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Paxman Valenta

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Paxman Valenta
Paxman Valenta V12 power unit with turbocharger and Brush Traction alternator fitted
Overview
ManufacturerPaxman
DesignerRoy Dingle, Morriss Clover, Arthur Hammond, Ray Roxby[1]
Also calledY3J and RP200[1]
Production1972 (1972)–????[2]
Layout
ConfigurationI6, 60° V8, 60° V12, 60° V16, 60° V18[1][3]
DisplacementI6: 39.48 litres (2,410 cu in)
V8: 52.64 litres (3,210 cu in)
V12: 78.96 litres (4,820 cu in)
V16: 105.28 litres (6,420 cu in)
V18: 118.44 litres (7,230 cu in)
Cylinder bore197 millimetres (7.756 in)[3]
Piston stroke216 millimetres (8.504 in)[3]
Cylinder block materialCast iron
Cylinder head materialCast iron[3]
ValvetrainOHV, 4 per cylinder
Valvetrain drive systemGear-driven
Compression ratio13:1[3]
RPM range
Idle speed600 rpm[3]
Max. engine speed1,640 rpm[3]
Combustion
Operating principlefour-stroke diesel, turbo-charged & intercooled
TurbochargerWater-cooled turbocharger, two on lower-power engines
Fuel systemLucas Bryce unit injector direct injection per cylinder[1]
ManagementRegulateurs Europa 1100 series centrifugal governor, remotely operable[3]
Fuel typediesel, 45 cetane[3]
Oil systemwet sump, SAE30 or 40[3]
Cooling systemWater-cooled[3]
Output
Power outputI6: 1,007 kW (1,350 bhp; 1,369 PS) at 1,600 rpm
V8: 1,492 kW (2,001 bhp; 2,029 PS) at 1,600 rpm
V12: 1,680–2,440 kW; 2,280–3,320 PS (2,250–3,270 bhp) at 1,500-1,640 rpm
V16: 3,250 kW (4,360 bhp; 4,420 PS) at 1,640 rpm
V18: 3,655 kW (4,901 bhp; 4,969 PS) at 1,640 rpm[1][3]
Dimensions
Dry weightV12: 8.12 tonnes (7.99 long tons; 8.95 short tons)
V18: 11.15 tonnes (10.97 long tons; 12.29 short tons)[1]
Chronology
PredecessorPaxman Ventura
SuccessorPaxman VP185

The Paxman Valenta, also known as Y3J and RP200,[1] is a diesel fuelled internal combustion engine formerly made by Paxman in Colchester, England. It was originally developed for, and previously used in the British Rail (BR) Class 43 diesel-electric locomotives, a pair of which powered the InterCity 125 High Speed Train (HST) in a push-pull train set configuration. The Valenta has also been used for electricity generation in diesel generators on offshore oil rig platforms in British waters.[2]

It is still in use in various marine applications today, such as the Upholder / Victoria class submarines, and additionally to provide the electrical power to propel and operate the Royal Navy's Type 23 frigates. The Valenta marine range was available brake powers ranging from 695 to 3,655 kilowatts (940 to 4,970 metric horsepower; 930 to 4,900 brake horsepower) rated to ISO 3046.[3]

History

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Locomotive use

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Class 43 with Paxman Valenta engine at York.

The Paxman Valenta was developed in the early 1970s for British Rail (BR) with the aim of using in both freight and passenger locomotives.[4] The engine was used in 1972 in the two pre-production Class 41,[2] and 197 production Class 43 power-cars that were delivered to power HSTs between 1975 and 1982. In June 1973, the Valenta powered HST prototypes achieved a world speed record for diesel traction engines, reaching 143.2 miles per hour (230.5 kilometres per hour).[2] This world speed record was beaten in 1987 by a Valenta powered production HST, this time reaching 148 miles per hour (238 kilometres per hour).[2]

The engine as originally fitted to the HSTs was designated 12RP200L, and was a V12 four-stroke diesel engine with direct injection unit injectors, turbocharger and air-cooled intercooler. It had a displacement of 78.96 litres (4,820 cubic inches), which developed 2,250 brake horsepower (1,680 kilowatts; 2,280 metric horsepower) at 1,500 revolutions per minute. The design of the Valenta was based on the Ventura which was fitted to the Class 29 diesel locomotives, amongst others. The engine is famous for the 'Valenta Scream' on starting from rest, a distinctive high-pitched whine caused by the engine's turbocharger.[5][6][7] In 1977, the Valenta received the Queen's Awards for Enterprise.[8]

In 1985, four power-cars (43167-43170) were fitted with Mirrlees MB190 engines.[9] Beginning in 1995, a small number were fitted with Paxman VP185 engines, however the majority retained Valentas.[10]

In May 2005, First Great Western had Brush Traction fit two with MTU 16V4000 R41 engines,[11] these V16 units which use common rail fuel injection are ultimately capable of developing 2,720 kilowatts (3,700 metric horsepower; 3,650 brake horsepower), though they are de-rated in the Class 43 HSTs to match the performance of the original Paxman engine.[7] Judged a success, no doubt due to improved fuel economy,[7] as part of a project to extend the lives of the HSTs, First Great Western decided to re-power its entire fleet. Great North Eastern Railway (GNER), CrossCountry, Network Rail, and Grand Central also decided to re-power their fleets with MTUs.[12][13][14] The only operator not to was East Midlands Trains, which opted to replace its Valentas with Paxman VP185s.[15]

Grand Central's 43084 and 43123 were the last two Valenta-engined power-cars in service. They were taken out of traffic on 22 December 2010 for re-powering with the latter named Valenta 1972-2010.

Restoration

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In May 2011, it was announced that the 125 Group would return prototype HST powercar 41001 to service. The power-car was at that time on static display at the National Railway Museum (NRM) in York, England. It received a full overhaul, and was fitted with a reconditioned Paxman Valenta RP200L engine, number S508 installed new into Virgin CrossCountry's 43153 in 2001, before re-installation into First Great Western's 43143 after a spell in storage. It was one of about 10 engines that the 125 Group obtained.[16]

On 15 November 2014, 41001 hauled its first passenger train in preservation.[17]

Australian XPT

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New South Wales XPT, originally powered by Paxman Valenta engines.

The engine was also fitted to the State Rail Authority's New South Wales XPT, or Express Passenger Train, which was based on the HST power car design. Fifteen power car units were built in the 1980s by Commonwealth Engineering, Sydney, supplied with twenty Paxman Valenta engines rated at 2,000 brake horsepower (1,491 kilowatts; 2,028 metric horsepower). This was followed by four additional power cars (using four Paxman supplied Valenta engines) by ABB Transportation, Melbourne in 1994.[2] All were re-powered with VP185s in the early 2000s.[18][19]

Usage

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Inline 6 – 6RP200
V8 – 8RP200
  • BP, a diesel generator gen-set used for primary electricity generation was built by Paxman in 1983, using a V8 Valenta engine. They were used on platforms (gas rigs) in their Morecambe Bay gas production platform off coast of Blackpool in the north-west of England. Following the subsequent commissioning of a gas turbine powered gen-set for primary electricity generation, the Valenta engined gen-set remains for emergency stand-by electricity generation.[2]
V12 – 12RP200
V16 – 16RP200
V18 – 18RP200

References

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  1. ^ a b c d e f g h i j k l m Carr, Richard (28 September 2022). "Paxman Diesel Engines since 1934 – Valenta (also known as the Y3J and the RP200)". PaxmanHistory.org.uk. Richard Carr's Paxman history pages. Retrieved 15 August 2023.
  2. ^ a b c d e f g h i j k l m n o p q r s t u Carr, Richard (31 March 2014). "Valenta and VP185 applications – Valenta (Y3J or RP200) applications". PaxmanHistory.org.uk. Richard Carr's Paxman history pages. Retrieved 16 August 2023.
  3. ^ a b c d e f g h i j k l m Carr, Richard (31 December 2011). "Paxman Valenta (Y3J) technical specification". PaxmanHistory.org.uk. Richard Carr's Paxman history pages. Retrieved 16 August 2023.
  4. ^ "Paxman Valenta will power freight and passenger locomotives". Railway Gazette International: 753. October 1970.
  5. ^ Ford, Roger (1988). HSTs at Work. Ian Allan Publishing.
  6. ^ The Future of the Diesel Engine. Rail Safety & Standards Board.
  7. ^ a b c "Fitting the MTU power unit into the HSTs". RailwayPeople.com. CareerSite.biz Ltd. 15 August 2008. Archived from the original on 15 July 2011. Retrieved 27 February 2010.
  8. ^ "Suppliers". Railway Gazette International: 171. May 1977.
  9. ^ "HSTs to have Mirrlees engines". Railway Gazette International: 899. December 1985.
  10. ^ "Paxman wins order for seven 12VP185 engines". Rail (255): 9. 21 June 1995.
  11. ^ "Life-extended Angel HST rolls out of Brush for £1.5m trial". Rail (514). 25 May 2005.
  12. ^ "Repowering the HST". RailwayPeople.com. CareerSite.biz Ltd. 28 July 2010. Archived from the original on 27 November 2010.
  13. ^ "GNER confirms German built MTU engines for HST fleet rebuild". Rail (544): 12. 19 July 2006.
  14. ^ "Brush wins XC Class 43 HST overhaul deal". Rail (586): 64. 27 February 2008.
  15. ^ "East Midlands Trains goes for VP185s". Today's Railways UK (71): 58. November 2007.
  16. ^ "Preservation Progress". 125group.org.uk. 125 Group. 20 April 2008. Archived from the original on 16 January 2009.
  17. ^ "41001's Restoration & Introduction to Service". 125group.org.uk. 125 Group.
  18. ^ Hollingsworth, Brian; Cook, Arthur (2000). "XPT Eight-car train". Modern Locomotives. p. 180. ISBN 0-86288-351-2.
  19. ^ "Market". Railway Gazette International: 10. April 2000.
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