New Zealand Railways class K (1877)
New Zealand 1877 8 produced
After some British locomotives, the K class of 1877 was the first US locomotive to see service in New Zealand. Externally, compared to the British locomotives, it had many special features that caused a stir. These included the graceful bar frame, the swiveling trailing axle, many attachments located outside of the boiler and the rich decoration. The agile running characteristics in particular were apparently an advantage over the predecessors on the South Island of New Zealand. With the introduction of more powerful locomotives, they were used more on branch lines and some were moved to the North Island. After receiving new boilers, some with Belpaire fireboxes, they were retired in the 1920s.
Technical data
General
| Property | as built | rebuilt |
|---|---|---|
| Built | 1877-1878 | 1903 |
| Manufacturers | Rogers | |
| Wheel arrangement | 2-4-2 (Columbia) | |
| Gauge | 1,067 mm (Cape gauge) | |
Dimensions and weights
| Property | as built | rebuilt |
|---|---|---|
| Length | 13.89 m | |
| Wheelbase | 6.78 m | |
| Service mass | 23.7 t | 23.1 t |
| Adhesion mass | 15 t | 13.6 t |
| Total mass | 43.2 t | 42.6 t |
| Rigid wheelbase | 3.61 m | |
| Axle load | 7.5 t | 6.8 t |
| Water capacity | 5,682 l | |
| Fuel capacity | 2.2 t (coal) | |
Boiler
| Property | as built | rebuilt |
|---|---|---|
| Grate area | 0.819 m² | 0.938 m² |
| Evaporative heating surface | 54.72 m² | |
| Total heating surface | 54.7 m² |
Power plant
| Property | as built | rebuilt |
|---|---|---|
| Driver diameter | 1,257 mm | |
| Boiler pressure | 9 bar | 11 bar |
| Expansion type | simple expansion | |
| Cylinders | two, 305 x 508 mm | |
Power
| Property | as built | rebuilt |
|---|---|---|
| Power source | steam | |
| Estimated power | 205 kW (279 PS) | 298 kW (405 PS) |
| Starting effort | 28.6 kN | 35.2 kN |
Calculated values
| Property | as built | rebuilt |
|---|---|---|
| Factor of adhesion | 1 : 5.16 | 1 : 3.79 |
| Optimal speed | 43 km/h | 51 km/h |
| Power-to-weight ratio | 8.7 kW/t | 12.9 kW/t |
| Adhesive weight/Total | 1 : 1.57 | 1 : 1.70 |
| Tractive force/Heating surface | 1 : 10.92 | |
| Grate area/Heating surface | 1 : 66.81 |