South Indian class M
Chief engineer Robert White had five ten-wheelers built for mail traffic on the meter-gauge lines of the South Indian, including those leading to Ceylon. These used the BESA standard design and came from Hawthorn, Leslie & Co. of Newcastle. Thus they had 16.5 inch diameter outside cylinders, 57 inch diameter coupled wheels and Belpaire firebox with a long narrow grate.
However, only one engine was built according to the design using saturated steam, the others being the first narrow-gauge superheated locomotives in India. With the results of the five locomotives, White was able to substantiate his assumption that superheated steam should have a clear advantage despite the greater complexity. Thus, the only saturated engine was soon rebuilt with a superheater.
Technical data
General
- Built
- 1913
- Manufacturers
- Hawthorn, Leslie & Co.
- Wheel arrangement
- 4-6-0 (Ten-wheeler)
- Gauge
- 1,000 mm (Meter gauge)
Dimensions and weights
- Wheelbase
- 6.44 m
- Total wheelbase
- 12.85 m
- Service mass
- 35.9 t
- Adhesion mass
- 27.4 t
- Total mass
- 60.9 t
- Rigid wheelbase
- 3.66 m
- Axle load
- 9.1 t
- Water capacity
- 9,093 l
- Fuel capacity
- 5.6 t (coal)
Boiler
- Grate area
- 1.486 m²
- Firebox surface
- 10.034 m²
- Tube heating surface
- 66.018 m²
- Evaporative heating surface
- 76.051 m²
- Superheater surface
- 18.079 m²
- Total heating surface
- 94.1 m²
Power plant
- Driver diameter
- 1,448 mm
- Boiler pressure
- 11.7 bar
- Expansion type
- simple expansion
- Cylinders
- two, 419 x 559 mm
Power
- Power source
- steam
- Estimated power
- 522 kW (710 PS)
- Starting effort
- 67.5 kN
Calculated values
- Factor of adhesion
- 1 : 3.98
- Optimal speed
- 47 km/h
- Power-to-weight ratio
- 14.6 kW/t
- Heating Surface Equivalent
- 162.4 m²
- Cylinder volume/HSE
- 1 : 949.47
- Adhesive weight/Total
- 1 : 1.31
- Tractive force/Heating surface
- 1 : 14.99
- Grate area/Heating surface
- 1 : 63.34
- Firebox/Tube surface
- 1 : 6.58
- Total/Superheater
- 1 : 4.21
