Prussian P 4
Type and origin Builder Henschel Build date 1898 Total produced 1
Specifications Configuration: ​  • Whyte 4-4-0  • UIC 2'B h2  • German P 24.45 Gauge 1,435 mm (4 ft 8+1⁄2 in) Coupled dia. 1,750 mm Carrying wheel diameter 1,000 mm Wheelbase: ​  • Overall 7,400 mm Length: ​  • Over beams 16,411 mm Axle load 15.5 t Adhesive weight 31.0 t Empty weight 44.6 t Service weight 49.1 t Water cap. 15.0 m3 Boiler: ​ No. of heating tubes 141 No. of smoke tubes 1 fire tube Boiler pressure 12 bar Heating surface: ​  • Tubes 76.2 m2  • Firebox 2.32 m2  • Radiative 8.9 m2  • Evaporative 85.1 m2 Superheater: ​  • Heating area 21.0 m2 Cylinders 2 Cylinder size 460 mm Piston stroke 600 mm
Performance figures Maximum speed 90 km/h Indicated power 675 kW (900 PS)
Career Retired 1921

The Prussian P 4 was a derivative of the P 4.1 (Hanover variant) and the second superheated steam locomotive in the world.

Design

The engine was based on that of the Class P 4.1 that had Hanomag had produced in large numbers since 1892. It had slightly larger wheels and, due to its new design, significantly fewer heating tubes. The superheater and the steam engine were entirely independent designs.

Service and preservation

In 1898 a one-off was delivered by Hanomag to the Prussian state railways. The economy of the superheated system was soon proven in 1899 by the engine during trial runs from Kassel. Apart from a short stay at Halle the engine was assigned to Kassel as Cassel 131 and, from 1906, as P 4 Cassel 1846. In 1921, after the First World War, the engine was mothballed, along with many other machines of similar class. With its sectioned boiler the P 4 stood for a long time in the Transport and Construction Museums, part of Museum of the Present at Hamburger Bahnhof in Berlin.

See also

• Prussian state railways
• List of Prussian locomotives and railbuses
• List of preserved steam locomotives in Germany

References

Wikimedia Commons has media related to Prussian P 4.