LSWR S15 class

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LSWR/SR S15 class [1]
LSWR/SR S15 class
Preserved No. 825 at Pickering, October 2005.
Power type Steam
Designer Robert Urie, modified by Richard Maunsell
Builder LSWR/SR Eastleigh Works
Build date 1920–1936
Total production 45
Configuration 4-6-0
UIC classification 2'Ch
Gauge ft 8½ in (1,435 mm)
Leading wheel size 3 ft 7 in (1.092 m)
Driver size 5 ft 7 in (1.702 m)
Length 65 ft 6.75 in (19.98 m)
Locomotive weight Urie: 135 tons 21 cwt (138.1 tonnes) Maunsell: 135 tons 13 cwt (137.7 tonnes)
Fuel type Coal
Fuel capacity 5 tons (5.1 tonnes)
Water capacity 5,000 imp gal (23,000 l)
Boiler pressure Urie locomotives: 185 psi (1.28 MPa); Saturated Boiler: 175 psi (1.21 MPa); Maunsell locomotives: 200 psi (1.38 MPa)
Cylinders Two
Cylinder size 20½ × 28 in (533 × 711 mm)
Valve gear Walschaerts
Tractive effort 29,857 lbf (132.81 kN)
Retired 1962–1966
Disposition Seven preserved, remainder scrapped

The LSWR S15 class is a class of 4-6-0 steam locomotive designed for freight work. They were designed by Robert Urie for the London and South Western Railway (LSWR). After design modifications, several were built by Richard Maunsell for the Southern Railway.

A total of 45 were constructed at Eastleigh Works between 1920 and 1936, and saw service all over the Southern Railway's Western and Central sections. All class members saw service with the Southern Region of British Railways, though all had been withdrawn by 1966. Seven examples of the class have survived into preservation.

Contents

[edit] Background

The LSWR wished to address the requirement for a modern, standardised heavy freight locomotive to work from London's Feltham freight yard to the South-West of England. In this role, a new design was needed to serve the South Coast ports of Portsmouth, Weymouth and Southampton. It was also to convey other forms of traffic, such as milk trains, which required fast transit to the dairies in London.[2] Robert Urie saw the design potential of his LSWR Class H15, and saw this as an opportunity to further develop the 4-6-0 locomotive concept into a purpose-built freight design that was to become the Class S15.[3]

[edit] Construction history

[edit] The first (Urie) batch

The S15 was the third design by Robert Urie for the LSWR. Initiated during the First World War, the design incorporated the lessons learned from the operation of his H15 class, a design that was to provide the basis for future standardization on the LSWR.[4] Due to the constraints of wartime, the class was designed to have interchangeable components with a similar design, the N15 class. [1]

Details such as the boiler, the two-cylinders and valve gear were standardised between both classes, although the principal difference lay in the diameter of the driving wheels.[2] The S15, being primarily a fast freight locomotive, had smaller diameter wheels for the purposes of traction.[1] The first batch was constructed at Nine Elms, with the first of these new freight locomotives entering traffic in February 1920.[2] By May 1921 sixteen were in service, and were mostly allocated to the London area.[4]

Urie retired after the creation of the Southern Railway in 1923. Richard Maunsell, the new Chief Mechanical Engineer, took the decision to revise the cylinder arrangements of the locomotive, and in so doing, delayed the construction of further locomotives until the modifications had been made.[2] In doing this, Maunsell took a sound design, and made it better, achieving a consistent locomotive that could undertake all tasks it was produced for.[4]

[edit] The second and third (Maunsell) batches

Maunsell's modifications entailed the increase of boiler pressure from 180lbf/in2 to 200lbf/in2 and the reduction of cylinder diameter by half an inch.[5] Additionally the footplate was modified, valve travel lengthened, and larger outside steam pipes were fitted to improve flow into the cylinders. Fifteen of the revised design were built at Eastleigh in 1927, and some were allocated six-wheeled tenders for use on the Southern's Central section.[5] This was in order for the locomotive to be turned on the shorter turntables located on this part of the network.[5] From new, the rest of the class was equipped with the Urie 5000 gallon eight-wheel bogied tender, which enabled the class to operate on the extended freight routes of the Southern Railway's Western section.[2] The standardisation of the design was soon evident by the fact that tenders were swapped between other classes on the Southern.[1]

The benefits gained by the modifications showed in the visibly improved performance of the first batch of Maunsell S15s over their Urie built predecessors.[1] A further batch was ordered in 1931, though this coincided with a downturn in the volume of freight due to the economic depression, therefore dictating that the last S15 4-6-0s were not completed until 1936.[1] Around this time, the entire class was equipped with smoke deflectors, a modification that was given to all Maunsell-influenced designs.[2]

Year Order Quantity LSWR / SR numbers Notes
1920
S15
5
497–501
1920
A16
5
502–506
1920
C16
5
507–511
1921
E16
5
496, 512–515
1927
E90
10
823–832
1927
E158
5
833–837
1936
E630
10
838–847

[edit] Livery and numbering

[edit] LSWR and Southern Railway

Preserved No. 828.
Preserved No. 828.

Under LSWR ownership, the S15s were outshopped in the late LSWR dark Holly Green livery, with black and light green lining, which was applied to most freight designs of the LSWR. Gilt lettering and numbering was located on the tender and cabside respectively. [3] The initials 'LSWR' were located on the tender.

The first Southern Railway livery continued that of the LSWR, though with the number displayed on the tender. However, from 1925, a darker Olive-type green was substituted, and the entire class was so outshopped. [3] Wheels were green with black tyres, whilst the cabside numbers were replaced by a cast oval plate with 'Southern Railway' around the edge and the number located in the centre.[5] Primrose Yellow 'Southern' and locomotive number transfers were placed on the tender tank. From 1927, the Maunsell locomotives were outshopped in black livery with green lining, and were to remain in this guise with little modification until Nationalisation.[3]

The only slight livery modification occurred prior to the Second World War, when Oliver Bulleid introduced the 'Sunshine Yellow' lettering and numbering. [3] A further modification was the application of a green shaded 'Sunshine' lettering during the war. This was finally reverted to 'Sunshine Yellow' lettering and numbering after the war. [3] No.823–837 were delivered from Eastleigh during 1927 and 1928 and a further ten, No.838–847 were authorized in 1931.

[edit] Post-1948 (nationalisation)

838 at Salisbury 1949.
838 at Salisbury 1949.

After a period in British Railways transitional livery, the entire class was released in British Railways Freight Black livery with no lining, numbering located on the cabsides and the BR crest on the tender sides. [6] Numbering was initially as per Southern Railway with an 's' prefix, though eventually allocated the British Railways Standard System in the series of 30823–30837 for the second batch, and 30838–30847 for the third.[6]

[edit] Operational details

The Maunsell-modified design provided an excellent goods engine and they were best known for working heavy night express goods trains between Exeter and Nine Elms, Southampton. They were also vary capable passenger engines when used during peak holiday periods.[1] Both the Urie and Maunsell S15s spent most of their working lives on the Southern's Western section.[2] Eventually all the Urie engines were concentrated at the Southern's London freight depot in Feltham.[2] Alongside Feltham the Maunsell S15s were allocated to Exmouth Junction, Hither Green and Salisbury, indicating the 'go anywhere' nature of the class.[1] The S15s outlived the King Arthur class because of their dual freight/passenger abilities. However, they were retired between 1962 and 1966 as part of the British Railways Modernisation Plan.[2] Maunsell S15 number 30837 was the final operational example of the class, returning to Feltham in January 1966 to work a farewell rail tour.[1]

[edit] Preservation

No fewer than seven S15s have been preserved, with two built by the LSWR and five by the Southern Railway:

[edit] References

  1. ^ a b c d e f g h i Herring, Peter, Classic British Steam Locomotives (Abbeydale Press: London, 2000) Section "S15 Class" Pages 100 to 101 ISBN 1861470576
  2. ^ a b c d e f g h i Russell, J. H.: A Pictorial Record of Southern Locomotives (Oxford Publishing Company: Oxford), (no ISBN given)
  3. ^ a b c d e f Swift, Peter: Maunsell 4-6-0 King Arthur Class (Locomotives in Detail series volume 4) (Hinckley: Ian Allan Publishing, 2006), ISBN 0711030863
  4. ^ a b c Bradley, D. L.: LSWR Locomotives - the Urie classes (Wild Swan Publications, 1987), ISBN 090686755X
  5. ^ a b c d Haresnape, Brian: Maunsell Locomotives - a pictorial history (Ian Allan Ltd, 1977), ISBN 0711007438
  6. ^ a b Longworth, Hugh: British Railway Steam Locomotives: 1948–1968 (Oxford Publishing Company: Oxford, 2005) ISBN 0860935930

[edit] Further Reading

  • Allan, Ian: ABC British Railways Locomotives Part 2 - Nos. 10000-39999 (Ian Allan Ltd: 1949)

[edit] External links