Buffer stop

For other uses, see Bumper.
Two views of a Hayes-built bumper at the Linden Railroad Museum, Linden, Indiana. This design accommodates the AAR coupler.
Energy-absorbing buffer stop in France
This buffer stop is designed to move up to 7 metres (23 ft) to slow down a 850-tonne (840-long-ton; 940-short-ton) passenger train from 15 km/h (9.3 mph) without damaging the train or injuring passengers.
A buffer stop or sand drag on the Montreal Metro

A buffer stop or bumper (US) is a device to prevent railway vehicles from going past the end of a physical section of track.

The design of the buffer stop is dependent, in part, on the kind of couplings that the railway uses, since the coupling gear is the first part of the vehicle that the buffer stop touches. The term "buffer stop" is of British origin, since railways in Great Britain principally use buffer-and-screw couplings between vehicles.


Several different types of buffer stop have been developed. They differ depending on the type of coupler used and on the intended application.

If there is extra room behind the bumper block, there is usually a sand or ballast drag that is designed to further retard a runaway train. One such accident occurred when a Northern Line train powered past the bumper block at Moorgate station in 1975 on the London Underground system.


Largely because of its mass, a train transfers an enormous amount of kinetic energy in a collision with a buffer stop. Rigid buffers can only safely cope with very low-speed impacts (i.e., nearly stationary). To improve stopping performance, a way of dissipating this energy is needed, through compression or friction. Following a buffer stop accident at Frankfurt am Main in 1902, the Rawie company developed a large range of energy-absorbing buffer stops. Similar hydraulic buffer stops were developed by Ransomes & Rapier in the UK.

Dowty retarders

Dowty retarders

When it is desired to slow or stop moving trains, without erecting a solid buffer stop, dowty retarders may be employed. They press upwards against the wheels, and may optionally be turned off as required.


Wheel stop

Wheel stops are used to stop slow moving trains from continuing down a level track section.


The aftermath of the Gare Montparnasse accident

See also


  1. "Infrastructure (Iran)". Railway Gazette International. 1/2009: 16. January 2009.
  2. "Framework". Los Angeles Times.
  3. "A Csepeli Hév fekete áprilisa – 33 éve történt a tragikus HÉV baleset". Retrieved 11 November 2012.
  4. Chow, Vincent. "Derailment of Malaysia LRT". Vincent Chow dot Net. Retrieved 14 December 2011.
  5. http://www.jutarnji.hr/vlak-na-kolodvoru-udario-u--odbojnik--vise-od-50-ozlijedenih-/418298/
  6. "Two hurt as maintenance train ploughs through shop". DutchNews.nl. 26 July 2010. Retrieved 14 December 2011.
  7. http://sverigesradio.se/sida/artikel.aspx?programid=2054&artikel=4270024
  8. Keeling, Brock (2 March 2011). "Accident at 4th & King Caltrain Station Sends Passengers to Hospital". sfist.com. Retrieved 14 December 2011.
  9. Fenton, Reuven (8 May 2011). "Dozens hurt after PATH train crashes into Hoboken platform". New York Post. Retrieved 14 December 2011.
  10. Cowan, Alison Leigh (8 May 2011). "Dozens Injured as Train Crashes in New Jersey". The New York Times. Retrieved 14 December 2011.
  11. "Argentine train crash kills 49 people, hurts 600". Yahoo.com. 22 February 2012. Retrieved 22 February 2012.
  12. "Stockholm train crashed into apartments 'by cleaner'". BBC News. January 15, 2013.
  13. "Collision between passenger train and platform at Cleveland, Qld, 31 January 2013".
  14. "Passengers 'jolted' after train collision". Fairfax NZ. April 15, 2013.
  15. "Passenger taken to hospital after Chester collision". RailNews. 20 November 2013. Retrieved 22 November 2013.
  16. "Train crashes into Chester Station barrier". BBC News. BBC. 20 November 2013. Retrieved 22 November 2013.
  17. Esposito, Stefano; Rossi, Rosalind; Owen, Jordan; Slefo, George P. "Blue Line train derails at O'Hare, climbs up escalator; 32 hurt". Chicago Sun Times. Retrieved March 24, 2014.
  18. Mahesh, Niha. "32 Die as Train Derails Near Rae Bareli in Uttar Pradesh, 50 People Injured". NDTV India. Retrieved 20 March 2015.
  19. Srivastava, Piyush (22 March 2015). "UP train crash death toll rises to 58 as driver reveals his SOS alerts were ignored". London: Mail Online. Retrieved 22 March 2015.
  20. "1 injured as metro train crashes near Abbaseya station". Daily News Egypt. 26 April 2015. Retrieved 26 April 2015.
  21. "Egypt's underground metro goes off rail, crashes in wall". Ahram Online. Al-Ahram. 26 April 2015. Retrieved 26 April 2015.
  22. http://www.bbc.co.uk/news/uk-england-london-34283057
  23. http://nwt.se/karlstad/2016/04/09/olycka-pa-centralstationen
Wikimedia Commons has media related to Buffers.
This article is issued from Wikipedia - version of the 11/10/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.