The DF4 is a type of diesel locomotive

Diesel locomotive

A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...

 used in the People's Republic of China

People's Republic of China

China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...

. It has been in production since 1969 and is still produced as of 2007 by several local companies. It is the most common locomotive in China and is used for both passenger and freight services.

DF4

The first DF4 was built in 1969 in Dalian

Dalian

Dalian is a major city and seaport in the south of Liaoning province, Northeast China. It faces Shandong to the south, the Yellow Sea to the east and the Bohai Sea to the west and south. Holding sub-provincial administrative status, Dalian is the southernmost city of Northeast China and China's...

. The first 108 locomotives that were built here are the original DF4s using the 16V240ZJ engine. It took seven years to build all 108 locomotives of this type.

Few of the first series DF4 are still in operation, however the first ever is a permanent exhibition at the Beijing Railway Museum.

DF4A

The DF4A distinguishes itself from first series DF4s with an improved engine, the 16V240ZJA. Production started in 1976 and lasted until 1984.

DF4B (nickname: watermelon, military police)

DF4B are very similar to standard DF4 and DF4A, apart from an improved engine (16V240ZJB). Production started in Dalian in 1984.

DF4C

The DF4C was supposed to replace the DF4B as the main diesel locomotive in China and comes with several improvements, including a new engine revision (16240ZJC). The first DF4C was produced in 1985 and batch production started four years later, in 1989, and lasted until roughly the end of the 20th century.

The DF4C comes in a different color scheme than the previous DF4s, namely dark blue and later light blue and beige.

Gearing variations

The DF4, DF4A, DF4B and DF4C were each produced with two different gear ratios, "passenger" (up to 120 km/h (74.6 mph)) and "freight" (up to 100 km/h (62.1 mph)). The passenger variant was often painted orange.

DF4D (nickname: tiger)

The DF4D, the most recent DF4 revision, has been produced since 1996 with the 16V240ZJD engine. The passenger versions increased top speed to 145 km/h (90.1 mph) or 170 km/h (105.6 mph) for the DF4DK, and a road-switcher version was also introduced.

DF4DJ

The DF4DJ, of which only 2 were built had AC drive technology supplied by Siemens

Siemens

Siemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...

. They were China's first AC drive diesel locomotive.

Manufacturers

DF4s have been manufactured by several companies:

• CSR Sifang Locomotive and Rolling Stock Co., Ltd.
  Sifang Locomotive and Rolling Stock
  CSR Sifang Co Ltd. formerly known as CSR Sifang Locomotive & Rolling Stock Co., Ltd. is a Chinese rolling stock manufacturer based in Qingdao, Shandong province...
  
  
• CSR Ziyang Locomotive Works (DF4B, DF4C & DF4C(A1A))
• Dalian Locomotive & Rolling Stock Works
• Datong locomotive factory
  Datong locomotive factory
  Datong locomotive factory is a Chinese railway locomotive manufacturing plant based in Datong, Shanxi, China, founded 1953. The factory was a major producer of steam locomotives for the Chinese market up to the end of the 1980 when production switched to diesel powered locomotives...