SR Lord Nelson class
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 No. 850 Lord Nelson as preserved. |
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| Power type | Steam |
|---|---|
| Designer | Richard Maunsell |
| Builder | SR Eastleigh Works |
| Build date | 1926–1929 |
| Total production | 16 |
| Configuration | 4-6-0 |
| Gauge | 4 ft 8½ in (1,435 mm) |
| Leading wheel size | 3 ft 1 in (0.94 m) |
| Driver size | 6 ft 7 in (2.01 m) |
| Length | 69 ft 9¾ in (21.27 m) |
| Locomotive weight | 142 tons 6 cwt (144.5 tonnes) |
| Fuel type | coal |
| Fuel capacity | 5 tons (5.1 tonnes) |
| Water capacity | 5,000 imp. gal (22,700 litres) |
| Boiler pressure | 220 lbf/in² (1,500 kPa) |
| Fire grate area | 33 ft² (3.07 m²) |
| Cylinders | 4 |
| Cylinder size | 16½ in × 26 in (41.9 cm × 66 cm) |
| Tractive effort | 33,500 lbf (149 kN) |
| Career | Southern Railway (Great Britain), Southern Region of British Railways |
| Class | 7P |
| Locale | Great Britain |
The SR class LN or Lord Nelson class is a class of 4-6-0 steam locomotive designed for the Southern Railway by Richard Maunsell. Intended for express passenger work to the South-West of England. 16 of them were constructed and represented the ultimate in Southern 4-6-0 design. They followed Southern Railway practice of naming their express passenger types, in this case after famous admirals.
The class continued to operated with British Railways until 1961, after modifications were made to the blastpipe by Oliver Bulleid. The class was withdrawn in 1961, and only one example of the class has been saved from scrapping. Lord Nelson can be seen running on mainline tours throughout Britain.
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[edit] Background
The requirement to secure a more modern and powerful replacement for the N15 Class led to Maunsell considering a larger 4-6-0 design with a larger boiler and firebox.[2] The new design was intended for heavy express passenger work in South-West England, 16 locomotives were constructed and proved to be the ultimate in 4-6-0 steam locomotive design on the Southern Railway.[2]
[edit] Construction history
Production began in 1926 at Eastleigh when the prototype, Lord Nelson was constructed. The locomotives were nominally an improvement on Robert Urie's N15 King Arthur class, being able to pull heavier loads at sustained speeds of 55 mph. Maunsell developed the prototype over two years, with production beginning in 1928, and ending in 1929 with the 16th class member.[1] The heavy loads envisaged for this class failed to materialise, with subsequent economic consideration ending the production run.[3]
An unusual, and extremely rare feature of the Lord Nelson class of locomotives was the setting of the crank axles at 135°, rather than the 90° of other locomotive types, which was designed to give a far more even pull on the fire. This in turn gives eight beats per revolution, rather than the standard four of other locomotives.
Due to the long distance running expected of the class, locomotives working on the Western section of the Southern Railway were provided with a modified "watercart" design of bogied tender, with high coal and water capacity. Locomotives allocated to the Eastern section were provided with smaller, six-wheeled tenders. Other features were in common with the King Arthur class, the boiler being the same length, as well as the use of a Belpaire firebox.[3]
[edit] Modifications
The class gained a reputation of being poor steamers, prompting Oliver Bulleid, Maunsell's replacement as CME of the Southern, to modify the Lord Nelsons in 1938. The modifications consisted of larger diameter chimneys and Lemaître multiple jet blastpipes, which effectively transformed their performance.[1]
[edit] Naming the locomotives
The locomotives were named after famous Royal Navy admirals, with the doyen of the class being named Lord Nelson. As a result, the rest of the locomotives belonged to the 'Lord Nelson' (LN) class.[4]
[edit] Operational details
For a period upon introduction to the Southern Railway network, the Lord Nelson class held the title of "most powerful locomotive in Britain" a claim based upon the tractive effort.[5] The advanced design of the locomotive led to the GWR introducing the GWR 6000 Class in order to regain the title lost by their GWR Castle class locomotives when the Lord Nelsons were constructed.[1] One was involved in what could have been a major accident during 23 January 1930. This entailed the leading driving wheels jumping off the track, though the locomotive ran for many yards before they re-railed themselves over a point without the crew's knowledge.[6]
The Lord Nelsons were notoriously difficult for inexperienced crews to fire properly due to their long firebox.[2] To circumvent such problems, specific crews who had proven experience in firing the locomotives were allocated.[2] The cause of this problem was that there were relatively few locomotives in the class for crews to train on.[5] However, they were highly respected, and were a good deputy for the Bulleid Pacifics, which superseded them on top link expresses.[5] Another point of interest lies in the fact that the LMS Royal Scot Class was loosely based on this design.[7]
The Lord Nelson class locomotives frequently deputised for stricken Bulleid pacifics throughout the 1950s.[3] They remained in the Top Link until the rebuilding and subsequent increased reliability of the Bulleid pacifics rendered the Lord Nelsons superfluous to operational requirements and were gradually phased out of service.[2] This meant that all Lord Nelson class locomotives had been withdrawn by 1962.[1]
[edit] Preservation
The only survivor, the class doyen (30)850 Lord Nelson has been preserved as part of the National Collection, and is now running on the national network.
[edit] Livery and numbering
[edit] Southern Railway
Livery was Southern Railway Malachite Green with "Sunshine Yellow" lining on the boiler rings. During the war years, the locomotives were outshopped in Wartime Black livery, though retained the word "Southern" in yellow on the tender.[2]
Numbers allocated to the locomotives were a variation of LSWR practice, and being constructed at Eastleigh were given the prefix 'E' before the number to distinguish from the locomotives of other pre-grouping railway companies that also carried the same number.[2] In the case of the Lord Nelson class, the numbering ranged from E850–E865. This was eventually superseded by numbers without the 'E' prefix, becoming 850 to 865 from 1931.[8]
[edit] Post-1948 (nationalisation)
The initial livery applied following the nationalisation of the railways in 1948 was modified Southern Malachite Green and "Sunshine Yellow" with "British Railways" on the tender, and the Southern numbering system was temporarily retained with an "S" prefix (such as S850) until superseded by the British Railways numbering system.[2] The locomotives then carried British Railways Brunswick Green livery with orange and black lining.[2] By this stage, the locomotives were renumbered under standard British Railways procedure, from 30850–30865.[9]
[edit] See also
[edit] References
- ^ a b c d e Herring, Peter: Classic British Steam Locomotives (Abbeydale Press: London, 2000) Section "King Arthur & Lord Nelson Classes" ISBN 1861470576 Pages 110-111
- ^ a b c d e f g h i Swift, Peter: Maunsell 4-6-0 Lord Nelson Class (Locomotives in Detail series volume 9) (Hinckley: Ian Allan Publishing, 2007), ISBN 0711032475
- ^ a b c Haresnape, Brian: Maunsell Locomotives - a pictorial history (Ian Allan Ltd, 1977), ISBN 0711007438
- ^ Burridge, Frank: Nameplates of the Big Four (Oxford Publishing Company: Oxford, 1975) ISBN 0902888439
- ^ a b c Whitehouse, Patrick & Thomas, David St.John: SR 150: A Century and a Half of the Southern Railway (Newton Abbot: David and Charles, 2002) ISBN 0715313762
- ^ Anderson, E.P.: 'Report on the partial derailment of the engine of an express passenger train that occurred on the 23rd January, near Kent House', Ministry of Transport: Railway accidents ... which occurred during the three months ending 31st March, 1930 (London: HMSO, 1930)
- ^ Southern E-Group (2004)[1], Retrieved May. 3, 2007. For information on influence.
- ^ Maunsell Society Newsletter (1980)[2] Retrieved May. 16, 2007. For information on the 'E' numbering system.
- ^ Ian Allan ABC of British Railways Locomotives, winter 1958–59 edition
[edit] External links
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