The New Zealand DF class locomotive of 1954 was the first class of mainline diesel-electric locomotives built for New Zealand's national railway network,[1] built by English Electric. It should not be confused with General Motors Electro-Motive Division DF class of 1979.

New Zealand DF class (English Electric)
English Electric DF 1501 on display outside Sims-PMI in Otahuhu, Auckland. The locomotive has since moved to the Diesel Traction Group, Ferrymead Historic Park.
Type and origin
Power typeDiesel-electric
BuilderEnglish Electric, United Kingdom
Build date1954
Specifications
Configuration:
 • AAR2C-C2
 • UIC(2Co)(Co2)
 • Commonwealth2Co-Co2
Gauge3 ft 6 in (1,067 mm)
Wheel diameter3 ft 1 in (0.940 m)
Minimum curve297 ft (90.526 m)
Wheelbase52 ft 0 in (15.850 m) total, 12 ft 0 in (3.658 m) rigid
Length58 ft 0 in (17.678 m) over headstocks
Width8 ft 4 in (2.540 m)
Height11 ft 6 in (3.505 m)
Axle load11+34 long tons (11.9 t; 13.2 short tons)
Adhesive weight69 long tons (70 t)
Loco weight105 long tons (107 t; 118 short tons)
Fuel typeDiesel
Fuel capacity600 imp gal (2,700 L)
Prime moverEnglish Electric 12SVT Mk 2
RPM range750 - 850 rpm
Engine typefour stroke, four valves per cylinder
AspirationTurbocharged
GeneratorEnglish Electric 828A
Traction motorsSix English Electric 525/2A
Cylinders12 vee
Cylinder size10 in × 12 in (254 mm × 305 mm)
MU working110V, 10 notch electro-magnetic control
Loco brakeair, dynamic
Train brakesair
Performance figures
Maximum speed60 mph (97 km/h)
Power output1,500 hp (1,100 kW) gross, 1,370 hp (1,020 kW) net
Tractive effort38,500 lbf (171.3 kN) at 25% adhesion starting, 27,700 lbf (123.2 kN) at 16 mph (30 km/h) continuous
Career
Number in class10
Numbers1500 - 1509 (1954 to 1965)
1300 - 1309 (1965 to 1975)
LocaleNorth Island
First runJuly 1954
Last run21 June 1975
Disposition9 scrapped
1 preserved

Introduction

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They had a wheel arrangement of (2Co)(Co2) under the UIC classification system, generated 1120 kW (1500 hp) of power, and could achieve a maximum speed of 97 km/h. They started the process of displacing steam motive power from main lines in New Zealand, but were soon displaced themselves by the DA class of 1955.

Initially, 31 DF locomotives were ordered, but this order was amended to ten DFs and 42 DG class locomotives,[2] which in appearance was essentially half a DF but with a similar bulldog nose cab design. The DF locomotives were heavier than the latter and slightly less powerful DAs and were used to haul freight trains on the North Auckland and East Coast Main Trunk lines in Northland and the Bay of Plenty from which the DAs were prohibited by dint of the higher axle loading of the DA class. Their axle loading was 12.2 tonnes (12.0 long tons; 13.4 short tons).[3]

The DF class were confined to the North Island, although they did all visit Dunedin for overhaul at Hillside Workshops. The locomotives did not run in service during their journeys to and from Hillside, instead, they were towed. They were allowed to move under their own power once there and haul transfer freight trains to and from Port Chalmers and Mosgiel as part of tests before returning to service.

On the arrival of the Phase III DA class locomotives in 1964, the DF class was renumbered from the 1500 series to the 1300 series in November 1965 in order to free up the 1500-series numbers for the new DA locomotives.[4]

Withdrawal

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The DFs were unreliable and needed frequent repairs.[5] This contributed to their short lifespan; withdrawal began in 1972 and the last, DF 1301, was withdrawn in June 1975. A plan to shift the whole fleet to the South Island to join their smaller but more versatile DG siblings was proposed. They were to operate on the hilly Dunedin to Oamaru section of the Main South Line but a new locomotive type was chosen in the DJ class.

Preserved locomotive

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DF 1301, the first locomotive built, was donated to the National Federation of Rail Societies NZ (now Federation of Rail Organisations of New Zealand) in 1975. It was placed on static display at Sim Pacific Metals Limited in Auckland, replacing K 900. As part of this it was renumbered to its original number of 1501, but with V-shaped nose stripes in place of the original wing-shaped ones. Initially displayed in the open, a limited shelter was built over the locomotive at a later date although this did not halt the progressive deterioration of the locomotive. Various proposals were put forward for the restoration of the locomotive, but did not amount to anything.

In 2007, with Sims Pacific requiring the area where the DF was located for redevelopment, owners Federation of Rail Organisations of New Zealand concluded an agreement with the Diesel Traction Group (DTG) to have the locomotive moved to their premises for restoration. The first stage of this relocation took place in August 2008 when 1501 was re-railed and then was towed to Westfield Depot for assessment. In January 2009, members of the Group accompanied the locomotive on a three-day 1,100 km trip to Christchurch, from where it moved to their Ferrymead Railway base a few days later.

Following the completion of DI 1102 in late 2018, 1501 is now currently undergoing a restoration to mainline condition by the members of the DTG.

References

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Citations

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  1. ^ "New Zealand Railways Rolling Stock Lists - Class DF (1954)".
  2. ^ "The DG class". New Zealand Railfan. 5 (4). Triple M Productions.
  3. ^ McClare (1980), p. 14.
  4. ^ "Df class of 1954". English Electric Railway Traction in New Zealand. Retrieved 14 April 2017.
  5. ^ Palmer & Stewart 1965, p. 152.

Bibliography

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