Counter-pressure brake
Encyclopedia
The counter-pressure brake (German: Gegendruckbremse), also named the Riggenbach counter-pressure brake after its inventor, Niklaus Riggenbach
Niklaus Riggenbach
Niklaus Riggenbach was the inventor of the Riggenbach rack system and the counter-pressure brake. He was also an engineer and locomotive builder....

, is a dynamic railway brake on steam locomotives that, through a combination of means, brakes the locomotive in the driving cylinders. In doing so it prevents wear and tear and overheating of the driving wheel
Driving wheel
On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons...

 tyres and brake blocks and enables a continuously high brake force
Brake force
Brake force, also known as Brake Power, is a measure of braking power of a vehicle.In the case of railways, it is important that staff are aware of the brake force of a locomotive so sufficient brake power will be available on trains, particularly heavy freight trains.-External links:*...

 to be applied. The brake works by using the cylinders as air compressors and converting kinetic energy into heat. Steam is emitted during braking but this does not come from the boiler. It is produced by evaporation of water, which is used to cool the cylinders.

Austria and Germany

Counter-pressure brakes were found especially on steam engines that worked long inclines and on rack railway
Rack railway
A rack-and-pinion railway is a railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail...

 locomotives (e.g. on the Vienna Kahlenberg
Kahlenberg
Kahlenberg is a mountain located in the 19th District within Vienna, Austria .-General:Kahlenberg lies in the Wienerwald and is one of the most popular destinations for day-trips from Vienna, offering a view over the entire city. Parts of Lower Austria can also be seen from Stefaniewarte at the...

 Railway (Kahlenbergbahn), relieving brake blocks and tyres from high levels of wear and tear that they would otherwise be subjected to.

For operation on ramps its availability was indispensable because these dynamic brakes on steam locomotives provided the required third independent set of brakes.

A further area of use was in measurement and testing on braking locomotives to provide continuous braking on railway vehicles being tested in normal running. Here a number of steam engines survived in this niche activity in Germany until the middle of the 1970s.

Wales

Counter-pressure brakes are used on the steam locomotives of the Snowdon Mountain Railway
Snowdon Mountain Railway
The Snowdon Mountain Railway is a narrow gauge rack and pinion mountain railway in Gwynedd, north-west Wales. It is a tourist railway that travels for from Llanberis to the summit of Snowdon, the highest peak in England and Wales....

.

Countersteam brake

The counter-pressure brake should not be confused with the countersteam brake
Countersteam brake
A countersteam brake is a brake on a steam locomotive that uses the engine to help brake the locomotive.It uses the working principle of steam cylinders fitted with slide or piston valves such that, by changing the configuration of the valve gear, the motion of the valves is also altered such that...

(German:Gegendampfbremse), which cannot be used as an auxiliary braking system.
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