JNR Class DF50

The Class DF50 (DF50形) is a class of Bo-Bo-Bo wheel arrangement diesel–electric locomotives operated by Japanese National Railways (JNR) in Japan from 1957 until 1983.^[1]

Class DF50
A pair of DF50s on a farewell tour in 1983
Type and origin Power type Diesel–electric Builder Hitachi Kawasaki Kisha Seizō Mitsubishi Nippon Sharyō Toshiba Build date 1957–1963 Total produced 138
Specifications Configuration: ​  • UIC Bo'Bo'Bo'  • Commonwealth Bo-Bo-Bo Gauge 1,067 mm (3 ft 6 in) Wheel diameter 800 mm (2 ft 7 in) Length 16,400 mm (53 ft 10 in) Width 2,932 mm (9 ft 7.4 in) Height 3,987 mm (13 ft 1.0 in) Loco weight 85.1 t Traction motors MT48 x 6
Performance figures Maximum speed 90 km/h (55 mph) Power output 1,060 hp (DF50-0), 1,200 hp (DF50-500)
Career First run 1957 Last run 1983 Preserved 3

Variants

DF50-0

The first batch of 65 locomotives was built between 1957 and 1962 with Sulzer 8-cylinder 8LDA25A 1,060 hp diesel engines.^[1][2] Production was shared between Kisha Seizō, Mitsubishi, and Nippon Sharyō.^[2]

• 
  DF50 1 on a passenger service in 1979
• 
  DF50 65 on a freight working in 1982

DF50-500

A later batch of 73 locomotives was built between 1958 and 1963 with MAN V6 V22/30 1,200 hp diesel engines.^[1][2] Production was shared between Hitachi, Kawasaki, and Toshiba.^[2]

• 
  DF50 573 on a passenger service in Shikoku in 1979

Operations

A pair of Class DF50s on a limestone freight working in 1983

Class DF50 locomotives were intended for use on both passenger and freight services, and included a steam generator for train heating.^[3] They operated on the following lines, including use hauling "Blue Train" sleeping car services.^[2]

• Hokuriku Main Line
• Sanin Main Line
• Dosan Line (Shikoku)
• Kisei Line
• Nippo Line (Kyushu)

In later years, operations were restricted to Kyushu and Shikoku, with the remaining locomotives withdrawn in 1983, except for DF50 1, which later passed into JR Shikoku ownership.^[1]

Livery

The locomotives were initially painted in all-over maroon with stainless steel bands, but were subsequently repainted into the standard JNR diesel locomotive livery of vermillion and grey.^[2]

Preserved examples

Three Class DF50 locomotives were preserved.^[3]

• DF50 1: Preserved at The Railway History Park in Saijo, Ehime
• DF50 4: Preserved in a park in Osaka
• DF50 18: Formerly preserved at the Modern Transportation Museum, Osaka, but moved to the Tsuyama Railroad Educational Museum in Tsuyama, Okayama in March 2015^[4]

• 
  Preserved DF50 1 at The Railway History Park in Saijo in May 2015
• 
  Preserved DF50 18 at the Tsuyama Railroad Educational Museum in May 2016

Classification

Main article: Japan Railways locomotive numbering and classification

The DF50 classification for this locomotive type is explained below.

• D: Diesel locomotive
• F: Six driving axles
• 50: Locomotive with maximum speed exceeding 85 km/h