SECR K and SR K1 classes
SECR K & SR K1 (River) classes Southern Railway | |
---|---|
Class | K and K1 classes |
Numbers | K: 790–809 K1: 890 |
Official name | River class |
Nicknames | Rolling Rivers |
Withdrawn | 1927 |
Disposition | All rebuilt to U or U1 class — One rebuild surviving |
The SECR K class was a type of
The K class was designed to be mechanically similar to the
Twenty-one locomotives were built: twenty K class (two cylinders) and one K1 class (three cylinders), the first in 1917 and the remainder between 1925 and 1926. They operated over the
Background
Three factors dictated the type of locomotive that could operate on the
Richard Maunsell was appointed CME of the SECR in 1913, following the enforced retirement of
Design and construction
The 2-6-4 wheel arrangement was not in common use in Great Britain at this time, as many railway companies operated routes that required locomotives with greater fuel capacity, or short branch lines that necessitated smaller locomotives. The 2-6-4 tank engine design had only been used once before for
The K class design used a "
The K class was designed by Maunsell's team in 1914 as part of his proposed standardisation programme following the N class,[10] but the designs were not shown to the railway directors until early 1915 to enable all six designs to be shown at once.[8] The design incorporated the principles of power and reliability established by George Churchward, using a Belpaire firebox that sloped downwards towards the cab instead of a round-topped version, a regulator located in the smokebox, long-travel valves for free running at high speeds, a sharply tapered and domeless boiler, and a right-hand driving position.[9][10] The inclusion of these features is attributed to Holcroft, Maunsell's personal assistant, who had worked on the GWR 4300 class and the N class.[12] James Clayton, Maunsell's Chief Locomotive Draughtsman, brought simpler and more functional Midland Railway influences to the design, such as the shape of the cab and the drumhead-type smokebox, which sat on a saddle that was of wider diameter than the fully lagged and clad boiler.[13] The latter was fitted with Ross pop safety valves and pressed to 200 psi (1.38 MPa).[13]
Other innovations by Maunsell's team included greater
K class
In January 1915 Maunsell received authority to build six examples, but, as with the N class, production was delayed due to the use of the Ashford works for wartime armaments manufacture. Assembly began in 1917 and the first, No. 790, emerged in July of that year.[15] It was based at Bricklayers Arms depot,[16] preceding the earlier N class design into service by one month.[15] Further construction was deferred until after Ashford had caught up with the maintenance backlog caused by the war.
Ten more locomotives were ordered by the SECR from Ashford works in June 1920, and to speed delivery the construction of
Maunsell was appointed CME of the newly formed Southern Railway in 1923, and inherited the 1920 SECR order for ten K class locomotives. The order was still outstanding in 1924, although most of the component parts had been made. On 14 January 1925, Maunsell ordered No. 790 to be overhauled and trialled on the
In May 1925 Maunsell ordered a further ten locomotives from Brighton works (Nos. A800–A809), which only had vacuum brakes for the SECR stock on the Eastern section.[18] They were delivered between July and December 1926. This group had modified suspension on the bogie and leading axle, in an attempt to address complaints from the crews of rough riding experienced with earlier members of the class.[17] A further 20 members of the class were ordered in March 1926 (ten each from Ashford and Brighton works), despite strong reservations expressed by the Operating Department concerning "the wisdom or desirability of placing so many large passenger tanks in service".[21] These were allocated the numbers A610–A629, and work had begun on building the frames and cylinders when the order was cancelled following an accident at Sevenoaks in 1927 involving locomotive No. A800.[21] These numbers were later allocated to the first production batch of U class locomotives.
K1 class
In August 1919, a proposal was put to the SECR's Locomotive, Carriage and Wagon Committee for 2 and 3-cylinder tank engines of 2-8-0 wheel arrangement for heavy shunting of freight wagons.[22] They were to use the same boiler as the K and N classes and the general layout was similar to designs used by the GWR in South Wales.[22] Nothing came of this proposal because of other commitments and the absorption of the SECR into the Southern Railway.[22] In 1922, Holcroft suggested that 3-cylinder 2-6-0 tender locomotives with 6 ft (1,830 mm) driving wheels should be built instead of tank locomotives.[23] Despite the benefit of a greater operational range, Holcroft's immediate superior, Clayton, refused to pass this suggestion on to Maunsell.[23] The 3-cylinder principle was therefore applied to the K class.[23]
At the Southern Railway's January 1925 Locomotive Committee meeting, when it was decided to use outside contractors to build the K class, Maunsell received authority to retain one set of parts at Ashford works to construct a prototype 3-cylinder 2-6-4 tank. The modification was based upon that used on N class No. 822 to produce a 3-cylinder locomotive in 1922, although it retained the 6 ft (1,830 mm) driving wheels and shorter wheelbase of the K class.
The main visual difference between the K and K1 classes was at the front end: the K1 incorporated a vertical metal cover above the front buffer beam to protect the third cylinder and associated Holcroft valve gear assembly from the elements.[1] It also featured a new cab design with redesigned single front spectacle plates, and a pair of substantially constructed steps were fitted behind both outside cylinders to provide access to the running plate.[25] The lack of a middle cylinder on the K class locomotives had allowed the provision of a footplate that curved from the buffers to the water tanks. The K1 prototype emerged from Ashford works as No. A890, and underwent trials from 1 December 1925 before entering regular service.[26] Only one locomotive of the K1 class was built; plans to build a further ten (Nos. A891-A900) alongside a batch of five N1 class 2-6-0s were cancelled after the Sevenoaks accident in August 1927.[27] Following rebuilding as a 2-6-0 tender locomotive in 1928, No. A890 was reclassified U1 and was the forerunner of twenty more basically similar locomotives built in 1931.[28]
K and K1 class construction history
Year | Batch[12][25] | Quantity | SECR/SR numbers | Class |
---|---|---|---|---|
1917 | Ashford Works ) |
1 |
790 | K
|
1925 | ) |
9 |
A791–A799 | K
|
1925 | Ashford Works ) |
1 |
A890 | K1
|
1926 | Brighton Works ) |
10 |
A800–A809 | K
|
Naming the locomotives
The K class prototype operated without a name until 1925, when the Southern Railway's publicity department decided to name all express passenger locomotives. The locomotives constructed from 1925 were named after rivers found within the Southern Railway's operating area, and the class became known collectively as the River class.[29] The first-completed Southern Railway K class No. A791 was named River Adur whilst the former SECR prototype was given the name River Avon; names were also allocated to the cancelled 1926 batch of locomotives.[30] The K1 class locomotive No. A890 was named River Frome.[30] The names were displayed on a rectangular brass nameplate fitted to the water tank sides.[11]
Operational details
The K class was intended to haul the SECR's Kent expresses, and was trialled between Charing Cross,
The Southern Railway's motive power re-organisation following
Performance of the tank locomotives
The K class proved successful on well-maintained track.[5] It was capable of high speeds on express passenger duties, although their use was limited by the lower storage capacity of tank locomotives, which meant the K and K1 classes were prone to water shortages on the long Kent Coast routes, and precluded them from working many of the former London and South Western Railway (LSWR) routes west of London.[32] The need to save weight meant that compromises were made in some aspects of the design. The boiler size was constrained by the SECR's axle-loading restrictions, with the result that the design's full steaming potential was not realised.[13] The failure to capitalise upon a larger boiler would also affect Maunsell's subsequent 2-6-0 classes, as they were given the same boiler despite their lower axle-loadings.[13]
On the Southern Railway's Central and Eastern sections, crews complained that the locomotives rolled heavily and unpredictably on the cheaply laid track of the former SECR and LBSCR networks, leading to their nickname, "Rolling Rivers".[5] The rolling was in part caused by the type of coil suspension and steadying springs used on the Bissel truck and bogie axles, which caused adverse springing on poor track.[33] These were modified in later batches, with limited success.[34] The rough-riding was also attributed to the frames, which were of insubstantial construction to save weight.[13] The bracing proved incapable of counteracting the stresses applied to the frames when travelling at speed and caused excessive vibration on the footplate at higher outputs.[13]
The K1 prototype was slightly faster and more powerful than the K class, and gave a smoother ride at low speeds.[35] It was also found to have a wider route availability due to the smaller outside cylinders.[35] However, the Holcroft valve gear proved to be difficult to maintain in everyday service. This locomotive was also noted for particularly poor riding characteristics at high speed, derailing twice in 1927.[32] The first derailment occurred at Borough Green & Wrotham, near Maidstone on 31 March, when the flanges of the lead coupled wheel mounted the rails at 60 mph (97 km/h).[34] The second derailment was at Bearsted on 20 August, when the lead driving wheel mounted and completely dropped off the rails at 40 mph (64 km/h), derailing the train and causing serious damage to the track.[34] These derailments were attributed to the slightly higher centre of gravity of the boiler on the K1.[20] Although the official reports of these accidents blamed the poor quality of the track, a group of directors sought to have both classes banned from use on passenger services, but were overruled by the Southern Railway's Chairman of the Board of Directors, Everard Baring on grounds of cost.[28]
Accidents and incidents
- In March 1927, locomotive No. 890 River Frome was hauling a train which derailed at Wrotham, Kent.[36]
- On 2 August 1927, Locomotive No. 800 River Cray was derailed at Maidstone, Kent.[37]
- On 20 August 1927, locomotive No. 890 River Frome was hauling a passenger train which was derailed at Bearsted, Kent. The cause was attributed to track defects.[38] The locomotive was repaired and re-entered service on 23 August. It was involved in a serious accident the next day.[36]
Sevenoaks disaster
The K and K1 classes suffered from stability problems when travelling at speed over points and curves.
In the days following the accident, two K and K1 class engines were trialled on the
The 1928 accident inquiry did not attach blame to the Southern Railway for track maintenance or locomotive performance issues, and noted that the prototype had run for eight years over the same stretch of line without complaint.[43] However, it identified the Brighton batch and No. A890 as being more susceptible to rolling on sharp curves with weak rail joints, although the entire class operated without incident on the former LBSCR network.[44] The management of the Southern Railway realised that to have any success in operating the K class tanks on other parts of the network, vast stretches of track would require upgrading.[20] With the prospect of storing 20 locomotives whilst the necessary upgrading took place, the management recommended the class be fully withdrawn from service.[1] To recoup the expense of constructing the engines, Maunsell was given permission to rebuild them to the new SR U class 2-6-0 tender engine design in 1928.[3] This decision also reduced the adverse publicity generated by the accident.[3] However, many of the components discarded during the rebuilding process would later be re-used on another 2-6-4 tank locomotive designed to haul heavy freight on short trips: the 3-cylinder W class of 1932.[45]
Rebuilding
The rebuilding of the class as tender locomotives was cheaper than relaying track, particularly as in most respects the class had performed well. Rebuilding took place at
Performance of the rebuilt locomotives and withdrawal
As members of the U and U1 classes, rebuilds were used mainly on
Withdrawals took place between 1962 and 1966, by which time many of the rebuilds were based at
Livery and numbering
SECR and Southern Railway
The K class prototype was painted in an unlined
The class prototype was initially numbered 790, with the rest following consecutively with a prefix "A" to denote a locomotive designed for the former SECR.[12] The system of prefixes had been adopted by the SR to distinguish between locomotives with identical numbers acquired from different companies, and the K1 class became No. A890 when built in 1925.[52] This system was replaced from 1928 by a renumbering of all locomotives into one sequence, in which the K class rebuilds became Nos. 1790–1809,[50] and the K1 class rebuild became No. 1890.[55]
Rebuilds in British Railways service
The K and K1 classes were absorbed by
Operational assessment and preservation
Sir Nigel Gresley's independent report on the K and K1 classes during the mainline stability trials stated that they were well designed, mechanically reliable and capable of hauling expresses at high speeds on well-maintained track, which meant that they could have been useful additions to the Southern Railway's suburban commuter fleet.[58] However, they were undoubtedly prone to rough riding and instability, and not only on the poorest quality tracks.[20] The restricted water capacity also limited their use outside the Southern Railway's Central section. The impending electrification of the Brighton Main Line, scheduled for 1932 also meant that fewer duties suitable for heavy passenger tank locomotives would be available in the 1930s. The lack of a suitable role for both classes was considered when the decision was made to rebuild them as U/U1 tender engines following the Sevenoaks disaster.[20] In rebuilt form they continued to operate until the 1960s, and were capable of attaining speeds in excess of 70 mph (110 km/h) with a greater degree of stability.[32]
One K class rebuild has survived: No. A806 River Torridge – converted to U class No. 1806 – was rescued from Woodham Brothers scrap yard in Barry, Vale of Glamorgan, South Wales in October 1976 for use on the Watercress Line.[59] It was restored to ex-British Railways condition as No. 31806.[60] In August 2014, the locomotive entered service with the Swanage Railway.[61]
See also
References
Notes
- ^ a b c d e f Clarke (February 2008), p. 40
- ^ a b Casserley (1966), p. 436
- ^ a b c Scott-Morgan (2002), p. 18
- ^ a b c Whitehouse & Thomas (2002), p. 49
- ^ a b c d e f Clarke (February 2008), p. 38
- ^ a b Whitehouse & Thomas (2002), p. 50
- ^ Whitehouse & Thomas (2002), p. 51
- ^ a b c d Bradley (1980), pp. 66–67
- ^ a b c Bradley (1961), p. 52
- ^ a b c d Middlemass (1990), pp. 148–154
- ^ a b c d e f g h i Bradley (1961), p. 53
- ^ a b c d e Haresnape (1983), pp. 34–36
- ^ a b c d e f g Rowledge (1976), p. 8
- ^ Rowledge (1976), p. 10
- ^ a b c Railway Engineer (1923), pp. 140–143
- ^ Bradley (1980), p. 69
- ^ a b Bradley (1980), p. 70
- ^ a b Holcroft (1965), pp. 145–147
- ^ Bradley (1980), p. 116
- ^ a b c d e f g h i j k l m Bradley (1961), p. 54
- ^ a b Bradley (1980), p. 71
- ^ a b c Rowledge (1976), p. 7
- ^ a b c d e Holcroft (1965), p. 147
- ^ Rowledge (1976), p. 11
- ^ a b Haresnape (1983), p. 66
- ^ Reynolds (1943), pp. 155–156
- ^ Rowledge (1976), p. 22
- ^ a b Bradley (1980), p. 117
- ^ a b Burridge (1975), p. 48
- ^ a b Burridge (1975), p. 49
- ^ Rowledge (1976), p. 25
- ^ a b c Clarke (March 2008), p. 55
- ^ Rowledge (1976), p. 48
- ^ a b c Rowledge (1976), p. 49
- ^ a b Boocock (2010), p. 87
- ^ a b Earnshaw 1989, p. 22.
- ^ Gerard & Hamilton 1981, p. 41.
- ^ Gerard & Hamilton 1981, p. 42.
- ^ Railways Archive (2004) Ministry of Transport, Railway Accidents, (PDF copy of the original inquiry report for the Sevenoaks Railway Accident), Retrieved 6 January 2010
- ^ Bradley (1980), p. 72
- ^ a b c Holcroft (1965), p. 145
- ^ Pringle (1928), p. 28
- ^ Pringle (1928), p. 17
- ^ Pringle (1928), p. 19
- ^ Rowledge (1976), p. 43
- ^ Scott-Morgan (2002), p. 46
- ^ Rowledge (1976), p. 39
- ^ Clarke (March 2008), p. 56
- ^ a b c Herring, Section "U Class", pp. 120–121
- ^ a b c Haresnape (1983), p. 92
- ^ Ian Allan ABC (1966), section: "U class"
- ^ a b c Swift (2006), p. 50
- ^ Haresnape (1983), p. 88
- ^ a b Bradley (1961), p. 63
- ^ Haresnape (1983), p. 93
- ^ a b Ian Allan ABC (1958), section: "U class"
- ^ a b Longworth: Section "U class"
- ^ Pringle (1928), p. 26
- ^ Great Western Society (2000) Saved from Barry – SR locomotives., Retrieved 21 June 2009
- ^ Langston (2008), p. 112
- ^ Wright, Andrew P. M. (24 June 2014). "Swanage Railway strengthens its fleet with three classic 1920s Southern steam locomotives". Swanage Railway. Retrieved 5 May 2016.
Bibliography
- Boocock, Colin (2010). Locomotive Compendium: Southern Railway. Hersham: Ian Allan Publishing. ISBN 978-0-7110-3423-5.
- Bradley, D.L. (1961). Locomotives of the South Eastern and Chatham Railway 1st edition. London: Railway Travel and Correspondence Society.
- Bradley, D.L. (1980). Locomotives of the South Eastern and Chatham Railway 2nd edition. London: Railway Travel and Correspondence Society.
- Burridge, Frank (1975). Nameplates of the Big Four. Oxford: Oxford Publishing Company. ISBN 0-902888-43-9.
- Casserley, H.C.: 'End of the Maunsell moguls—the Southern maids-of-all-work' (Railway World: 1966, 27), pp. 436–440)
- Clarke, Jeremy: 'The locomotives of R.E.L. Maunsell, Part 3: The 'Mogul' family – SECR' (Steam World, 2008 (248)), pp. 38–41
- Clarke, Jeremy: 'The locomotives of R.E.L. Maunsell, Part 4: The 'Mogul' family – SR' (Steam World, 2008 (249)), pp. 54–57
- Earnshaw, Alan (1989). Trains in Trouble: Vol. 5. Penryn: Atlantic Books. ISBN 0-906899-35-4.
- Gerard, Malcolm; Hamilton, J. A. B. (1981) [1967]. Trains to Nowhere. London: George Allen & Unwin. ISBN 0-04-385084-7.
- Haresnape, Brian (1977). Maunsell Locomotives – a pictorial history. Hinckley: Ian Allan. ISBN 0-7110-0743-8.
- Herring, Peter (2000). Classic British Steam Locomotives. London: Abbeydale Press. ISBN 1-86147-057-6.
- Holcroft, Harold (1965). Locomotive Adventure: Fifty Years With Steam 3rd edition. London: Ian Allan.
- Ian Allan ABC of British Railways Locomotives. London: Ian Allan. 1958–1959.
- Ian Allan ABC of British Railways Locomotives. London: Ian Allan. 1966–1967.
- Langston, Keith (2008). British Steam Preserved: Illustrated Comprehensive Listing of Ex-British Railways Steam Locomotives. Horncastle: Morton's Media Group Ltd.
- Longworth, Hugh (2005). British Railway Steam Locomotives: 1948–1968. Oxford: Oxford Publishing Company. ISBN 0-86093-593-0.
- Middlemass, Tom: 'The "Woolworths" — Woolwich Arsenal's tentative entry into main line locomotive building' (Backtrack, 1990 (4)), pp. 148–54
- Pringle, Col. Sir John W. (1928). Railway Accidents: Report on the Derailment of a Passenger Train which occurred on 24 August 1927, near Sevenoaks, on the Southern Railway. London: HMSO.
- Reynolds, W.J.: 'The Maunsell moguls' (S.R. Railway Magazine, 1943, 89), pp. 155–156
- Rowledge, Peter (1976). Maunsell Moguls. Blandford Forum: The Oakwood Press.
- Scott-Morgan, John (2002). Maunsell Locomotives. Hinckley: Ian Allan Publishing. ISBN 0-7110-2872-9.
- Swift, Peter (2006). Maunsell 4-6-0 King Arthur Class: Locomotives in Detail volume 4. Hinckley: Ian Allan Publishing. ISBN 0-7110-3086-3.
- Whitehouse, Thomas, Patrick & David St. John (2002). SR 150: A Century and a Half of the Southern Railway. Newton Abbot: David and Charles.
Further reading
- Fryer, Charles: Railway Monographs No.1: The Rolling Rivers (Sheffield: Platform 5 Publishing, 1993) ISBN 1-872524-39-7
- Grayer, Jeffery: "Scuppering the "U-Boats"" in Robertson, Kevin: The Southern Way Issue No.7 (Corhampton: Noodle Books (July 2009)), pp. 60–65. ISBN 978-1-906419-17-2.
- Nock, O.S.: Great Locomotives of the Southern Railway (Guild Publishing/Book Club Associates, 1987) pp. 98–102,115,132–137,154–160. CN 5587
- Robertson, Kevin, ed.: "Scuppering the "U-Boats" – Years Earlier" (The Southern Way Issue No. 7: Corhampton, Noodle Books (July 2009)), pp. 66–67. ISBN 978-1-906419-17-2.
External links
- The Railways Archive: Accident at Sevenoaks on 24 August 1927
- Southern e-group page: Maunsell K/K1 class 2-6-4T