New Zealand EF class locomotive

The New Zealand EF class locomotive (originally Class 30) is a class of 25 kV 50 Hz AC electric locomotives that operate on the North Island Main Trunk (NIMT) between Palmerston North and Te Rapa in New Zealand. Built by Brush Traction in Loughborough, England between 1986 and 1988 to run on the new electrified central section of the NIMT, at 3,000 kilowatts (4,000 hp), they are the most powerful locomotives to operate in New Zealand. They are the only class of electric locomotives in service in New Zealand.

New Zealand EF class locomotive
30042 on The Overlander at Palmerston North, March 2007.
Type and origin Power type Electric Builder Brush Traction, Loughborough, England Build date 1986 – 1988
Specifications Configuration: ​  • UIC Bo′Bo′Bo′ Gauge 3 ft 6 in (1,067 mm) Length 19.6 metres (64 ft 4 in) Loco weight 107 tonnes (105 long tons; 118 short tons) Electric system/s 25 kV 50 Hz AC catenary Current pickup(s) Pantograph Traction motors 6
Performance figures Maximum speed 105 km/h (65 mph) Power output 3,000 kW (4,000 hp) (continuous)
Career Class EF, previously Class 30 Number in class 22 Numbers 30007 – 30249 Nicknames Toasters Locale North Island Main Trunk between Palmerston North and Te Rapa First run 1988 – 1989 Disposition 12 in service 7 withdrawn 2 scrapped

Background

The NIMT is a 681-kilometre (423 mi) long rail line that links New Zealand's capital Wellington and largest city Auckland, and is one of the major backbones of the country's rail network. The line was completed in 1908 and opened the following year, and included various engineering feats on the central section between Hamilton and Palmerston North, including the Raurimu Spiral and numerous viaducts – five of which are over 70 metres (230 ft) high.

Electrification of the NIMT was first proposed as early as 1918 due to coal shortages during World War I, and later was proposed in the 1950s when diesel locomotives started to replace steam. The section between Wellington and Paekakariki was electrified in 1938 at 1500 V DC to prevent steam build-up in the long Tawa tunnels under the Wellington hills and to provide banking on the steep seaside section from Paekakariki up to Pukerua Bay.[1]This electrification has since been extended further north to Paraparaumu in 1983 and again to Waikanae in 2011.

Following the oil shocks of the 1970s, the National government, led by Prime Minister Robert Muldoon, launched the "Think Big" energy development projects. One of the projects involved the electrification of the 411-kilometre (255 mi) central section of the NIMT between Palmerston North and Te Rapa.[2]This section was chosen for the topography of the line between these two cities, and the advantages electric locomotives had over diesel in this area. The 2,050-kilowatt (2,750 hp) DX class diesel-electric locomotives, then the mainstay of the NIMT and only recently introduced themselves, could handle 720-tonne freight trains on the section, but could only average 27 kilometres per hour (17 mph) when climbing the 1 in 52 gradient of the Raurimu Spiral. A more powerful locomotive however, in this case an electric locomotive, could haul a 900-tonne freight train up the same section of track at a speed of 45 kilometres per hour (28 mph). Electric trains also had advantages during the 1970s oil shocks as New Zealand relied on imported oil to supply its diesel locomotives. Meanwhile, New Zealand's electricity supply is mainly generated from renewable hydroelectricity (hydroelectricity generated 84.5% of New Zealand's electricity in 1980),[3] and therefore electric trains do not have to rely on imported oil to operate.

Service

Introduction

The electrification of the central section began in 1984, with the government setting aside NZ$40 million to purchase a fleet of 25 kV AC locomotives to operate the new electrified line. The contract to build 22 electric locomotives was let to Brush Traction of Loughborough, England.[4] The first two, numbered 30007 and 30013, arrived in 1986 and were used in the testing of the new electrification system, while the remaining 20 locomotives were introduced after the electrification of the NIMT was completed.

The locomotives are able to generate a continuous power output of 3,000 kilowatts (4,000 hp), making the class the most powerful to operate on the New Zealand railway network. They also feature the unusual wheel arrangement of Bo-Bo-Bo, which had been previously used on the EW class and the DJ class. The advantage of using the Bo-Bo-Bo arrangement over the traditional Co-Co arrangement is that it provides greater flexibility for New Zealand's lightly laid and sharply curved tracks, resulting in less wear on the rails.

The locomotives are supplied electricity from 25 kV AC overhead lines. These lines draw electricity from New Zealand's national grid at four locations along the electrified section: Bunnythorpe, Tangiwai, Taumarunui, and Hamilton. The locomotives are fitted with regenerative braking as well as regular air brakes, so the traction motors can be turned into generators when the locomotive is coasting downhill and feed electricity back into the overhead lines and the national grid.

The EF class were nicknamed "Toasters" or "Shoe Boxes" by New Zealand rail enthusiasts due to their boxy shape.[5]

In service

The EF class were first used to haul freight trains along the central section of the NIMT, with the completion of electrification in 1988.[5] Freight trains travelling from Auckland would be diesel-hauled to Te Rapa, change there to an EF locomotive and be hauled to Palmerston North where they would be changed back to a diesel locomotive to continue to Wellington. This remains the practise today, although trains that do not traverse the length of the central section (such as pulp trains from Karioi mill) are entirely diesel-hauled to save switching the locomotives. Similarly, freight trains that are destined for or originate from the Marton - New Plymouth Line are diesel-hauled for 30 km section of the NIMT between Palmerston North and Marton.

The locomotives had a number of teething issues when first introduced. After two years in service, two locomotives were withdrawn due to transformer failures, and converters were found to be unreliable and required replacing. The locomotives also suffered from longitudinal oscillation at low speed and required dampers to be fitted. This work was completed under warranty from Brush,[6] after New Zealand Railways withheld the final payment of $44 million to Brush pending a solution to the locomotives' problems.[7] The locomotives transformer issues continued, and an upgrade program was undertaken over 1993 and 1994 which saw the 20 remaining locomotives receive upgraded transformers and overhauled traction motors. This work was undertaken at the Hutt Workshops with EF 30007 the first to be treated after having been out of action for some time prior.[8]

Prior to the Stratford–Okahukura Line being mothballed usual operating practice was for the services originating from Auckland/Hamilton and Stratford to meet at Taumarunui and exchange trains there, with an EF regularly hauling the Hamilton-Taumarunui-Hamilton legs. With the mothballing of this line most services now run direct between Palmerston North and Te Rapa.

EF 30163 hauling The Overlander near Waiouru on 22 March 2003

EF 30013 on the NIMT in bumble bee livery

Electric-hauled passenger services originated later, due to the then daylight NIMT service, the Silver Fern, utilising diesel-electric rail cars. When the locomotive-hauled Overlander daylight service replaced the Silver Fern in December 1991, EF class locomotives began to be used to haul it across the central section, and later, the locomotives were used on the overnight Northerner passenger service until it was cancelled in November 2004. The EFs were not used initially on the Northern Explorer, KiwiRail experimented for a short while with towing the whole consist - including the diesel locomotive - over the central section. The need for the EF locomotives for freight services curtailed this.

Despite the NIMT railway electrification and the Auckland railway electrification being built to the same voltage (25kV AC), the EF class could not be used on Auckland's network due to that network being at a higher current than the NIMT. In order to run on Auckland's network, the EF class would require upgraded rectifiers.[9]

Only heavy repairs are undertaken at the main Hutt Workshops near Wellington which, due to the non-electrified section between Palmerston North and Waikanae (and Wellington's electrification being DC rather than AC), the locomotives must be towed by a diesel engine to access the workshops. All other work is carried out in Palmerston North.

From June 2006, the locomotives have been fitted with AAR couplers, each weighing over 400 kilograms (880 lb), to allow them to pull heavier trains.

In July 2010, EF 30065 and EF 30128 were assessed for a return to service, having been held in open storage (along with EF 30186) for many years at Palmerston North as surplus to operational requirements. It is hoped that reinstating the locomotives will help to ease pressure on the working fleet, especially as locomotives are currently regularly out of service for maintenance, modification and re-branding. EF 30065 was placed on second-hand bogies and moved to Hutt Workshops in August 2010 to begin the assessment, followed by EF 30186 in September. EF 30128 followed to Wellington in April 2011. It is anticipated that one of the locomotives will serve as a parts source to return the other two to service and the remaining hulk scrapped.

All EFs went through a minor upgrade to ensure reliability before a full overhaul is carried out. The upgrade included replacing the obsolete Locolog event recorder and vigilance system with the latest generation system known as Tranzlog. This system also includes fault recording.

EF 30013 was fitted with a replacement air compressor as a trial during 2012, which all locomotives will now receive. The original compressor has become uneconomic to rebuild and is becoming increasingly difficult to keep functioning. These locomotives can be recognised by a new louver being fitted to 2B side of the locomotive.

Livery

Three EF locomotives on a freight train north of Feilding. The first locomotive is in the International Orange livery.

Of the 17 EF Class locomotives currently in service, nine are painted in a livery other than the original International Orange scheme that they were introduced in:

• 10 in the International Orange ("Fruit Salad")
• 1 in Tranz Rail blue ("Cato Blue")
• 3 in Tranz Rail black ("Bumble-Bee")
• 6 in KiwiRail

The remaining three locomotives not in operational service (EFs 30065, 30128 and 30186) are all presently painted in the International Orange scheme. No EFs were ever painted in the Toll Rail "Corn Cob" scheme.

The rust removal and repaint into the new KiwiRail scheme began in September 2009 with 30163, followed by 30059 in February 2010, 30134 in March 2010, 30249 in April 2010, 30226 in July 2010 and 30203 in September 2014. It is expected that the remaining units will be rebranded in KiwiRail livery as they go through extended maintenance. So far, the KiwiRail repainting has been done at Hutt Workshops, which means the locomotives must be towed (as part of a diesel hauled freight service) to and from Wellington. The units painted in International Orange have the road numbers displayed in large type in the centre of the body (with the exception of EF 30007), while the other schemes have them in smaller type on the cabs.

Withdrawal and disposal

Seven EF class locomotives have been withdrawn from service:

EFs 30036 and 30088 were withdrawn from service following a derailment caused by a washout at Oio (north of Raurimu) on 7 August 1991 that also killed the locomotive engineer. After recovery from the site, the two heavily damaged locomotives were stored at Hutt Workshops until the decision was made that it was both uneconomic to repair the units and they would be surplus to existing requirements. Both were scrapped at Hutt Workshops in February 2007 and April 2003 respectively. Usable salvaged parts had been stripped to support the remainder of the fleet. 30007 was laid up during the mid-1990s but was returned to service not long after.

EFs 30065, 30128 and 30186 were laid up in late 1990s/early 2000s and were in long-term storage at Palmerston North as surplus to operational requirements. All three have since been moved to Hutt Workshops. Two other EF locos were withdrawn - 30111 was withdrawn in late 2015 due to requiring an air compressor change, and 30157 was withdrawn after catching fire.[10][11][12] Both locomotives are stored in Palmerston North.

In December 2016, it was announced that the EF class locomotives would be withdrawn over a two-year period and replaced by DL class locomotives, with the overhead lines remaining in place should the need for electric traction arise in the future.[13][14] EFs 30163 and 30249 were removed from service in the first quarter of 2018.

Overhauls

Following the 2017 general election KiwiRail and the new Labour-led Coalition Government announced on 30 October 2018 that capital funding would made available to refurbish 15 of the locomotives at the Hutt Workshops, extending the service life by 10 years for their continued use on the NIMT electrification in line with the new Government's energy and emissions policies.[15][16] EF30226 and EF30163 were transferred to the Hutt Workshops via the Wairarapa Line in November 2019 for overhaul by KiwiRail in collaboration with original manufacturer Brush Traction, now a subsidiary of Wabtec.[17] By this stage only eight remained in service.[18]

As at December 2020, work on the first locomotive, EF30226, had commenced at Hutt Workshops. It has been repainted in a new yellow and blue livery and named Tekapo.[19]

Outside New Zealand

The EF class design was used as the basis for the Eurotunnel Class 9 locomotives used in the Channel Tunnel by the Eurotunnel Shuttle service that was also built by Brush Traction and was scaled up to the standard rail gauge and larger loading gauge used in Europe.[20]

Notes

1. MU Electric Trains Commence NZ Suburban Service Truck & Bus Transportation August 1938 page 30
2. New Zealand electrifcation approved The Railway Magazine issue 952 August 1980 page 394
3. "Energy Data File". Ministry of Economic Development. 2 July 2009. Archived from the original on 5 December 2009. Retrieved 4 July 2009.
4. £30m HS deal Rail Enthusiast issue 30 March 1984 page 18
5. Robertson 2017, p. 30.
6. "NZR's locomotive fleet - where to from here?". Rails: 257. July 1990. ISSN 0110-6155.
7. "Payment withheld". Rails: 265. July 1990. ISSN 0110-6155.
8. "Queensland locos will help cope with traffic increase". Rails: 79. November 1995. ISSN 0110-6155.
9. Robertson 2017, p. 33.
10. "Electric locomotive fire at Palmerston North Terminal, 25 November 2015" (PDF). TAIC. 13 April 2017.
11. "Train fire at Palmerston North rail yard". Manawatu Standard. 25 November 2015. Retrieved 25 November 2015.
12. "Statuses for EF's 30111 and 30157 (Official Information Act request)". fyi.org.nz. KiwiRail. 13 February 2017. Retrieved 28 March 2017.
13. "KiwiRail announces fleet decision on North Island line". KiwiRail. 21 December 2016. Retrieved 22 December 2016.
14. Diesels to replace electrics in NZ Track & Signal May 2017 page 40
15. "Electric locomotives to continue with Government investment". KiwiRail. 30 October 2018. Retrieved 2 March 2019.
16. "Government Saves Electric Trains". Scoop Parliament. 30 October 2018. Retrieved 6 November 2018.
17. "New Zealand Railfan". 26 (1). Triple M Publishing. Summer 2020. ISSN 1173-2229. Cite journal requires |journal= (help)
18. KiwiRail electric operations reprieved International Railway Journal December 2018 page 9
19. "Down At the Station". New Zealand Railway Observer. New Zealand Railway and Locomotive Society. 77 (364). 2020. ISSN 0028-8624.
20. Semmens & Machefest-Tassin 1994.

References

• Parsons, David (2002). New Zealand Railway Motive Power 2002. New Zealand Railway and Locomotive Society. p. 64. ISBN 978-0-908573-78-3.
• Heath, Eric; Stott, Bob (1993). Classic Railcars, Electric and Diesel Locomotives Of New Zealand. Grantham House. ISBN 1869340418.
• Robertson, Niall (2017). "The EF Class Electrics". New Zealand Railfan. 23 (3): 33. ISSN 1173-2229.
• Semmens, P.W.B.; Machefest-Tassin, Y. (1994). Channel Tunnel Trains. Folkestone, Kent: Channel Tunnel Group Ltd. ISBN 1872009336.