NZR DQ class

DQ / QR class
DQ 6324 at Palmerston North, New Zealand
Power type	Diesel-electric
Builder	Commonwealth Engineering, Rocklea, Queensland, Australia
Build date	1967
UIC classification	Co-Co
Wheel diameter	1.250 m
Wheelbase	13.550 m between bogies 2.580 m between axles in each bogie
Length	16.3 m m
Locomotive weight	92 tonnes (91 long tons; 101 short tons)
Top speed	80 km/h
Power output	1,120 kW (1,500 hp)
Tractive effort	1460: 1,065 kW (1,428 hp) 1502: 1,230 kW (1,650 hp)
Career	Tranz Rail, Toll Rail, KiwiRail, TasRail
Number in class	25 (1460: 21 1502: 4) 15 rebuilt as DQ class 7 withdrawn, 3 in service, 15 sold to TasRail (12 DQ / 3 QR).
First run	1964 (QR) 1995 (NZ)
Disposition	3 in service, 6 withdrawn, 15 sold to TasRail

The New Zealand DQ and QR class locomotives are two classes of mainline diesel-electric locomotives in New Zealand and Tasmania, Australia. Originally Queensland Rail 1460 and 1502 class, they were purchased by New Zealand Rail Limited in 1995 to be rebuilt, as a cheaper alternative to buying new locomotives.

Introduction

They arrived in New Zealand as the QR classes 1460 and 1502, most of which were then rebuilt by Hutt Workshops into the DQ class. During rebuilding their cabs were modified with the addition of two large windows, nose lowered, a computerised control system installed, upgrading of the engines, fitting of dynamic brakes and the addition of noise insulation. The QR locomotives that were not rebuilt received only minimal alteration before being used as trailing locomotives. All were painted in Tranz Rail's corporate livery of light blue and yellow before being put into service.

Service

They are not favoured by their crews due to complaints of rough riding and excessive cab noise.

They are also considered unreliable by senior management (DQ units in Tasmania have a high rate of generator failure), so they are now mainly used for short-haul runs, such as on the final leg of coal trains from the West Coast between Christchurch and the port of Lyttelton and on the Ohai Branch Line to and from Invercargill, hauling containerized coal trains. They are also used as bankers to help trains up the steep grade out of Picton.

As of 2011, only three DQ locomotives are in service (all in the South Island); the remaining QR units that were not rebuilt have been sold after lengthy periods of storage at the Hutt Workshops. DQ 6347 suffered damage when toppled onto its side after derailing on entry to the Picton yard in late 2009, after which it was sent to Hutt Workshops for repair. It remained out-of service with little work undertaken on it for months but was eventually repaired and returned to service in October 2011. DQ 6376 is currently out of service after it was derailed when the freight train it was part of struck a slip south of Kaikoura in June 2011. In both cases the DQ was operating as the trailing locomotive (in multiple with another) and unoccupied at the time of derailment.

Exports to Tasmania

A DQ class and two D class TasRail locomotives on a train at Glenorchy, Tasmania.

In 1998 Tranz Rail began to export locomotives to Tasmania for use on TasRail, then part-owned by Tranz Rail. In total, twelve DQ were exported, along with three unrebuilt QR class.

Class register

Key:	In service	Out of service	Auckland Transport service	Preserved	Overhaul	Scrapped

QR no.	TMS no.	TasRail no.	Introduced	Allocated to	Current livery	Status
1460	DQ 6382		01997-09 September 1997	South Island	Tranz Rail Blue	In service
1462	QR 2027		01997-10 October 1997			Stored Mount Vernon, Illinois
1465	DQ 6416	DQ 2006	01999-02 February 1999			Sold to TasRail
1466	QR 2033	DQ 2010	01999-02 February 1999			Sold to TasRail
1467	DQ 6376		01998-05 May 1998	South Island	Tranz Rail Blue	Out of service after hitting a slip in Kaikoura
1468	DQ 6330	DQ 2005	01997-12 December 1997			Sold to TasRail
1472	DQ 6353	DQ 2008	01998-04 April 1998			Sold to TasRail
1473	DQ 6324		01997-09 September 1997	South Island	Toll Rail "Corn Cob"	In service
1475	QR 2056		01997-09 September 1997			Sold to TasRail. Withdrawn.
1477	QR 2062		01997-10 October 1997			Sold to TasRail. Withdrawn.
1481	DQ 6347		01998-02 February 1998	South Island	Toll Rail "Corn Cob"	In service
1485	DQ 6399	DQ 2007	01999-02 February 1999			Sold to TasRail
1488	QR 2079		01997-11 November 1997			Stored Mount Vernon, Illinois
1489	QR 2085		01998-12 December 1998			Stored Mount Vernon, Illinois
1491		DQ 2009	01999-09 September 1999			Sold to TasRail
1493	QR 2102		01997-11 November 1997			Sold to TasRail. Withdrawn.
1495		DQ 2011	01999-09 September 1999			Sold to TasRail.
1497		DQ 2012	01999-09 September 1999			Sold to TasRail
1499						Frame only, stored Hutt Workshops.
1500						Stored Mount Vernon, Illinois
1501						Stored Mount Vernon, Illinois
1502	QR 3032	DQ 2004	01997-12 December 1997			Sold to TasRail.
1508	DQ 6036	DQ 2003	01998-12 December 1998			Sold to TasRail
1521	DQ 6007	DQ 2001	01996-10 October 1996			Sold to TasRail. Rebuilt 2010.
1522	DQ 6013	DQ 2002	01998-08 August 1998			Sold to TasRail

External links

• TasRail - Class DQ
• TasRail - Class QR
• Queensland Rail - Class 1460
• Queensland Rail - Class 1502
• http://www.railsoc.org.nz/pub/books.htm Parsons, David - New Zealand Railway Motive Power 2002