Changeover device for air brakes

from Wikipedia, the free encyclopedia
Representation of the switching device of a passenger coach with positions RIC (P) - R- and R + MG brake addresses
Changeover devices (yellow) of a freight wagon. Above in white letters the type of brake. There is an O erlikon -Bremse with the brake positions G and P . The manual load change is set on the right with the red crank handle.

The changeover device for compressed air brakes is the UIC designation for a component of the compressed air brake on a railway vehicle , which is used to set the different types of braking and the braking behavior of this vehicle.

variants

Depending on the existing positions of the brake, this changeover device is also referred to as changeover device GP or GP change , changeover device GPR or GPR change , changeover device PR or PR change or changeover device PR-MG or PR-MG change , depending on the brake types .

The term "changeover devices for compressed air brakes" also includes the different variants of load changes . These variants of the load change exist not only with the compressed air brake, but also with the suction air brake . Therefore, the different types of load deceleration are not dealt with in this article, but in a separate one. See article load deceleration .

There is still an outdated changeover device for the compressed air brake, this was used to switch on an additional valve for the single brakes. On the one hand, there was the change in release mode . These were used to turn the single-release brake into a multi-release brake by switching on an additional valve. The typical representative was the Rihosek-Leuchter valve , which was used in the Knorr-Bremse and Westinghouse-Bremse (with Rihosek-Leuchter valve type abbreviation K-RL and W-RL ). The second type was the "change of terrain", with which a differently delayed venting of the brake cylinder could be set. Due to the general ban on single-use brakes, these changeover devices are unusual today and are therefore no longer included in international regulations.

Changeover device GP, PR, GPR etc. according to UIC definition

For standard-gauge passenger and freight wagons in Europe, the lever for the device for changing the brake type is standardized by the UIC (passenger cars in the Regolamento Internazionale delle Carrozze (RIC), freight wagons in the General Contract for the Use of Freight Cars (AVV)). According to this standard, the lever has a round knob (ball handle) or a loop (loop handle) and is usually painted yellow. The possible positions are from left to right G, P, R and R + Mg. However, not every vehicle has all these positions, but often only two or three. In the case of passenger cars that can be used internationally and where the passenger train brake complies with the requirements of the RIC regulations, the P position must be provided with a particularly prominent RIC symbol.

In the respective lever position on passenger cars, the information on the braked weight belonging to this position is also attached: in black the pure braking effect of the compressed air brake without additional brake components (such as the brake accelerator), in red the increased braked weight, which also takes these components into account.

In freight wagons, the braked weight does not usually differ between positions G and P, which is why there is no braked weight information directly on the lever of the GP switch. However, depending on the braking position of the train, different percentage deductions are made for the braking percentage. In the case of freight wagons - which today are usually provided with load braking - the brake weights are located when the load is changed manually or - if there are no levers to change the braked weight - near the controls for the brakes on the solebar.

A braking position is prescribed for trains in the book timetable. In braking position G, the changeover device must be brought to position G. If this position is not available on a vehicle (just another type of fast-acting brake), the brake must usually be switched off in accordance with the operating regulations.

Alternative names

  • The term changeover device (s) is used in the Swiss driving regulations .
  • The term brake position change is common on railways in Germany .

Individual evidence

  1. ↑ Archived copy ( Memento of the original from March 4, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. AVV Annex 11 Chapter 4.3 PDF page 41 @1@ 2Template: Webachiv / IABot / www.otif.org
  2. ↑ Wilhelm Hildebrand: The development of the automatic single-chamber air brake on the European main railways. Chapter B, Section III 4, page 131.
  3. ↑ Archived copy ( Memento of the original from March 4, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. AVV Annex 11 Chapter 4.3.2 PDF page 41 @1@ 2Template: Webachiv / IABot / www.otif.org
  4. ↑ RIC Appendix V Chapter 2
  5. ↑ AVV Annex 11 Chapter 4.3 / 4.3.2 / 4.3.3 / 4.3.4 / 4.3.5
  6. ↑ Swiss Driving Regulations (FDV) A2016 Federal Office of Transport (FOT), July 1, 2016 (PDF; 3 MB). R 300.5, Section  3.3  Changeover devices
  7. ^ Jürgen Janicki: Rail Vehicle Technology. Bahn Fachverlag, 2008, ISBN 978-3-980-80025-9 , p. 296 ( limited preview in the Google book search).

Remarks

  1. ↑ The outlawing of single-release brakes was mainly due to the fact that most single-release brakes are designed as single-chamber valves and thus belong to the exhaustible brakes. Because if the time that the valve needs to refill its brake air reserves is not waited between two braking operations, the next braking operation will be weaker. If the brake cylinder is leaking, the brake pressure in the single-chamber brake valves will also drop. This is because the air reserves cannot be replenished with this type of brake valve during braking. These two points are not ideal, especially on long downhill stretches, which normally require several braking operations in quick succession. For this reason, various railway administrations imposed restrictions on the use of more exhaustible types of brake, which could go so far that such wagons were only transported as cable wagons - i.e. with the air brake switched off. The European railway administrations preferred - when they were available - the three-chamber brake valves, which are multi-release and are considered inexhaustible.
  2. ↑ Only permitted for passenger cars (see RIC Appendix V Chapter 2).
  3. ↑ If the position does not correspond to the norm, the color yellow is not permitted. Then the car is usually not transferable. That means: subject to neither the AVV nor the RIC.
  4. ↑ As an example: In Switzerland, the braked weight of the wagons in position G can only be offset against 0.8.