Prussian G 71
German Reichsbahn class 550-6
The G 71 was a heavy freight locomotive that was built in large numbers from 1893 and was in use for a very long time due to its simple design. Although a compound development was already in production from 1895 with the G 72, the G 71 with the simpler powerplant and better suitability for short distances was also produced at an unchanged rate.
With a low top speed of just 45 km/h, it offered enough tractive effort for most heavy freight trains at the time and was therefore mainly used in the more mountainous areas of Prussian territory. A total of 1,002 G 71 were manufactured by Vulcan for Prussia until 1909 and Schwartzkopff manufactured three more for the Lübeck-Büchener Eisenbahn. When there was a need for an economic freight locomotive that was very easy to maintain during the First World War, an additional 200 units of the now 20-year-old design were ordered.
The Reichsbahn took over 680 in 1923 and renumbered them 55 001 to 660. In the 1930s, many faster standard designs became available, which gradually pushed the G 71 onto branch lines and into shunting service. Here, however, it was able to score again with its low axle load and low consumption, what ensured a long life. The Bundesbahn finally retired the last G 71 in 1957 and the Reichsbahn not until 1966, when all G 72 had long since disappeared. This career was very long, especially for a saturated locomotive, which testifies to its qualities.
Technical data
General
- Built
- 1893-1909, 1916-1917
- Manufacturers
- Vulcan, Hanomag, Schichau, Linke-Hofmann, Hartmann, BMAG, Henschel, Hohenzollern, O&K, Borsig, Jung
- Wheel arrangement
- 0-8-0 (Eight-coupled)
- Gauge
- 1,435 mm (Standard gauge)
Dimensions and weights
- Length
- 16.61 m
- Wheelbase
- 4.50 m
- Total wheelbase
- 11.77 m
- Empty mass
- 46 t
- Service mass
- 52.6 t
- Adhesion mass
- 52.6 t
- Total mass
- 85.9 t
- Rigid wheelbase
- 4.50 m
- Axle load
- 13.3 t
- Water capacity
- 12,000 l
- Fuel capacity
- 3 t (coal)
Boiler
- Grate area
- 2.28 m²
- Firebox surface
- 10.25 m²
- Tube heating surface
- 141.23 m²
- Evaporative heating surface
- 151.48 m²
- Total heating surface
- 151.5 m²
Power plant
- Driver diameter
- 1,250 mm
- Boiler pressure
- 12 bar
- Expansion type
- simple expansion
- Cylinders
- two, 520 x 630 mm
Power
- Power source
- steam
- Estimated power
- 550 kW (748 PS)
- Top speed
- 45 km/h
- Starting effort
- 139.0 kN
Calculated values
- Factor of adhesion
- 1 : 3.71
- Optimal speed
- 24 km/h
- Power-to-weight ratio
- 10.5 kW/t
- Heating Surface Equivalent
- 202.7 m²
- Cylinder volume/HSE
- 1 : 1,319.92
- Adhesive weight/Total
- 1 : 1.00
- Tractive force/Heating surface
- 1 : 19.17
- Grate area/Heating surface
- 1 : 66.44
- Firebox/Tube surface
- 1 : 13.78