Paxman Valenta

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]

  1. ^ a b c d e f g 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 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.