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JNR D50 Class Steam Locomotive

JNR steam locomotive D50 class
D50 140 Nov.2005 Umekoji Steam Locomotives Museum

To cope with the increasing freight demand from the 1920s, more powerful locomotives than the type 9600 were required. As a result, the D50 class was developed, with 380 units built between 1923 and 1931 by Kisha Seizo, Kawasaki, Hitachi, and Nippon-Sharyo. Originally called the type 9900, it was formally renamed the type D50 in 1928. It was used for main line freight transportation in various regions all over Japan. Of these type 9900s, 1 was modified and offered to the North China Transportation Company in the Japanese-occupied Chinese mainland. After the war, it became the type Mika-16 in the People's Republic of China, and it became the type JF16 in 1953, but as of 1955 it was no longer used. Because of its heavy body, this locomotive was moved to local lines while the D51 and D52 were used as the main steam locomotive types for freight service. In addition, 78 were converted to the type D60 to lighten the axle weight. The last was used until 1971, and 2 of them are currently in static preservation (refers to locomotives that are preserved in a way that does not allow them to be immediately operated, and/or that are simply on display).

Data of D50 Class

Wheel arrangement 2-8-2 Driving Wheel Diameter(mm) 1,400
Loco. Weight in Working Order(t) 78.14 Maximum Axle Load(t) 14.99
Tender Weight in Working Order(t) 49.00 Boiler Pressure(kg/cm²) 13.00
Heating Surface Area(㎡) 222.30 Cylinder Dimensions(mm) 570×660
Grate Area(㎡) 3.25 Overall Length(mm) 20,003
Boiler Water Capacity (m³) 7.4 Total Height(mm) 3,955
Loading Capacity of Water(m³) 17.0 Locomotive Length(mm) 12,663
Fuel Capacity(t) 12.0 Tender Length(mm) 7,340
Weight on Driving Wheels(t) 58.79 Boiler Center Height(mm) 2,500