A
Norwegian coupling (or meat chopper) is a manual
coupling consisting of a central buffer with a mechanical hook that drops into a slot in the central buffer. The system is only found on
narrow gauge railways of or less, such as
Western Australian Government Railways, the
Ffestiniog Railway and the
Welsh Highland Railway, where low speeds and reduced train loads allow a simpler system. Norwegian couplings are not particularly strong, and may be supplemented by auxiliary chains. Not all Norwegian couplings are compatible with one another as they vary in height and width, and may or may not be limited to one hook at a time. The Norwegian coupling was developed in Norway around 1870, when the main domestic railway net was built to narrow gauge. Later, during the 20th century, these lines were
rebuilt into or closed. This meant that the rolling stock needed to be replaced, and
buffers and chain coupler got used instead. Only museum railways, such as
Setesdalsbanen and
Urskog–Høland Line, use it in Norway nowadays. The
New Zealand Government Railways, during the 1970s, developed an extremely large and heavy-duty version of the chopper coupler. These were first applied to a fleet of
General Electric locomotives (U26C
class DX), which had arrived from the United States with auto couplers. However, they were converted once it was decided that these locomotives would operate on other than just the
North Island Main Trunk express freight trains.