Uganda Railway classes S and MS
Kenya-Uganda Railway classes S and MS and East African class 10
In 1914, Nasmyth, Wilson & Co. delivered eight tank locomotives for shunting to the Uganda Railway which had been designed by Rendel, Palmer and Tritton. Three of these where the 2-6-2T class S, while the other five were the 2-6-4T class MS. The locomotives with a trailing bogie were also suited for short line trips with their larger water and coal supplies. A special feature was a lock-up valve that could be opened to allow the water to distribute in a way that the axle load didn't exceed nine tons.
Around 1920, they were converted to oil-firing. Later in their career with the Kenya-Uganda Railway and the East African Railways, they got an additional water tender and were used on secondary lines. Today 1003 is on static display at Jamhuri Park, Nairobi.
Technical data
General
| Property | S | MS |
|---|---|---|
| Built | 1914 | |
| Manufacturers | Nasmyth, Wilson & Co. | |
| Wheel arrangement | 2-6-2T (Prairie) | 2-6-4T (Adriatic) |
| Gauge | 1,000 mm (Meter gauge) | |
Dimensions and weights
| Property | S | MS |
|---|---|---|
| Length | 10.51 m | 11.80 m |
| Wheelbase | 7.32 m | 8.75 m |
| Service mass | 45.6 t | 53.2 t |
| Rigid wheelbase | 3.05 m | |
| Water capacity | 3,638 l | 5,455 l |
| Fuel capacity | 1.8 t (coal) | 6.1 t (coal) |
Boiler
| Property | S | MS |
|---|---|---|
| Grate area | 1.189 m² | |
| Firebox surface | 12.263 m² | 12.077 m² |
| Tube heating surface | 95.319 m² | 95.133 m² |
| Evaporative heating surface | 107.582 m² | 107.21 m² |
| Total heating surface | 107.6 m² | 107.2 m² |
Power plant
| Property | S | MS |
|---|---|---|
| Driver diameter | 1,092 mm | |
| Boiler pressure | 11 bar | |
| Expansion type | simple expansion | |
| Cylinders | two, 381 x 559 mm | |
Power
| Property | S | MS |
|---|---|---|
| Power source | steam | |
| Estimated power | 373 kW (507 PS) | |
| Starting effort | 69.6 kN | |
Calculated values
| Property | S | MS |
|---|---|---|
| Optimal speed | 32 km/h | |
| Power-to-weight ratio | 8.2 kW/t | 7.0 kW/t |
| Heating Surface Equivalent | 168.9 m² | 167.6 m² |
| Cylinder volume/HSE | 1 : 754.40 | 1 : 760.27 |
| Tractive force/Heating surface | 1 : 13.52 | 1 : 13.57 |
| Grate area/Heating surface | 1 : 90.48 | 1 : 90.17 |
| Firebox/Tube surface | 1 : 7.77 | 1 : 7.88 |
