South Eastern & Chatham classes D und D1
Great Britain 1901 51 produced
The class D express locomotives were among Wainwright's first designs for the SE&CR. They were colorfully decorated to attract more public attention. They were built by different manufacturers, from 1905 also with Belpaire fireboxes. From 1921 Maunsell rebuilt some into the heavier class D1, which had a Belpaire firebox, a superheater, piston valves and a new cab. Eleven more were rebuilt between 1923 and 1926. A larger number of withdrawals took place from 1951 and the last rebuilt class D1 locomotives disappeared in 1961.
Technical data
General
| Property | round-topped firebox | Belpaire firebox | rebuilt D1 |
|---|---|---|---|
| Built | 1901-1907 | 1921-1927 | |
| Manufacturers | Ashford, Dübs & Co., Sharp, Stewart & Co., Robert Stephenson & Co., Vulcan Foundry | Ashford | |
| Wheel arrangement | 4-4-0 (American) | ||
| Gauge | 1,435 mm (Standard gauge) | ||
Dimensions and weights
| Property | round-topped firebox | Belpaire firebox | rebuilt D1 |
|---|---|---|---|
| Wheelbase | 6.20 m | ||
| Total wheelbase | 13.77 m | ||
| Service mass | 50.8 t | 53.1 t | 53.3 t |
| Adhesion mass | 33.4 t | 35.5 t | 34 t |
| Total mass | 91.1 t | 92.8 t | 93 t |
| Rigid wheelbase | 3.05 m | ||
| Axle load | 17.3 t | 17.9 t | |
| Water capacity | 15,002 l | 15,683 l | |
| Fuel capacity | 5.1 t (coal) | 4.1 t (coal) | |
Boiler
| Property | round-topped firebox | Belpaire firebox | rebuilt D1 |
|---|---|---|---|
| Grate area | 1.886 m² | 1.872 m² | 2.23 m² |
| Firebox surface | 11.52 m² | 12.635 m² | 11.811 m² |
| Tube heating surface | 128.299 m² | 129.693 m² | 106.825 m² |
| Evaporative heating surface | 139.819 m² | 142.328 m² | 118.635 m² |
| Total heating surface | 139.8 m² | 142.3 m² | 139.8 m² |
| Superheater surface | 21.182 m² |
Power plant
| Property | round-topped firebox | Belpaire firebox | rebuilt D1 |
|---|---|---|---|
| Driver diameter | 2,032 mm | ||
| Boiler pressure | 12.1 bar | 12.4 bar | |
| Expansion type | simple expansion | ||
| Cylinders | two, 489 x 660 mm | two, 483 x 660 mm | |
Power
| Property | round-topped firebox | Belpaire firebox | rebuilt D1 |
|---|---|---|---|
| Power source | steam | ||
| Estimated power | 559 kW (760 PS) | 574 kW (780 PS) | 783 kW (1,065 PS) |
| Starting effort | 79.7 kN | 79.9 kN | |
Calculated values
| Property | round-topped firebox | Belpaire firebox | rebuilt D1 |
|---|---|---|---|
| Factor of adhesion | 1 : 4.11 | 1 : 4.37 | 1 : 4.18 |
| Optimal speed | 43 km/h | 60 km/h | |
| Power-to-weight ratio | 11.0 kW/t | 10.8 kW/t | 14.7 kW/t |
| Heating Surface Equivalent | 197.4 m² | 205.5 m² | 220.1 m² |
| Cylinder volume/HSE | 1 : 1,256.22 | 1 : 1,206.81 | 1 : 1,097.92 |
| Adhesive weight/Total | 1 : 1.52 | 1 : 1.50 | 1 : 1.57 |
| Tractive force/Heating surface | 1 : 11.90 | 1 : 11.69 | 1 : 11.93 |
| Grate area/Heating surface | 1 : 74.14 | 1 : 76.03 | 1 : 62.70 |
| Firebox/Tube surface | 1 : 11.14 | 1 : 10.26 | 1 : 9.04 |
| Total/Superheater | 1 : 5.60 | ||
