Bavarian D X

The Bavarian Class D X engines were saturated steam locomotives of the Royal Bavarian State Railways (Königlich Bayerische Staatsbahn).

Bavarian D X DRG Class 98.77
Number(s)	K.Bay.Sts.E: 931–935, 99, 1961–1963 DRG 98 7701 – 98 7709
Quantity	9
Manufacturer	Krauss, Munich
Year(s) of manufacture	1890, 1893
Retired	1925–1931
Wheel arrangement	0-6-2T
Axle arrangement	C1′ n2t
Track gauge	1,435 mm (4 ft 8 ^1⁄2 in)
Length over buffers	9,310 mm (30 ft 6 ^1⁄2 in)
Service weight	42.7 t (42.0 long tons; 47.1 short tons)
Adhesive weight	33.0 t (32.5 long tons; 36.4 short tons)
Axle load	11.0 t (10.8 long tons; 12.1 short tons)
Top speed	45 km/h (28 mph)
Indicated Power	300 PS (221 kW; 296 hp)
Driving wheel diameter	985 or 1,006 mm (3 ft 2 ^3⁄4 in or 3 ft 3 ^5⁄8 in)
Trailing wheel diameter	780 or 800 mm (2 ft 6 ^3⁄4 in or 2 ft 7 ^1⁄2 in)
No. of cylinders	2
Cylinder bore	390 mm (15 ^3⁄8 in)
Piston stroke	508 mm (20 in)
Boiler Overpressure	12 kgf/cm^2 (1,180 kPa; 171 lbf/in^2)
Grate area	1.40 m^2 (15.1 sq ft)
Evaporative heating area	71.71 m^2 (771.9 sq ft)
Locomotive brakes	Hardy vacuum brakes, later compressed-air brakes

The locomotives, which were built by Krauss were similar to the Class D VIII, but were smaller and lighter. Like the D VIII they had a trailing axle, that was connected to the final coupled axle by a Krauss-Helmholtz bogie.

In 1890 the first six were built, followed in 1893 by three more with somewhat larger wheels. The first engine was only 8,880 mm long due to the lack of a coal bunker on the driver's cab.

All the vehicles were taken over by the Deutsche Reichsbahn-Gesellschaft in 1925 as DRG Class 98.77 and remained in service until 1931. Only numbers 98 7706 and 98 7707 were retired shortly after the renumbering.

See also

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