BNB VIb

Type and origin
Type and origin
Builder	Erste Böhmisch-Mährische Maschinenfabrik, Prague
Build date	1907
Total produced	2

BNB VIb
kkStB 265
ČSD 312.7
BNB VIb; kkStB 265; ČSD 312.7
Builder
Type and origin
Builder	Erste Böhmisch-Mährische Maschinenfabrik, Prague
Build date	1907
Total produced	2
Configuration:;
Specifications
Configuration:;
• Whyte	0-6-2T
Gauge	1,435 mm (4 ft 8+1⁄2 in) standard gauge
Driver dia.	930 mm (36+5⁄8 in)
Carrying wheel diameter	840 mm (33+1⁄8 in)
Wheelbase:
• Overall	4,800 mm (15 ft 9 in)
Length:;
• Over beams	9,836 mm (32 ft 3+1⁄4 in)
Adhesive weight	35.2 t (5.1 long tons; 5.7 short tons)
Empty weight	32.3 t (31.8 long tons; 35.6 short tons)
Service weight	44.6 t (43.9 long tons; 49.2 short tons)
Fuel capacity	4.7 m3 (170 cu ft) of coal
Water cap.	7.0 m3 (1,500 imp gal; 1,800 US gal)
Boiler:;
No. of heating tubes	192
Boiler pressure	12 kgf/cm2 (1,180 kPa; 171 lbf/in2)
Heating surface:
• Firebox	1.66 m2 (17.9 sq ft)
• Radiative	6.1 m2 (66 sq ft)
• Tubes	79.6 m2 (857 sq ft)
• Evaporative	85.7 m2 (922 sq ft)
Cylinders	2
Cylinder size	420 mm (16+9⁄16 in)
Piston stroke	480 mm (18+7⁄8 in)
Loco brake	Vacuum brake
Maximum speed
Performance figures
Maximum speed	45 km/h (28 mph)
Indicated power	352 PS (259 kW; 347 hp)
Numbers
Career
Numbers	BNB: 126, 127; kkStB: 265.01, 265.02; ČSD: 312.701, 312.702; DRB: 90 301, 90 302;
Retired	1949

The BNB VIb (six-B) was a class of two branch line tank locomotives of the Bohemian Northern Railway Company (Böhmische Nordbahn-Gesellschaft) for use on the Böhmisch Leipa-Steinschönau railway line. They later passed to the Imperial Austrian State Railways, who classified them as kkStB 265.

The two locomotives were built in Prague in 1907 by the Erste Böhmisch-Mährische Maschinenfabrik (later part of ČKD).

The locomotives spent their entire lives on their home line. In 1924 the Czechoslovakian State Railways (ČSD) grouped the engines into their ČSD Class 312.7. After the Second World War the Deutsche Reichsbahn gave them the designation DR Class 90.3.

On the introduction into service of new ČSD Class M 131.1 railcars, these locomotives were retired in 1949.

References

Hütter, Ingo (2021). Die Dampflokomotiven der Baureihen 60 bis 91 der DRG, DRB, DB, und DR (in German). Werl: DGEG Medien. pp. 462–463. ISBN 978-3-946594-21-5.