Bavarian B XI

The Class B XI engines of the Royal Bavarian State Railways (Königlich Bayerische Staatsbahn) were built between 1895 and 1900 by the firm of Maffei for deployment in Bavaria. The first delivery comprised 39 vehicles with two-cylinder, saturated steam operation, a further 100 two-cylinder compound locomotives followed in the period up to 1900.

Bavarian B XI Zwilling (two-cylinder simple) DRG Class 36.7–8
Number(s)	K.Bay.Sts.E.: 1201–1239 DRG: 36 701 – 36 708
Quantity	39
Manufacturer	Maffei
Year(s) of manufacture	1892–1893
Retired	by 1926
Wheel arrangement	4-4-0
Axle arrangement	2′B n2
Track gauge	1,435 mm (4 ft 8 ^1⁄2 in)
Length over buffers	15,979 mm (52 ft 5 in) ^1 16,885 mm (55 ft 4 ^3⁄4 in) ^2
Wheelbase incl. tender	12,895 mm (42 ft 3 ^3⁄4 in) ^1 13,970 mm (45 ft 10 in) ^2
Service weight	50.4 t (49.6 long tons; 55.6 short tons)
Adhesive weight	28.5 t (28.0 long tons; 31.4 short tons)
Axle load	14.3 t (14.1 long tons; 15.8 short tons)
Top speed	90 km/h (56 mph)
Driving wheel diameter	1,870 mm (6 ft 1 ^5⁄8 in)
Leading wheel diameter	1,006 mm (3 ft 3 ^5⁄8 in)
Valve gear	Walschaerts (Heusinger), outside
No. of cylinders	Two, simple
Cylinder bore	430 mm (16 ^15⁄16 in)
Piston stroke	610 mm (24 in)
Boiler Overpressure	12 kg/cm^2 (1,180 kPa; 171 lbf/in^2)
Grate area	2.24 m^2 (24.1 sq ft)
Evaporative heating area	116.2 m^2 (1,251 sq ft)
Tender	bay 3 T 14.5 or bay 2′2′ T 18
Tender service weight	36.0 or 43.0 t (35.4 or 42.3 long tons; 39.7 or 47.4 short tons)
Water capacity	14.5 or 18.0 m^3 (3,190 or 3,960 imp gal; 3,830 or 4,760 US gal)
Fuel	6.0 or 6.5 t (5.91 or 6.40 long tons; 6.61 or 7.17 short tons) of coal
^1 with bay 3 T 14.5 tender ^2 with bay 2′2′ T 18 tender

Bavaian B XI Verbund (two-cylinder compound) DRG Class 36.7–8
Number(s)	K.Bay.Sts.E.: 1240–1339 DRG: 36 751 – 36 826
Quantity	100
Manufacturer	Maffei Krauss
Year(s) of manufacture	1895–1900
Retired	by 1931
Axle arrangement	2′B n2v
Length over buffers	16,986 mm (55 ft 8 ^3⁄4 in)
Wheelbase incl. tender	14,095 mm (46 ft 3 in)
Service weight	51.0 t (50.2 long tons; 56.2 short tons) 51.5 t (50.7 long tons; 56.8 short tons) ^3
Adhesive weight	28.8 t (28.3 long tons; 31.7 short tons) 29.6 t (29.1 long tons; 32.6 short tons) ^3
Axle load	14.4 t (14.2 long tons; 15.9 short tons) 14.8 t (14.6 long tons; 16.3 short tons) ^3
No. of cylinders	Two, compound
LP cylinder bore	670 mm (26 ^3⁄8 in)
HP cylinder bore	455 mm (17 ^15⁄16 in)
Piston stroke	610 mm (24 in)
Boiler Overpressure	13 kg/cm^2 (1,270 kPa; 185 lbf/in^2)
Grate area	2.26 m^2 (24.3 sq ft)
Evaporative heating area	116.8 m^2 (1,257 sq ft)
Tender	bay 2′2′ T 18
Tender service weight	43.0 t (42.3 long tons; 47.4 short tons)
Water capacity	18.0 m^3 (3,960 imp gal; 4,760 US gal)
Fuel	6.5 t (6.40 long tons; 7.17 short tons) of coal
^3 from no. 1318 Only differences from above shown

The Deutsche Reichsbahn took over 8 engines from the first batch as Class 36.7, with operating numbers 36 701 to 36 708, and 76 of the second batch, with numbers 36 751 to 36 826.

These steam locomotives were equipped with Bavarian 3 T 12, 3 T 14.5 and 2'2' T 18 tenders. These vehicles were the first locos that were give a four-axle tender.

See also

• Royal Bavarian State Railways
• List of Bavarian locomotives and railbuses

Sources

• This page incorporates a translation of the equivalent page on the German language Wikipedia