New South Wales 620/720 class railcar

The 620/720 class railcars were a class of diesel multiple unit built by the New South Wales Government Railways and operated from 1961 until 2007.

620/720 class railcars
Interior of a 620/720 carriage
ManufacturerNew South Wales Government Railways
Built atChullora Railway Workshops
Constructed1961–1968
Entered service1961–2007
ScrappedLast revenue service in 2007
Number built36 vehicles (18 two-car units)
Number in service1 (car 726)[1]
Number preserved21
Formation1 power car, 1 driving trailer car
Fleet numbers621/721 - 638/738
OperatorsCityRail
Specifications
Car body constructionAluminium body on steel underframe
Car length18.67 m (61 ft 3 in)
Width2.97 m (9 ft 9 in)
Maximum speed115 km/h (71 mph)
Traction systemDiesel-hydraulic
Prime mover(s)Rolls-Royce C8SFLH, 250 hp / GM Detroit Diesel 6/110, 250 bhp / Cummins NHHRTO-6-B1, 265 hp / Cummins NTA-855-R2, 300 hp / Cummins NTA-855-R4, 335 hp
Power output500 hp (373 kW)
(250 hp (186 kW) x 2);
530 hp (395 kW)
(265 hp (198 kW) x 2);
600 hp (447 kW)
(300 hp (224 kW) x 2);
670 hp (500 kW)
(335 hp (250 kW) x 2)
TransmissionAutomatic lockup torque converter
Power supply24 V DC
Braking system(s)S.E.M. electro-pneumatic straight air with emergency feature, handbrake
Track gauge1,435 mm (4 ft 8+12 in) standard gauge

Construction edit

The 620/720 class railcars were an evolution of the 600/700 railcars that had been built in 1949/50. Like their predecessors they were built with an aluminium body on a steel frame at the New South Wales Government Railways' Chullora Railway Workshops. However they were fitted with different engines, transmissions and electrical systems. Six received two 8-cylinder Rolls-Royce C8SFLH with Rolls-Royce DFR 11500 transmissions, 11 received two 6-cylinder GM Detroit Diesel 6/110 with Allison RC3 transmissions and one received two 6-cylinder Cummins NHHRTO-6-B1 engines with Twin Disc DFFR 10034 transmissions.[2] Electrically, the class was compatible with the 900 Class DEB sets and both classes could work interoperably.

History edit

The first five sets were ordered to operate suburban services out of Newcastle and were fitted with economy class seats throughout. The next six were constructed with both first and economy class accommodation to operate longer services out of Newcastle and between Liverpool and Campbelltown until the latter section was electrified in 1968. The remaining seven were constructed to operate regional services including :

From the mid-1970s, one was attached to the DEB set operating the Canberra Monaro Express during times of heavy demand.[3] In late 1984, two were transferred to Wollongong from Lithgow joining three sets that had been there for many years.[4] The balance of the fleet by this stage was all based in Newcastle.

Withdrawals and Upgrades edit

 
No. 623/723 in its final CityRail livery at the New South Wales Railway Museum, Thirlmere, 31 March 2016.

During the life of the class, three cars were damaged in accidents and withdrawn. NPF 624 was burnt out at Gosford in 1981, NTC 734 was damaged in a collision with a motor vehicle on the Gwabegar line in 1981 and subsequently withdrawn in 1983, while NTC 728 was damaged in a collision with a coal train at Hexham in 2002 and was not repaired. NPF 634 was matched with trailer NTC 724 and they operated as a mismatched set until they were withdrawn.

MPF 638 was fitted with Japanese Niigata DBRG2115 transmissions as a trial in 1978 and proving reasonably successful Niigata transmissions were deployed in some of the 900 Class power cars. Ageing equipment plagued the Class in the 1970s and five units received 300 hp Cummins NTA-855-R2 engines and Twin Disc DFFR 10034 transmissions originally destined for upgrading the 600 Class power cars.

From the early 1980s, the remaining Rolls-Royce and GM powered units, along with Cummins powered NPF 638, were fitted with 335 hp Cummins NTA-855-R4 engines and Voith T211r transmissions. This drive train proved highly successful and was also deployed in the 900 Class power cars.

First eleven withdrawn edit

It was planned that all would be replaced by the 15 Endeavour railcars in 1994 but after it was decided to divert some of these units to Main South line services, seven were retained, all based in Newcastle.[5] These were all overhauled by Rail Services Australia, Chullora in 1999 including a repaint into CityRail livery and fluorescent lights fitted.[6] The seven sets remaining (621/721, 623/723, 625/725, 626/726, 628/728, 629/729 and 631/731) were based at the CityRail Endeavour Service Centre at Broadmeadow. These units, in conjunction with five Endeavour railcar sets provided services on the Hunter Valley network.

Final seven withdrawn edit

Following the delivery of the Hunter railcars all seven were withdrawn in 2007, with a last service running on 29 October 2007, as a special service with invited guests, from Newcastle to The Rail Motor Society's Depot at Paterson and return.[7]

Preservation edit

 
625/725 at Newcastle station

A few have been preserved:

RailCorp converted 631/731 to Mechanised Track Patrol Vehicle ML070 with 625/725 retained as a source of spares from 2009. Track patrols commenced using ML070 in early 2011.[17] Cooma Monaro Railway secured ownership of both in January 2015 and they were stored in the Cooma railway yard precinct. They were sold in 2020 to a private owner in Canberra who restored them to operational status and are currently leased.

The Lithgow State Mine Railway was loaned 623/723 for restoration at Goulburn Railway Workshops, for eventual re-entering of service in Lithgow and the surrounding region.[18] Following a breakdown in negotiations, 623/723 subsequently returned to Transport Heritage NSW at Thirlmere.

References edit

  1. ^ "Byron Bay Train » History". Byron Bay Train. Retrieved 26 November 2019.
  2. ^ Cooke, David (1984). Railmotors and XPTs. Australian Railway Historical Society NSW Division. ISBN 0-909650-23-3.
  3. ^ Stokes, HJW (1984). Railways of the Canberra and Monaro Districts. Canberra: Australian Railway Historical Society, ACT Division. p. 27.
  4. ^ "620 Sets" Railway Digest December 1985 page 355
  5. ^ "Endeavours Enter Service Only Days After Launch" Railway Digest May 1994 page 10
  6. ^ "CityRail 620 Class "Great Survivor" Refurbishment Underway" Railway Digest April 1999 page 9
  7. ^ "Hunter Valley farewells red rattler". News Online. Australian Broadcasting Corporation. 29 October 2007.
  8. ^ NPF 621 - Diesel Power Car Department of Environment & Heritage
  9. ^ NTC 721 - Diesel Power Car Department of Environment & Heritage
  10. ^ "A Tale of Two Monuments" Railway Digest June 2013 page 54
  11. ^ NPF 623 - Diesel Power Car Department of Environment & Heritage
  12. ^ NTC 723 - Diesel Power Car Department of Environment & Heritage
  13. ^ Newsletter No 3 Lithgow State Mine Railway and currently undergoing restoration November 2013
  14. ^ "Tamworth Takes to Tourism Training Train" Railway Digest August 2000 page 43
  15. ^ "Eligible Preservation Groups" Railway Digest December 1998 page 39
  16. ^ Dorrigo Railway Museum Exhibit List 37 Dorrigo Steam Railway & Museum 17 March 2011
  17. ^ 620s are back on track Paterson Points June 2010 page 5
  18. ^ THNSW (12 September 2018). "Lithgow State Mine Railway acquire diesel railmotor". THNSW. Retrieved 18 April 2021.