Dividing train

From Wikipedia, the free encyclopedia
(Redirected from Portion working)

Thalys PBA train from Amsterdam Centraal couples with another unit at Brussels-South before continuing to Paris-Nord

A dividing train is a passenger train that separates into two trains partway along its route, so as to serve two destinations. Inversely, two trains from different origins may be coupled together mid-route to reach a common endpoint. Trains on complex routes may divide or couple multiple times. The general term for coupling two or more trains along their shared route sections is portion working.

For example, the westbound Empire Builder travels from Chicago Union Station to Spokane, Washington, where its cars are divided into two trains: one continues to Portland Union Station and one to King Street Station, Seattle. On the eastbound trip, trains from Portland and Seattle are coupled at Spokane before traveling as one train to Chicago.

Dividing trains are useful where line capacity is limited, allowing multiple trains to use the same path over a congested part of a network. The common sections will often be the busiest parts of the routes.


Video: Coupling of two ICE T portions in Leipzig, 2017

On the initial leg of its journey, the train is driven as normal by a single crew. At a designated station before a junction, the train stops and some of the cars are detached, with passengers or goods still on board. The front part of the train then departs to run the remainder of its route. A second train is then formed from the detached cars, the points are changed at the junction, and a new crew drives the train on a different route to a second destination. Where the train is formed of multiple units – self-contained trainsets with their own propulsion and driving cabs – two or more units work in multiple on the first leg. After detachment, the second crew drives in the trailing unit's front cab.

On the return journey, the two trains may join at the same station where they divided. Special signalling is required at the station to allow a following train to enter the block currently occupied by the train in front in order for the two to couple. The British rail network uses a shunt signal to authorize this type of movement.[1]

Possible combinations[edit]

A variety of portion working combinations is possible. For example:

  • Two trains may each depart from separate termini, be coupled together en route, and arrive at their single destination together.
    • Vice versa, a pair of trains may depart together from the same terminus, be separated en route, and then continue to separate destinations.
  • Two trains may each depart from separate termini, be coupled together, and later separated, en route, and then continue to separate destinations.
  • A train may depart from a terminus, be coupled en route to another train departing from the point where the coupling occurs, and then the two trains will continue together to their single destination, thus providing a longer train for a busier portion of the route (or vice versa).
  • A train may depart from a terminus, and divide at a station en route, with both portions then continuing to the same destination, but the first running an express stopping pattern, and the second part stopping more frequently. In the reverse of this, the second portion is the faster of the two, catching up the slow train at the point where they join.


For portion working to be successful, the operator may need to address many issues. For example:

  • Locations for coupling and uncoupling must be designated.
  • The best combinations of services must be carefully considered.
  • Coupling and uncoupling takes time.
  • Portion working can transfer disruption from one section to the wider network.[2]

Dividing trains can sometimes cause issues for unwary travellers, who may board the wrong car and thus arrive at an unexpected destination.[3]




  • IC trains between Genk and Knokke or Blankenberge (IC 1527–1542) used to be divided in Bruges, the front part went to Knokke (IC 1627–1642) while the rest continued to Blankenberge and the same occurred on the return leg (IC 1505–1520). The consists were either made up with AM96 EMU's (enable passage from set coach to another) or M6 coaches hauled by Class 19 locomotives. In the latter case, cab cars and engines are fitted with automatic couplers to allow quick separation. On periods with high affluence or when facing problems, these IC trains could run entirely to one destination (usually Blankenberghe) and another trainset was provided for the leg between Bruges and Knokke. This dual service ended with the new transport timetable introduced in December 2017. Now, separate trains are used for each destination.[4]
  • despite not being advertised as coupling trains, some IC trains between Lille Flandres and Tournai are then coupled with one or two AM96 trainsets going from Tournai or Kortrijk to Namur, therefore allowing to travel directly from Lille to Namur.[5]
  • The same happens with IC trains Between Lille Flandres and Mouscron. At Mouscron, they are coupled with AM96 multiple units which then run IC trains between Mouscron and Antwerp Centraal.[5]


Route[6] From Dividing at Destination
Montreal–Senneterre train Montreal Central Station Hervey-Jonction station Senneterre station
Montreal–Jonquière train Jonquière station


  • There are several dividing regional and high-speed trains all over Germany. ICE trains from Munich often split at Hanover into sections for Bremen and for Hamburg. ICE from Berlin split at Hamm into sections for Cologne and for Düsseldorf.
  • Munich S-Bahn: Line S1 serves both Freising and Munich Airport by splitting at Neufahrn bei Freising station
  • Hanover Stadtbahn: In the evenings and on Sundays the lines 2 and 8 of Hanover's light rail system work with dividing trains. Trains start in Alte Heide as line 2 and divide in Peiner Straße stop. One part continues as line 8 to Messe Nord, the other as line 2 to Rethen. In the other direction, trains reconnect at Bothmerstraße station and run as line 2 to Alte Heide.
  • Hamburg S-Bahn: The trains on the line S1 of Hamburg's S-Bahn system usually split at Ohlsdorf into sections for Hamburg Airport and for Poppenbüttel.
  • Since 2014, the Regional-Express services RE 1 MannheimSaarbrückenTrierKoblenz and RE 11 Luxembourg City–Trier–Koblenz operate jointly with trains dividing in Trier main station. The RE 1 part is operated by the German DB Regio South-West with a Stadler FLIRT single-deck EMU as part of the Süwex network, while the RE 11 part is operated by the Luxembourgish Société Nationale des Chemins de Fer Luxembourgeois with a double-deck Stadler KISS EMU. This is probably the only situation where a single-deck and a double-deck train of two countries' national railways divide
  • Since 2018, the Regional-Express service RE 7 HamburgElmshornNeumünsterKiel/Flensburg is split in Neumünster with the front train continuing to Kiel, the rear to Flensburg.


There are several dividing train services in Japan, and each route has its own name.

Route From Dividing at Destination Remarks
Komachi Tokyo Station Morioka Station Akita Station Shinkansen high-speed train services
Hayabusa Shin-Hakodate-Hokuto Station
Sunrise Izumo Tokyo Station Okayama Station Izumoshi Station Overnight sleeper services
Sunrise Seto Takamatsu Station
Narita Express Narita Airport Tokyo Station Yokohama, Ōfuna Airport rail link
Shinjuku, Ōmiya, Takao

United Kingdom[edit]

The practice of portion working has been followed for a long time on the third rail network of lines in the South East of England, and has been more widely practised in continental Europe.[2] Elsewhere in the United Kingdom, the practice has been less common, because of a general reluctance to design the necessary modern signalling systems, and because of legal constraints on competition between operators.[7]

Dividing trains operate on several lines on the British railway network, commonly (although not exclusively) in the south of the country. To ensure consistent journey times, the front part of a dividing train usually becomes the rear of the returning service when it reunites.

In addition, some services discard carriages part-way along the route, & pick them back up on the return journey. This may be because a portion of the line has short platforms at a number of its stations, or because of demand being much higher on one section than another.

Route From Dividing at Destination Remarks
Arun Valley line[8] London Victoria Crawley or Horsham Front part non-stop to Barnham, then major stations to Portsmouth Harbour or Southampton Central On Sundays calls at all stations to Barnham & divides there.
Rear part most or all stations to Bognor Regis
Caledonian Sleeper[9] (Lowland) London Euston Carstairs Front part to Edinburgh Waverley
Rear part to Glasgow Central
Caledonian Sleeper (Highland) Edinburgh Waverley Front part to Inverness
Middle part to Aberdeen
Rear part to Fort William
Cambrian Coast Line Birmingham New Street Machynlleth Front part to Aberystwyth Both parts call at Dovey Junction, but use separate platforms & therefore must divide one stop earlier.
Rear part to Pwllheli
Caterham line
Tattenham Corner line
London Bridge (some peak-time trains start from Victoria)[10] Purley Front part to Caterham Colloquially known as the "Cat & Tat". Was the most common service pattern on the branches from Purley before resignalling work made them an extension of the Brighton Main Line local tracks.
Rear part to Tattenham Corner
Chatham Main Line[11] London Victoria Faversham Front part to Ramsgate
Rear part to Dover Priory
South West Main Line London Waterloo Southampton Central or Bournemouth Front 5 carriages to Weymouth Most Dorset stations beyond Bournemouth have short platforms, while as far as Poole the front train forms the principal express service on a heavily trafficked line, with the back train operates as a stopping service.
Last 5 carriages to Poole or Bournemouth
Eastleigh Front 5 carriages to Poole Sunday service
Rear 5 carriages to Portsmouth Harbour
West of England Main Line London Waterloo Salisbury Front part to Exeter St Davids
Rear part terminates at Salisbury

United States[edit]

The westbound Lake Shore Limited coupling process at Albany–Rensselaer.
The River Cities consisted of a single coach conveyed between the Mules at St. Louis and the City of New Orleans at Carbondale.
The Houston and Laredo sections of the Inter-American assembling at Temple.
Amtrak routes
Route From Dividing at Destination Remarks
Empire Builder Chicago Spokane Seattle
Lake Shore Limited Chicago Albany–Rensselaer Boston South Station
New York
Texas Eagle Los Angeles San Antonio Chicago The division occurs only for the Sunset Limited's three weekly round trips. The Texas Eagle runs an additional four round trips per week between San Antonio and Chicago alone.
Sunset Limited New Orleans
Former Amtrak routes
James Whitcomb Riley Chicago Charlottesville Washington, D.C. 1971–1976
Newport News
Floridian Chicago Jacksonville St. Petersburg 1971–1979
National Limited Kansas City Harrisburg (pre-1978); Philadelphia (post-1978) New York 1971–1979
Washington, D.C.
Lone Star Chicago Fort Worth Dallas 1975–1976, 1977–1979
Inter-American Chicago Temple Houston 1979–1981
Pioneer Chicago Ogden; Denver (post-1991) Seattle 1980–1997
San Francisco Zephyr and California Zephyr Oakland
Desert Wind Los Angeles
River Cities New Orleans Carbondale Kansas City 1984–1993
City of New Orleans Chicago
Gulf Breeze New York Birmingham Mobile 1989–1995
Crescent New Orleans

See also[edit]


  1. ^ Richard Stokes (executive producer); David Dore (writer, narrator) (1989). British Rail signalling: part 1 (video). British Railways Board. Event occurs at 20:37. Retrieved 26 August 2013.
  2. ^ a b "Further written evidence from Jonathan Tyler, Passenger Transport Networks (HSR 138A)". House of Commons. Retrieved 15 February 2013.
  3. ^ Christian, Maxwell (May 2012). "The Colonel's Extracts: The Pain of the Dividing Train". Retrieved 26 August 2013.
  4. ^ "Plan de transport de décembre 2017 : Flandre occidentale". belgianrail.be (in French). Retrieved 11 June 2017.
  5. ^ a b "BeLuxTrains en français".
  6. ^ "VIA Rail Remote Services Timetables" (PDF). railpassengers.org. Rail Passengers Association. 7 July 2023. Retrieved 8 April 2024.
  7. ^ "The Potential for Increased On-Rail Competition" (PDF). Renaissance Trains/Office of Rail Regulation UK. Archived from the original (PDF) on 5 September 2012. Retrieved 15 February 2013.
  8. ^ https://www.southernrailway.com/travel-information/plan-your-journey/timetables, see Table 28
  9. ^ "Caledonian Sleeper timetables & tickets" (PDF). First ScotRail. 9 December 2012. Retrieved 26 August 2013. {{cite journal}}: Cite journal requires |journal= (help)[permanent dead link]
  10. ^ https://www.southernrailway.com/travel-information/plan-your-journey/timetables, see Table 38
  11. ^ "Mainline train times 3: Kent Mainline via Chatham". Southeastern. 19 May 2013. Archived from the original on 23 June 2013. Retrieved 26 August 2013. {{cite journal}}: Cite journal requires |journal= (help)