London, Midland & Scottish class 4P Compound 4-4-0
Since the Midland Railway had good experiences with their class 1000 compound 4-4-0s, the LMS ordered locomotives which were nearly identical. Out of a total of 195, 75 each were built by Vulcan Foundry and Derby, 25 by North British and 20 by Horwich.
Like the Midland locomotives, they were three-cylinder compounds with a central high pressure cylinder and two slightly larger outside low pressure cylinders. Changes included driving wheels which were three inches smaller, a superheater that was installed from the beginning and cylinders which measured 19 3/4 and 21 3/4 inches in diameter.
After only a short time, the cylinder diameters were changed to 19 and 21 inches to equal the Midland locomotives. They were used in the same tasks as their predecessors, what meant light, fast expresses. Their service life was longer than that of their predecessors, so the withdrawals took place between 1952 and 1961.
Technical data
General
- Built
- 1924-1932
- Manufacturers
- Derby, Horwich, North British, Vulcan Foundry
- Wheel arrangement
- 4-4-0 (American)
- Gauge
- 1,435 mm (Standard gauge)
Dimensions and weights
- Length
- 17.27 m
- Wheelbase
- 7.39 m
- Service mass
- 62.7 t
- Adhesion mass
- 39.8 t
- Total mass
- 105.1 t
- Rigid wheelbase
- 2.92 m
- Axle load
- 19.9 t
- Water capacity
- 15,910 l
- Fuel capacity
- 5.6 t (coal)
Boiler
- Grate area
- 2.638 m²
- Firebox surface
- 13.685 m²
- Tube heating surface
- 108.669 m²
- Evaporative heating surface
- 122.353 m²
- Superheater surface
- 27.035 m²
- Total heating surface
- 149.4 m²
Power plant
- Driver diameter
- 2,057 mm
- Boiler pressure
- 13.8 bar
- Expansion type
- compound
- Cylinders
- three, HP: 483 x 660 mm and LP: 533 x 660 mm
Power
- Power source
- steam
- Estimated power
- 969 kW (1,317 PS)
- Starting effort
- 72.3 kN
- Starting effort simple
- 86.7 kN
Calculated values
- Factor of adhesion
- 1 : 5.41
- Optimal speed
- 82 km/h
- Power-to-weight ratio
- 15.5 kW/t
- Heating Surface Equivalent
- 244.8 m²
- Cylinder volume/HSE
- 1 : 1,192.08
- Adhesive weight/Total
- 1 : 1.57
- Tractive force/Heating surface
- 1 : 10.10
- Grate area/Heating surface
- 1 : 56.63
- Firebox/Tube surface
- 1 : 7.94
- Total/Superheater
- 1 : 4.53