NGR 4-6-2T (Hunslet)
| NGR 4-6-2T (Hunslet) SAR No.NG 1 and 2 |
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|---|---|
 NGR class N 4-6-2T No. 2
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| Number: | 2 |
| Manufacturer: | Hunslet |
| Year of construction (s): | 1907 |
| Retirement: | SAR 1915 |
| Type : | 2'C1 'n2t |
| Gauge : | 610 mm |
| Length over coupling: | 7,328 mm |
| Service mass: | 24.3 t |
| Friction mass: | approx. 16 t |
| Wheel set mass : | 5.55 t |
| Driving wheel diameter: | 762 mm |
| Cylinder diameter: | 292 mm |
| Piston stroke: | 381 mm |
| Boiler overpressure: | 113.7 N / cm² |
| Grate area: | 1.2 m² |
| Train brake: | Suction air brake |
The 4-6-2T locomotives built by Hunslet for Natal Government Railways (NGR) were the first 610mm narrow gauge locomotives in Natal .
The tank locomotives were built for the route between Estcourt and Weenen . Hunslet supplied two copies in 1907 based on a design by DA Hendrie, the chief mechanical engineer of the NGR.
The wheel arrangement of the locomotives was 2'C1 '(English 4-6-2T), so they had a leading bogie , three coupled axles and a trailing axle. The coupling axles were mounted in an external plate frame and the cylinders, which were also external, worked on crank webs. The controls were of the Walschaerts design, and flat slide valves were sufficient for the wet steam locomotives.
The side water boxes extended the entire length of the boiler including the smoke chamber ; the coal store was housed in front of the driver's cab. This was open at the back and sides, the only panes were two round "portholes" on the front.
After the Natal Government Railway was absorbed into the newly founded South African Railways (SAR), the locomotives were given the numbers NG 1 and 2 . ( NG stands for Narrow Gauge ). Because the SAR's narrow-gauge locomotives were not classified until the end of the 1920s and the locomotives had already been retired in 1915, they were no longer given a class designation.
After retirement, the locomotives were sold to Portuguese East Africa (now Mozambique ), where their track is lost.
Based on the design of these locomotives, two other, albeit somewhat heavier, classes supplied by other manufacturers, the 4-6-2T by Hawthorn Leslie (SAR class NG 3) , also introduced in 1907, and the SAR class NG 4 with the same wheel arrangement, introduced in 1911 . Cylinder dimensions, drive wheel diameter, boiler pressure and thus also the calculated pulling force were the same for all three types.
literature
- Leith Paxton, David Bourne: Locomotives of the South African Railways. A Concise Guide. C. Strui (Pty) Ltd., Cape Town 1985, ISBN 0-86977-211-2 .
