South African Class 17 4-8-0TT

South African Class 17 4-8-0TT

SAR Class 17 no. 1432, circa 1930
Type and origin
Power type Steam
Designer Natal Government Railways
Builder Dübs and Company
Serial number See table
Model NGR Class D2
Build date 1888-1915
Total produced 102
Rebuilder South African Railways
Rebuild date 1926-1929
Number rebuilt 21
Specifications
Configuration 4-8-0TT "Mastodon"
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Leading wheel
diameter		 25 3⁄4 in (654 mm)
Driver diameter 39 in (991 mm)
Wheelbase Total: 44 ft 11 1⁄2 in (13.703 m)
Engine:
5 ft (1.524 m) bogie
11 ft (3.353 m) coupled
19 ft 9 in (6.020 m) total
Type ZC Tender:
4 ft 7 in (1.397 m) bogie
16 ft 1 in (4.902 m) total
Type YC Tender:
10 ft (3.048 m)
Length 52 ft 2 3⁄8 in (15.910 m) total
Height 12 ft 2.5 in (3.721 m)
Axle load 8.5 long tons (8.6 t) on 2nd driver
Weight on drivers 32.9 long tons (33.4 t)
Locomotive weight 42.2 long tons (42.9 t)
Tender weight 38,960 lb (17.7 t) empty
34.1 long tons (34.6 t) w/o
Locomotive and tender
combined weight		 76.3 long tons (77.5 t) w/o
Tender type ZC or YC - Probable types YB, YC, YE, YE1, XC1, ZC
Type ZC:
* 2 axle bogies
* 34 in (864 mm) wheels
* Length 23 ft 8 7⁄8 in (7.236 m)
Type YC:
* 3 axle tender
* 37 in (940 mm) wheels
* Length 21 ft 2 7⁄8 in (6.474 m)
Fuel type Coal
Fuel capacity Type ZC: 5 1⁄2 long tons (5.6 t)
Type YC: 7 1⁄2 long tons (7.6 t)
Water capacity 2,600 imp gal (12,000 l) tender
1,358 imp gal (6,170 l) engine tanks
Boiler 3 ft 1 3⁄4 in (0.959 m) inside diameter
10 ft 10 1⁄8 in (3.305 m) inside length
7 ft (2.134 m) pitch
Boiler pressure 160 psi (1,100 kPa)
Firegrate area 24 sq ft (2.230 m2)
Heating surface:
– Tubes		 187 tubes 1 3⁄4 in (44.4 mm) diameter
930 sq ft (86.400 m2)
– Firebox 62 sq ft (5.760 m2)
– Total 992 sq ft (92.160 m2)
Cylinders Two
Cylinder size 17 in (432 mm) bore
21 in (533 mm) stroke
Valve gear Stephenson
Performance figures
Tractive effort 18,670 lbf (83 kN) at 75% pressure
Career
Operator(s) South African Railways [1]
Class Class 17
Number in class 21
Number(s) 1415–1435
Delivered 1926-1929
First run 1888
Retired 1961 [2]

The South African Class 17 4-8-0TT of 1926 is a South African steam locomotive from the South African Railways era.

Between 1926 and 1929, to address a shortage of suitable shunting locomotives, the South African Railways rebuilt twenty-one ex Natal Government Railways Class D2 4-8-2 Mountain type tank steam locomotives to Class 17 4-8-0 Mastodon type tank-and-tender locomotives.[1][2]

Manufacturers

The Natal Government Railways (NGR) Class D 4-8-2 Mountain type tank locomotive was designed by William Milne, the locomotive superintendent of the NGR from 1877 to 1896, and built by Dübs and Company. One hundred of these locomotives were delivered in ten batches by Dübs between 1888 and 1899, and in 1915 another two were built from spare parts by the South African Railways (SAR) in their Durban shops.[3]

Modifications

Belpaire firebox

Beginning in 1905 these NGR Class D locomotives, also known on the NGR as the "Dübs A", were gradually fitted with Belpaire fireboxes with wider grates. The unmodified locomotives then became the NGR Class D1 while the modified locomotives with Belpaire fireboxes became the Class D2. In later SAR service the NGR Class D1 and D2 were both designated Class A and the modified locomotives were referred to as Class A Belpaire.[3][4]

Rebuilding

NGR Class D2 no. 105, c. 1900

When a shortage of suitable shunting locomotives developed as a result of increasing traffic throughout the country and particularly on the Witwaters­rand, the SAR modified twenty-one of the Class A Belpaire 4-8-2 Mountain type tank locomotives between 1926 and 1929 by removing the trailing bissel bogie and the coal bunker, shortening the main frame and adding a tender to increase the coal and water capacity, thereby converting them to 4-8-0 Mastodon type tank-and-tender locomotives.[5][6]

Tenders from various scrapped locomotive types were used. The tender depicted in the main picture appears to be a Type YC three-axle tender. Other similar tender types that were possibly used were Types YB, YE and YE1, also three-axle tenders, while the official SAR locomotive diagram depicts either a Type XC1 or Type ZC tender with four axles on two bogies.[1][2]

Service

These twenty-one rebuilt 4-8-2T locomotives were reclassified to Class 17 and renumbered in the range from 1415 to 1435. They were employed as shunting engines around Durban and Port Elizabeth and were withdrawn from service by 1961, more than seventy years after the first one was built.[2][6]

In November 1953 two of these locomotives, numbers 1423 and 1431, were purchased by the Zambezi Saw Mills Company for use on their Livingstone-Mulobezi logging railway in Northern Rhodesia, where they were scrapped between 1961 and 1963.

Works numbers and renumbering

See also

References

  1. ↑ 1.0 1.1 1.2 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, pp. 21 & 21A, as amended
  2. ↑ 2.0 2.1 2.2 2.3 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 10–11, 26–27, 68. ISBN 0869772112.
  3. ↑ 3.0 3.1 Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 90–91. ISBN 978-0-7153-5382-0.
  4. ↑ The Railway Report for year ending 31 Dec. 1908, Natal Government Railways, p. 39, par 14.
  5. ↑ Whyte notation suffixes
  6. ↑ 6.0 6.1 Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. p. 63. ISBN 978-0-7153-5427-8.