Great Western Railway class 2600 “Aberdare”
For the coal traffic between Aberdare and Swindon, the GWR had 81 2-6-0 locomotives built from 1900 onwards, also called the “Aberdare class”. It was built under Dean and the first to be built, number 33, still had a conventional boiler with a Belpaire firebox, which the 4-4-0 express train locomotives of the Bulldog class also had. All others already got Churchward's tapered boiler. The last nine were rebuilds of the class 2602 “Kruger”.
A striking feature was the massive outside frame. The first ones received a superheater as early as 1908. The first withdrawals took place from 1934, but some were reactivated again during the Second World War. There were twelve remaining when British Railways was founded, but they disappeared by 1949.
Technical data
General
| Property | as built | superheated |
|---|---|---|
| Built | 1900-1906 | |
| Manufacturers | Swindon | |
| Wheel arrangement | 2-6-0 (Mogul) | |
| Gauge | 1,435 mm (Standard gauge) | |
Dimensions and weights
| Property | as built | superheated |
|---|---|---|
| Wheelbase | 6.86 m | |
| Total wheelbase | 13.92 m | |
| Service mass | 54.3 t | 57.7 t |
| Adhesion mass | 47.6 t | 50.4 t |
| Total mass | 87.3 t | 106.1 t |
| Rigid wheelbase | 4.57 m | |
| Axle load | 16.1 t | 17.8 t |
| Water capacity | 13,639 l | 18,185 l |
Boiler
| Property | as built | superheated |
|---|---|---|
| Grate area | 1.999 m² | 1.91 m² |
| Firebox surface | 11.589 m² | 11.957 m² |
| Tube heating surface | 142.891 m² | 125.354 m² |
| Evaporative heating surface | 154.479 m² | 137.311 m² |
| Total heating surface | 154.5 m² | 160.5 m² |
| Superheater surface | 23.226 m² |
Power plant
| Property | as built | superheated |
|---|---|---|
| Driver diameter | 1,410 mm | |
| Boiler pressure | 13.8 bar | |
| Expansion type | simple expansion | |
| Cylinders | two, 457 x 660 mm | |
Power
| Property | as built | superheated |
|---|---|---|
| Power source | steam | |
| Estimated power | 615 kW (836 PS) | 783 kW (1,065 PS) |
| Starting effort | 114.8 kN | |
Calculated values
| Property | as built | superheated |
|---|---|---|
| Factor of adhesion | 1 : 4.06 | 1 : 4.31 |
| Optimal speed | 32 km/h | 42 km/h |
| Power-to-weight ratio | 11.3 kW/t | 13.6 kW/t |
| Heating Surface Equivalent | 212.4 m² | 243.5 m² |
| Cylinder volume/HSE | 1 : 1,020.78 | 1 : 890.34 |
| Adhesive weight/Total | 1 : 1.14 | |
| Tractive force/Heating surface | 1 : 15.52 | 1 : 14.93 |
| Grate area/Heating surface | 1 : 77.28 | 1 : 84.05 |
| Firebox/Tube surface | 1 : 12.33 | 1 : 10.48 |
| Total/Superheater | 1 : 5.91 | |