K1 is an 0-4-0+0-4-0 articulated Garratt, one of a pair built in 1909 by Beyer
Peacock for the North-East Dundas Tramway, Tasmania. This unique and very special
locomotive holds a special place in the hearts of WHR supporters. This area
of the site, spread over several pages, introduces K1's history and revival.
What's a Garratt...? and what's a Beyer-Garratt...?
Garratt is a type of articulated steam locomotive. This means
that unlike a conventional locomotive, where the whole machine is carried on a
single set of frames, a Garratt has three separate frames. The power units,
front and rear, each have running gear much like a smaller conventional locomotive;
the boiler frame is pivoted between the power units, and carries
the boiler and cab. Water tanks are carried on both power units, with the rear
one also carrying the fuel supply. The design allows for a much larger boiler
than can be carried on a conventional locomotive of the same gauge, and the articulation
means the engine can traverse relatively tight curves. The design found particular
favour in Africa, where engines such as the East African Railways 59th Class (metre
gauge) and the South African Railways GMAM Class (3' 6" gauge) were among the
largest steam locomotives ever built, despite their narrow gauges. The name "Garratt"
derives from the engineer Herbert William Garratt, who devised the type, and developed
it in association with the Manchester firm of Beyer Peacock, which built most
of the Garratts used around the world - including all but one of those destined
for the Welsh Highland. Following the expiry of Garratt's patent in 1928, Beyer
Peacock no longer had exclusive rights to build Garratts, or to licence other
firms to build them. The firm thus termed all the Garratts it built subsequently
"Beyer-Garratts", to distinguish them from locos built by other firms. Thus K1
should properly be termed a Garratt, and the later South African
NGG16 class in use on the Welsh Highland comprises Beyer-Garratts.
Want to know more? See Gavin Hamilton's The
Garratt Locomotive site.
K1 - Technical Details
(N.B. Precise boiler figures are for the original
|Length over frames
||32 feet 2 inches
||0-4-0 + 0-4-0 T
|Wheelbase of each power unit
|Total heating surface
||628 square feet
|Heating surface of tubes
||568 sq. ft.
|Heating surface of firebox
||60 sq. ft.
||14.8 sq. ft.
||195 pounds per sq. inch
|High-pressure cylinders (x 2)
||11" diameter, 16" stroke
|Low-pressure cylinders (x 2)
||17" dia., 16" stroke
|Tractive effort @ 85% pressure
|Weight in working order
||33.5 tons (approx).
Back to rolling stock page
Authored by Ben Fisher; last updated
January 3rd, 2007