Railway ferry
Railway ferries (also called railway ferries or trajectory ships ) are ships designed for the transport of railway wagons on railway ferry connections . Depending on the design and use of the ship, passengers and passenger cars, freight cars or, in some cases, additional motor vehicles are transported. The term railway ferry is also used as a synonym for the railway ferry connection or railway ferry line as such.
History and technical details
Structural development
The railway ferry defines itself as a shipbuilding type through its construction for the transport of railway wagons, which are loaded and unloaded rolling on their own wheels .
The first ship used as a rail ferry was used by the Monkland and Kirkintilloch Railway in 1833 to transport coal wagons on the Forth and Clyde Canal . Three years later, in April 1836, the Susquehanna, the first US rail ferry, began its service between Havre de Grace and Perryville on the Susquehanna River .
The first modern rail ferry was the Leviathan , a paddle wheel steamer , which was constructed in 1849/50 by the engineer Thomas Grainger for a ferry line of the Edinburgh, Perth and Dundee Railway . The ship began operating between Granton and Burntisland across the Firth of Forth on February 3, 1850. Since then, the development of the railway ferries has followed, on the one hand, the further development of general shipbuilding, such as the change in shipbuilding material from wood to iron to steel, and also developed its own typical distinguishing features.
The Leviathan was already a double-ended ship that made it unnecessary to turn the ship during docking maneuvers. It had a fore and aft rudder and a loading ramp designed by Thomas Bouch , which worked with an inclined plane to compensate for the difference in tides. The bridge consisted of a midships between the two Schaufelradkästen mounted walkway with steering position. Later double-ended ferries received bridges at both ends of the ship. The majority of today's rail ferries are designed as double-ended ferries due to the faster handling rates. In particular, such rail ferries, which are used on longer connections across the open sea or in particularly rough sea areas, are, however, often built as larger single-end ferries with a stern ramp. In contrast to ferries for motor vehicles, rail end ferries generally have an additional rear bridge because of the required accuracy when entering the ferry bed.
The capacity of the rail ferries has been increased over time by several developments, depending on the volume of traffic and the length of the ferry line to be used. On the one hand, the ships as such have become larger, and on the other, rail ferries can be built with one or more rolling decks and one or more parallel tracks per deck.
The Leviathan had three parallel tracks. Smaller ships, especially on short routes, were also built with one or two parallel tracks. Later ferries usually had three or four parallel tracks. The Trelleborg , which was put into service in 1982, was the first ship with five parallel tracks. Today's two- and three-deck ferries often have five parallel tracks with a length of up to 1100 meters.
The first rail ferries still resembled flat prehouses , on whose upper deck the wagons were pulled. Ferries with two decks were later developed, the loading of which required appropriate ramps (as port facilities or on board). In addition, sea-going multi-deck ferries have bow or stern flaps for sea-proof locking of the corresponding roll deck. In 1975, Railship I, the first ship with three roll decks, went into operation. Two more roughly identical ships followed. The specialty of these three ships was the loading via only one five-track stern ramp, the distribution of the wagons within the ship was done by means of a double elevator. There are also ferries with two roller decks and a ramp for loading the weather deck . As a result of the strong growth in car traffic, more and more ferries have also been equipped with loading decks for motor vehicles since the 1950s.
Railway ferries require a much closer adaptation to the land facilities than does ferries for road vehicles. On the one hand, the ferry bridges on railway ferry connections are usually land-based, they are placed on the ship. The gauges on land and on the loading deck must match. In addition, the running edges of the tracks must match each other with only minor deviations in the single-digit millimeter range. The bend angles of the ferry bridge must also adhere to tight tolerances. Railway ferry bridges are therefore usually significantly longer than ferry operations for road vehicles and often consist of several parts. The required fit and track position mean that rail ferries can usually not be used on several routes.
In some countries, such as Denmark or Sweden, the transitions have been standardized nationally. This includes not only the recordings for the ferry bridge and the track layout, but also the width of the ship. An example of a ferry designed for several sea routes was the Warnemünde motor ferry of the Deutsche Reichsbahn from 1963. With the extendable rubbing strips aft on the starboard side, several ferry beds of different widths could be approached via the stern.
drive
A distinction is made between non-powered and self-propelled rail ferries.
Driveless railroad barges, barges or trajectory barges can be found mainly on protected or closed waters. However, there are also isolated, sea-going, non-powered rail barges. What they all have in common is that they are moved by tugs or push boats . Chain or rope-driven ferries form a kind of hybrid, the path of which is determined by the chain or rope on which they move between two ferry points.
The majority of the railway ferries have their own drive. Due to the special requirements in terms of maneuverability, there have been some special ways in the development of the railway ferry drives. The first self-propelled railway ferries were side- paddle steamers . In contrast to conventional steamers of this type, their drive to improve maneuverability when turning and berthing often consisted of two independently controllable steam engines , each acting on one of the paddle wheels.
The introduction of the diesel engine as a prime mover was delayed for the railway ferries because various disadvantages of the diesel engine had to be overcome. This included their low torque at low speeds and the necessity of frequent stopping and reversing to change direction during the mooring and casting off maneuvers - associated with loss of time to transfer commands. In addition, a ferry drive often has to be operated in different speed levels - which are unfavorable for the diesel engine. Solutions to these problems resulted from the use of multi-step gearboxes with clutches, the installation of controllable pitch propellers and diesel-electric drive systems .
Maneuvering devices
Even the early railway ferry Leviathan was able to support its maneuvers with rudders at the bow and stern, a characteristic that almost all double-ended ferries have to this day. Other means introduced in the course of the development to improve the necessary maneuverability are propulsion systems with several independently controllable propellers , the installation of bow and stern thrusters or drives with Schottel rudder propellers and Voith-Schneider propulsion .
gallery
German special postage stamp for 100 years of Sassnitz – Trelleborg
Mississippi River Ferry circa 1920
Railway ferry in China with apron and bridge
ICE unloading in Puttgarden
Others
The Bodensee-Trajekte were before the completion of the railway lines Stahringen-Friedrichshafen and Friedrichshafen-Lindau significant because the rail networks of Baden, Württemberg and Bavaria were previously connected only over Lake Constance. There is a ferry to the railway across Lake Hallstatt . The Hallstatt train station of the Salzkammergutbahn (from 1877) is located on the opposite east bank of the lake, about 1 km away. A shipping line provides the connection to the city of Hallstatt on the west bank for people and formerly the post office. In particularly cold winters, a snowmobile replaced the ice.
literature
- Arnulf Hader, Günther Meier (ed.): Railway ferries of the world: From the traject to the three-deck ferry . Koehlers Verlagsgesellschaft, Herford 1986, ISBN 3-7822-0393-3 .
- Alfred Dudzus, Alfred Köpcke: The great book of ship types . Weltbild, Augsburg 1995, ISBN 3-89350-831-7 .
- Hans Schlieper: Railway trajectories across the Rhine and Lake Constance. Alba, Düsseldorf 2009, ISBN 978-3-87094-369-1 .
Web links
Individual evidence
- ^ Wayne K. Talley: The Blackwell Companion to Maritime Economics . Volume 11. John Wiley & Sons / Blackwell Publishing, Chichester / Malden 2012, ISBN 978-1-4443-3024-3 , pp. 163 .