Prussian T 6

The T 6 of the Prussian State Railways were a class of twelve passenger tank locomotives. They were intended as an alternative to the Prussian T 11 and T 12 classes on the routes of the Berlin Stadt (city), Ring and suburban network. A total of twelve locomotives were built in 1902 by Berliner Maschinenbau AG. Two went to the Altona Division, the other ten to the Berlin Division. The design was unusual – being a three-cylinder design. In comparison to the T 11 and T 12, they were the least economical of the three classes. They were also other technical reasons why no more T 6 locomotives were built.^[1][2]

Prussian T 6 PKP OKl1
Type and origin Builder Berliner Maschinenbau Build date 1902 Total produced 12
Specifications Configuration: ​  • Whyte 2-6-2T Gauge 1,435 mm (4 ft 8+1⁄2 in) Leading dia. 1,000 mm (3 ft 3+3⁄8 in) Driver dia. 1,500 mm (4 ft 11 in) Trailing dia. 1,000 mm (3 ft 3+3⁄8 in) Length: ​  • Over beams 13,400 mm (43 ft 11+1⁄2 in) Axle load 16.6 t (16.3 long tons; 18.3 short tons) Adhesive weight 48.8 t (48.0 long tons; 53.8 short tons) Service weight 79.0 t (77.8 long tons; 87.1 short tons) Fuel capacity 2.5 t (5,500 lb) of coal Water cap. 6.7 m3 (1,500 imp gal; 1,800 US gal) Boiler pressure 14 kgf/cm2 (1.37 MPa; 199 lbf/in2) Heating surface: ​  • Firebox 2.30 m2 (24.8 sq ft)  • Evaporative 154.50 m2 (1,663.0 sq ft) Cylinders 3 Cylinder size 500 mm (19+11⁄16 in) Piston stroke 630 mm (24+13⁄16 in)
Performance figures Maximum speed 75 km/h (47 mph)
Career Retired Early 1920s

The locomotives were later dispersed to other railway divisions. After World War I, five went to the Polish State Railways (PKP), who classified them as OKl1. The locomotives that remained in Germany were retired by the early 1920s^[2]