Follow-up train operation
As Folgezugbetrieb or Zugfolgebetrieb is called the trip not interconnected train units, each with its own drive ( railcars ) mutual vision distance. They operate under a common train number. However, the railway or tram route is not suitable for the correspondingly longer train .
In the past, this type of operation was often found in interurban trams and is still used today in many rack- and- pinion railways , such as the Bavarian Zugspitzbahn . Sufficiently long crossing tracks , sufficiently effective brakes to be able to come to a stop within the viewing distance, and visibility conditions that allow the minimum distances to be kept are required.
In Switzerland, trains running in sequence are referred to as a train set .
Operational flow
In the case of follow-up train operations, two or more courses or circuits , for example a standard car and an emergency car or double car, share a timetable and follow each other within sight . Oncoming journeys have to wait at the crossing points until all trains have arrived. Sometimes the relief train is sent ahead of the regular train, which is referred to as a preference . Advantages and subsequent moves are called supplement moves. If the usable length of the crossing tracks is not dimensioned for subsequent train operations, subsequent trains can only run in one direction of travel. In this way, a higher capacity can be offered without having to adapt the infrastructure, for example during rush hour or during major events.
In Switzerland, the following minimum distances apply between the partial trains on the route:
| Maximum line speed | Minimum distance |
|---|---|
| up to and including 12 km / h | 50 meters |
| up to and including 28 km / h | 100 meters |
| up to and including 40 km / h | 200 metres |
Securing train journeys
The follow-up train operation knows two different types of operation. On the one hand, the type of operation with specially signaled trains that indicate to the staff of the oncoming trains that there are still trains to follow, for example on the Pilatusbahn . On the other hand, there is security by means of a route block , in which automatic track vacancy detection systems ensure that a route section is only released when all subsequent trains have arrived.
Signaling
If the signaling is carried out by a board, the next train operation is indicated to the staff of the oncoming journeys by a special signal board on the first and the following trains. Only the last vehicle of such a column - also called a train group - is not marked.
In the past, it was common practice for trams in Vienna to run the privileges without a line number - that is, with a white signal disc instead of the usual white line number on a black background. In contrast, the Pöstlingbergbahn in Linz and the Thuringian Forest Railway used circular red discs with a white border as a sign of the next train operation. In Switzerland, on routes without a route block, follow-up trains are signaled with a green and white disc or at night with a green light. Often round green signal disks with a white diagonal bar are used; now and then, elongated signal disks with white and green diagonal bars are used. The Schynige Platte Railway signals at the end of the train, the Pilatus Railway at the Zugspitze. The Bayerische Zugspitzbahn uses white, circular signal discs with black capital letters. The first train carries the letter C, the second train the letter B and the last train the letter A. Only when train A has entered, trains traveling in the opposite direction may leave the crossing station.
In the German signal order for trams ( SOStrab ), a plant of the tram construction and operating regulations (BOStrab) exists for the Folgezugbetrieb a rectangular marker board with the changing over the years designations St 30, Zg 2 or Zg 5. It is reunification signal or called trailing marks . This is a green triangle on a yellow background. In the 1958 edition it says:
“The signal shows the driver of a counter train that another train is following the one carrying this signal. The signal is to be attached to the front of a train in such a way that it can be clearly recognized by the driver of the opposite train before the encounter. "
As a special feature, the Neuchâtel tram used, in addition to the actual next train board, a crossed line number as a supplementary identifier for a previous train - that is, the black line number was also highlighted in green and crossed out with a white diagonal bar. However, this variant was only found in the four articulated railcars with road numbers 1101 to 1104 that were taken over from Genoa in 1962 .
The follow-up signal of the German SO Strab
Tram Woltersdorf : overtravel signal to a special car
Pöstlingbergbahn, the red disc with a white border indicates a next train
Locomotives of the Schynige Platte Railway with different train boards on June 29, 2008 in Wilderswil, Switzerland
Zugspitzbahn: the illuminated A shows oncoming traffic that it is the last of up to three trains and that no further trains are coming
In this former Basel railcar, the small green light on the far right served as a follow-up train signal at night
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Block fuse
With the possibility of driving at higher speeds on rack and pinion routes (the maximum today is 40 km / h) and because of the increasing traffic, individual rack and pinion railways were used to secure the single-track routes by means of route blocks . At the same time, the follow-up train operation had to be maintained because the train length in rack and pinion operation is limited depending on the incline, in particular because of the safety during rapid braking. The safety systems of such railways, for example the Wengernalp Railway , are designed in such a way that several trains can travel freely in one direction. When leaving a train station, an automatic track vacancy detection system records the occupancy or the total number of axles of all subsequent trains, usually on an axle counting basis in newer systems . The exit signals can also be placed on the occupied track if the permit is available. The next train is shown a special signal image for a follow-up journey at the exit signal. There is no signaling of the permitted speed, all routes are displayed with driving term 1 . Follow-up trips are signaled based on the busy signal with a horizontal, orange bar that is integrated in the main signal .
| Main signal | meaning |
|---|---|
|
Driving term 1 on type L signal for follow-up train operations on the Wengernalp Railway |
|
Signal image for following another vehicle , inspired by the busy signal |
|
Signal pattern stop on signal type L for train operation |
The clearing section of the main line ends in front of the entry point of the next station. Only when the total number of axles retracted matches the number that left the previous station or the entire section of the route reports the unoccupied state, the permit can be changed and the route released for trains in the opposite direction. This means that there is no need to signal subsequent trains on the trains themselves.
See also
Web links
Individual evidence
- ↑ a b c d e Swiss Driving Regulations (FDV) A2016 Federal Office of Transport (FOT), July 1, 2016 (PDF; 3 MB). R 300.15, section 2 train formation
- ^ Die Schiene , Volume 33, Number 12, December 2007, page 15
- ^ Signal regulation for trams from 1958, page 19
- ^ Hans Schlunegger: New interlocking systems on the Grindelwald - Kleine Scheidegg route of the Wengernalp Railway (WAB) . In: Schweizer Eisenbahn-Revue 2/2004, Luzern, Minirex, ISSN 1022-7113