Locomotive Feature (Part 1)

Below is some general information on diesel-electric locomotives, and the current rail industry in New Zealand.

Locomotive General Arrangement


(Sourced from Marks' Standard Handbook for Mechanical Engineers, Fig. 11.2.1)

The main components of the locomotive are shown above, with the diesel engine driving an electrical generator, which provides power to the traction motors. Controls on the engine operation and the electrical supply to the traction motors is also needed to get the best fuel economy, traction and power output.

Options for Procurement

New Zealand has taken advantage of several different procurement methods over the years to develop its fleet and replace older stock. Some have been imported and modified to suit New Zealand's conditions; others have been built from the ground up. Each method had advantages and disadvantages, such as lead time on delivery, reducing risk, factory cabability and setup, and economics. Often the deciding factors come down to politics.

The options available in procuring locomotives are:

  • Design and build from scratch (excluding engines and transmission)
  • Upgrade or rebuild existing locomotives
  • Assemble from kitsets
  • Buy in as built, to specification

Growing environmental issues such as exhaust emissions and regulations are also influencing decisions on locomotive purchases and upgrades. Global Locomotive is one company who are providing the services and know-how for repowering locomotives and utilising the latest breakthroughs in technology. Read more about upgrading using re-power kits here.

New Locomotives from China

In March 2009 funding was approved for the purchase of 20 new DK Class Locomotives to be built in China. This generated some controversy and political wrangling over two main issues:

  1. the reliability and quality of the locomotives
  2. the decision to outsource potential jobs and income during an economic downturn

Nevertheless, the technical specifications have been agreed to and construction is due to start this month with delivery of the first batch due in April next year.

While all efforts have been made to verify the information in these articles, we accept no responsibility for any inaccuracies which may appear.