated
61.05 long tons (62.0 t) Class 8AW
Tender weight 44,032 lb (20.0 t) empty
43.05 long tons (43.7 t) w/o
Locomotive and tender
combined weight
114,464 lb (51.9 t) empty
101.7 long tons (103.3 t) as built
103.8 long tons (105.5 t) superheated
104.1 long tons (105.8 t) Class 8AW
Tender type XF - XC, XC1, XD, XE, XE1, XF, XF1, XF2, XJ, XN, XN1, XM2, XM3 permitted
* 2 axle bogies
* 34 in (864 mm) wheels
* Length 22 ft 2.5 in (6.769 m)
Fuel type Coal
Fuel capacity 10 long tons (10.2 t)
Water capacity 3,000 imp gal (14,000 l)
Boiler 5 ft (1.524 m) inside diameter
11 ft 0.375 in (3.362 m) inside length
7 ft (2.134 m) pitch, as built
7 ft 1 in (2.159 m) pitch, superheated & Class 8AW
Boiler pressure 180 psi (1,240 kPa)
Firegrate area 21 sq ft (1.951 m2)
Heating surface:
– Tubes
As built:
205 tubes 2 in (50.8 mm) diameter
1,184 sq ft (109.997 m2)
Superheated & Class 8AW:
115 tubes 2 in (50.8 mm) diameter
18 tubes 5.5 in (140 mm) diameter
950 sq ft (88.258 m2)
– Firebox 131 sq ft (12.170 m2)
– Total 1,315 sq ft (122.167 m2) as built
1,081 sq ft (100.428 m2) superheated & Class 8AW
Superheater type Not equipped as built
Superheater area 214 sq ft (19.881 m2) superheated & Class 8AW
Cylinders Two
Cylinder size As built: 18.5 in (470 mm) bore
Superheated: 19 in (483 mm) bore
Class 8AW: 20 in (508 mm) bore
All: 24 in (610 mm) stroke
Valve gear Stephenson
Performance figures
Tractive effort At 75% boiler pressure:
23,100 lbf (102.8 kN) as built
24,370 lbf (108.4 kN) superheated
27,000 lbf (120.1 kN) Class 8AW [3]
Career
Operator(s) Imperial Military Railways
Central South African Railways
South African Railways
Zambesi Saw Mills
Zambia Railways
Class IMR 8th Class
CSAR Class 8-L1
SAR Class 8A, Class 8AW
Number in class 40
Number(s) CSAR 401-440
SAR 1092-1131 [4][5]
Delivered 1902
First run 1902
Withdrawn 1972 [6]

The South African Class 8A 4-8-0 of 1902 is a South African steam locomotive from the pre-Union era in the Transvaal.

In 1902 the Imperial Military Railways placed forty Cape Eighth Class 4-8-0 Mastodon type steam locomotives in service. In that same year, when the Central South African Railways was established, they were designated Class 8-L1. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 8A.[2][6]

Manufacturers[edit]

Due to the shortage of locomotives brought about by wartime conditions during the Second Freedom War, the Imperial Military Railways (IMR) placed orders for forty Cape Eighth Class locomotives with two Scottish locomotive manufacturers in 1901. They were built to the specifications of the 8th Class 4-8-0 Mastodon type designed by H.M. Beatty, the chief locomotive superintendent of the Cape Government Railways (CGR) from 1896 to 1910, and were the last locomotives to be ordered under the military administration.[2][6]

With the cessation of hostilities in June 1902, the working of all railways in the Transvaal and Orange Free State was handed over to civil control. On 1 July 1902 the IMR became the Central South African Railways (CSAR) and the forty locomotives therefore came onto the CSAR roster, where they were designated Class 8-L1. The twenty built by Neilson, Reid and Company were numbered in the range from 401 to 420, and the twenty by Sharp, Stewart and Company were numbered in the range from 421 to 440.[2][6]

Reclassification[edit]

The Union of South Africa was established on 31 May 1910, in terms of the South Africa Act. One of the clauses in the Act required that the three Colonial Government railways, the Cape Government Railways, the Natal Government Railways and the CSAR, also be united under one single administration to control and administer the railways, ports and harbours of the Union. While the South African Railways (SAR) came into existence in 1910, the actual classification and renumbering of all the rolling stock of the three constituent railways required careful planning and was only implemented with effect from 1 January 1912.[4][7]

When these forty locomotives were assimilated into the SAR in 1912, they were renumbered in the range from 1092 to 1131 and reclassified to Class 8A.[4][5][6]

All the CGR’s 8th Class 2-8-0 Consolidation types and 8th Class 4-8-0 Mastodon types, together with the CSAR’s Class 8-L2 and 8-L3 4-8-0 Mastodon type locomotives, 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[edit]

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

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

The Classes 8A and 8AW builders, works numbers, renumbering and superheating modifications are shown in the table.[1][3][4]

Service[edit]

Government railways[edit]

In SAR service, the 4-8-0 Class 8 family of locomotives served on every system in the country and in the 1920s it became the mainstay of motive power on many branchlines. Their final days were spent in shunting service and by 1972 they were all withdrawn.[6]

Industrial[edit]

In November 1971 one Class 8A locomotive, number 1126, was sold to the Zambesi Saw Mills (ZSM) in Zambia. This was the last locomotive to be purchased by this logging company that worked the teak forests that stretched 100 miles (160 kilometres) to the north-west of Livingstone in Zambia. It had built one of the longest logging railways in the world to serve its sawmill at Mulobezi.[8]

Railway operations ceased at Mulobezi around 1972, whilst operation of the line to Livingstone was taken over by the Zambia Railways (ZR) in 1973. Number 1126 was employed as a shunter at Mulobezi after logging operations had ceased and the ZR had taken over the mainline. It was returned to Livingstone in December 1975 and eventually, in June 1983, it went to the Railway Museum at Livingstone.[8]

Service illustrated[edit]

The main picture shows SAR Class 8A no. 1106 at Breyten, Transvaal on 4 April 1981, before it was plinthed at Ermelo. The original appearance of the cylinders and the appearance of the modified outside admission valve cylinders after modification are illustrated by the pictures below.[9]

See also[edit]

References[edit]

  1. ^ a b c Neilson, Reid works list, compiled by Austrian locomotive historian Bernhard Schmeiser
  2. ^ a b c d Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 124–126. ISBN 978-0-7153-5382-0. 
  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 d Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 8, 12, 15, 40-41 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
  5. ^ a b 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 978-0-7153-5427-8. 
  6. ^ a b c d e f g Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 48–49. ISBN 0869772112. 
  7. ^ The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.
  8. ^ a b "Sitimela", a history of the Zambezi Saw Mills Logging Railway, 1911-1972, Geof M Calvert, 2005, published by the Barotse Development Trust, p86, ISBN 0-7974-2837-2
  9. ^ 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. p. 18.