South African Class 2 4-6-2

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This article is about one of two different Natal Government Railways locomotive types to be designated "Class A". For the other, see South African Class 2C 4-6-2.
NGR Class A 4-6-2 1905
South African Class 2 4-6-2
SAR Klasse 2.jpg
NGR Class A no. 326, SAR Class 2 no. 763
Type and origin
Power type Steam
Designer Natal Government Railways
(D.A. Hendrie)
Builder North British Locomotive Company
Serial number 16192-16193
Model NGR Hendrie A
Build date 1904
Total produced 2
Specifications
Configuration 4-6-2 (Pacific)
Driver 2nd coupled axle
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Leading dia. 28 12 in (724 mm)
Coupled dia. 51 in (1,295 mm)
Trailing dia. 30 in (762 mm)
Tender wheels 30 in (762 mm)
Wheelbase 51 ft 1 38 in (15,580 mm)
 • Engine 27 ft 10 in (8,484 mm)
 • Leading 6 ft (1,829 mm)
 • Coupled 9 ft 4 in (2,845 mm)
 • Tender 15 ft 6 in (4,724 mm)
 • Tender bogie 4 ft 6 in (1,372 mm)
Length:
 • Over couplers 58 ft 4 18 in (17,783 mm)
Height 12 ft 6 in (3,810 mm)
Frame type Plate
Axle load 15 LT (15,240 kg)
 • Leading 11 LT 15 cwt (11,940 kg)
 • 1st coupled 14 LT (14,220 kg)
 • 2nd coupled 15 LT (15,240 kg)
 • 3rd coupled 14 LT 15 cwt (14,990 kg)
 • Trailing 10 LT 16 cwt (10,970 kg)
 • Tender bogie Bogie 1: 18 LT 18 cwt (19,200 kg)
Bogie 2: 19 LT 1 cwt (19,360 kg)
 • Tender axle 9 LT 10 cwt 2 qtr (9,678 kg)
Adhesive weight 43 LT 15 cwt (44,450 kg)
Loco weight 66 LT 6 cwt (67,360 kg)
Tender weight 37 LT 19 cwt (38,560 kg)
Total weight 104 LT 5 cwt (105,900 kg)
Tender type SH (2-axle bogies)
SH, SK permitted
Fuel type Coal
Fuel capacity 6 LT (6.1 t)
Water cap 3,225 imp gal (14,700 l)
Firebox type Belpaire
 • Firegrate area 28 sq ft (2.6 m2)
Boiler:
 • Pitch 7 ft 3 in (2,210 mm)
 • Diameter 5 ft 34 in (1,543 mm)
 • Tube plates 16 ft 4 34 in (4,997 mm)
 • Small tubes 246: 2 in (51 mm)
Boiler pressure 180 psi (1,241 kPa)
Safety valve Ramsbottom
Heating surface 2,231 sq ft (207.3 m2)
 • Tubes 2,112 sq ft (196.2 m2)
 • Firebox 119 sq ft (11.1 m2)
Cylinders Two
Cylinder size 19 in (483 mm) bore
24 in (610 mm) stroke
Valve gear Stephenson
Valve type Balanced slide
Couplers Johnston link-and-pin
AAR knuckle (1930s)
Performance figures
Tractive effort 22,940 lbf (102.0 kN) @ 75%
Career
Operators Natal Government Railways
South African Railways
Class NGR Class A
SAR Class 2
Number in class 2
Numbers NGR 325-326
SAR 762-763
Nicknames Hendrie A
Delivered 1905
First run 1905
Withdrawn 1936
The 2nd coupled axle had flangeless wheels

The South African Railways Class 2 4-6-2 of 1905 was a steam locomotive from the pre-Union era in the Colony of Natal.

In 1905, the Natal Government Railways placed two Class A steam locomotives with a 4-6-2 Pacific type wheel arrangement in service. In 1912, when these locomotives were assimilated into the South African Railways, they were renumbered and designated Class 2.[1][2][3][4]

Manufacturer[edit]

In 1904, orders were placed with the North British Locomotive Company (NBL) for two 4-6-2 Pacific type locomotives for the Natal Government Railways (NGR). They were designed by NGR Locomotive Superintendent D.A. Hendrie for passenger traffic on those sections of the mainline between Ladysmith and Charlestown which did not have very severe gradients. When they were delivered and placed in service early in 1905, they were designated the NGR Class A, also commonly known as the Hendrie A, and numbered 325 and 326.[2][4][5]

Characteristics[edit]

The boiler of this Class was noted for its free steaming qualities. The engines used saturated steam, had Stephenson valve gear and were built on plate frames. The cylinders were inclined 1 in 18 and were arranged outside the plate frames, while the balanced slide valves were arranged inside the frames. After these two engines, Hendrie adopted Walschaerts valve gear and outside valves on all his subsequent locomotive designs for its greater accessibility.[1][2][4]

D.A. Hendrie

The locomotives had Belpaire fireboxes with firebar rocking finger grates. To accommodate the wide and deep firebox, Hendrie made use of a bridle casting along the same lines as the one which was first introduced by H.M. Beatty on his Cape Government Railways (CGR) 6th Class 2-6-2 of 1903, later the Class 6Y on the South African Railways (SAR).[1][2]

With a bridle casting, the widening of the locomotive frame at the back end was accomplished by uniting the narrow front part of the frame and the wider rear part by the heavy steel casting. This method of widening the frames for the firebox continued on the SAR until the general adoption of bar frames for mainline locomotives by 1927 rendered it no longer necessary.[1][2]

Service[edit]

Natal Government Railways[edit]

The two locomotives ran their first trials on 31 January and 3 March 1905 respectively. As intended, they were placed in service between Ladysmith and Charlestown and were shedded at Charlestown. They worked the mail trains on this section for many years.[1][2][4]

South African Railways[edit]

When the Union of South Africa was established on 31 May 1910, the three Colonial government railways (CGR, NGR 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.[3][6]

In 1912, these two Pacifics were renumbered 762 and 763 and designated Class 2 on the SAR.[3][4][7]

They were later transferred to the Witwatersrand for a short period, after which they worked on the Komatipoort-Waterval Boven section until they were withdrawn by 1936.[1][4]

References[edit]

  1. ^ a b c d e f Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 101–102. ISBN 978-0-7153-5382-0. 
  2. ^ a b c d e f Espitalier, T.J.; Day, W.A.J. (1944). The Locomotive in South Africa - A Brief History of Railway Development. Chapter III - Natal Government Railways (Continued). South African Railways and Harbours Magazine, July 1944. pp. 505-506.
  3. ^ a b c Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 7, 12, 15, 35 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
  4. ^ a b c d e f Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 35–36. ISBN 0869772112. 
  5. ^ North British Locomotive Company works list, compiled by Austrian locomotive historian Bernhard Schmeiser
  6. ^ The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.
  7. ^ Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. p. 137. ISBN 978-0-7153-5427-8.