JNR Class D50

D50 319 in 1935

Type and origin Power type Steam Designer Tokichi Ogasawara Builder Kawasaki Heavy Industries Rolling Stock Company (204) Hitachi (80) Kisha Seizo (69) Nippon Sharyo (27) Build date 1923–1931 Total produced 380

Specifications Configuration 2-8-2 UIC class 1′D1′ h2 Gauge 1,067 mm (3 ft 6 in) Driver dia. 1,400 mm (4 ft 7 in) Length 17,248 mm (56 ft 7 in) Height 3,955 mm (12 ft 11 ^3⁄4 in) Axle load 14.70 tonnes (14.47 long tons; 16.20 short tons) Loco weight 78.14 tonnes (76.91 long tons; 86.13 short tons) Tender weight 49 tonnes (48 long tons; 54 short tons) Firebox:  • Firegrate area 3.25 m^2 (35.0 sq ft) Boiler: ​  • Tube plates 5,500 millimetres (18 ft ^1⁄2 in)  • Small tubes 57 mm (2 ^1⁄4 in), 90 off  • Large tubes 140 mm (5 ^1⁄2 in), 28 off Boiler pressure 13.0 kg/cm^2 (1.27 MPa; 185 psi) Heating surface:  • Tubes and flues 142.7 m^2 (1,536 sq ft)  • Firebox 13.5 m^2 (145 sq ft) Superheater: ​  • Heating area 64.4 m^2 (693 sq ft) Cylinders Two, outside Cylinder size 570 mm × 660 mm (22 ^7⁄16 in × 26 in)

Performance figures Maximum speed 70 km/h (43 mph) Tractive effort 165.977 kN (37,313 lbf)

Career Operators Japanese Government Railways Japanese National Railways Class JGR: 9900 → D50 JNR: D50 Numbers 9900–9999, 19900–19999, 29900–29975 → D50 1 to D50 380 Retired 1965 Preserved D50 25, D50 140 Disposition Two preserved, remainder scrapped

The Class D50 is a type of 2-8-2 steam locomotive built by the Japanese Government Railways (JGR), the Japanese National Railways (JNR) and various manufacturers from 1923 to 1931. The class name indicates that the locomotive has four sets of driving wheels (D) and belongs to one of the classes of tender locomotive allocated a number in the series 50 to 99 in the Japan Railways locomotive numbering and classification scheme of 1928.

The design of the D50 was based on the JNR Class 9600 which was introduced in 1916. A total of 380 Class D50 locomotives were built.

Preserved examples

Two D50s are preserved in Japan.^[1]

• D50 25　Park in Kitami, Hokkaido
• D50 140 At the Umekoji Steam Locomotive Museum in Kyoto

• 
  D50 25 in Kitami, Hokkaido
• 
  D50 140 at Umekoji Steam Locomotive Museum

See also

• Japan Railways locomotive numbering and classification

References

1. Sasada, Masahiro (September 2012). 国鉄&JR保存車大全 [JNR & JR Preserved Rolling Stock Complete Guide]. Tokyo, Japan: Ikaros Publications Ltd. p. 133. ISBN 978-4863206175.