title: TU7 diesel locomotive
text: # TU7 diesel locomotive
  
  TU7 (ТУ7) - Soviet, later Russian diesel locomotive for gauge 750 mm (2 ft 5+1⁄2 in) – 1,067 mm (3 ft 6 in).
  
  ## History
  
  The TU7 (ТУ7) was developed in 1971–1972 at the Kambarka Engineering Works to replace the aging locomotive classes TU4 (ТУ4) and TU2 (ТУ2). There were 3,361 locomotives constructed, of which several hundred were exported to the countries of the socialist community and affiliated countries. The TU7 - TU7A (ТУ7 - ТУ7А) was designed to be used on any gauge from 750 mm (2 ft 5+1⁄2 in) to 1,435 mm (4 ft 8+1⁄2 in). In 1986 the locomotive design was updated and designated type TU7A (ТУ7А).
  
  ## D4H
  
  The D4H 1,000 mm (3 ft 3+3⁄8 in) and 9 locomotives D4Hr for standard gauge 1,435 mm (4 ft 8+1⁄2 in), also known as the TU7 - TU7A (ТУ7 - ТУ7А) diesel locomotive, is a series of diesel locomotives currently used on the Vietnamese railway network. With 77 locomotives D4H 1,000 mm (3 ft 3+3⁄8 in) in service throughout the country as of 2005, it is the most common type of locomotive in use in Vietnam. The series was originally procured from the Soviet Union after the Vietnam War.
  
  ## Additional specifications
  
  * Distance between bogies - 4,700 mm (185.04 in)
  * Base of bogies - 1,400 mm (55.12 in)
  * Operating speed - 500 to 1,560 r/min
  * D4H-528, Da Lat–Thap Cham Railway
  * TU7A-3042, Kirov Oblast
  * TU7A-3042, Kirov Oblast
  