Railways & trains

Trains and railways are one of the most popular and most frequently used means of transport around the world. Whether for local public transport, long-distance journeys or transporting freight – railways are an important part of the transport infrastructure. Functioning valves installed to perform numerous tasks in various different areas are important to guarantee smooth processes in their relevant area of application.

Valves are installed to perform numerous tasks in the railway sector. They can be used to control the filling of wagons with bulk goods, for dosing and shutting off the transport of various different operating materials (e.g. water, sand, etc.) or to support the unloading process.

Steady increases in the number of passengers demonstrate the importance of the railways. If a passenger is asked about their wishes and requirements for a train journey, they will usually answer that they expect to be able to rely on the train to arrive punctually at their destination. However, comfort is also an important aspect that will leave passengers with a positive impression of the train journey.

While the train toilet is probably not the first thing that springs to mind and a functioning toilet is not considered something special from the passenger's point of view, it will quickly attract attention should it stop working. A reliable solution for train toilets – especially controlling the transport of grey & black water using valves – is thus an important issue for railway companies.

Drop chutes were used for the disposal of faecal matter from train toilets for decades, which meant that the waste was deposited directly onto the tracks during travel. Increasing environmental awareness and ever faster trains – on which this type of disposal was no longer feasible for technical reasons – meant that self-contained systems are now used in modern train toilets to collect the faecal matter and grey water on the train.
The black water from the toilet is removed using a vacuum system. Pinch valves from AKO Armaturen control this process and are responsible for stopping and starting the suction.

Another application for pinch valves in the area of rail vehicles is the filling of so-called sand boxes. The sand is used to optimise the braking of the train and to increase traction e.g. on wet rails. The sand from the boxes – loaded beforehand using a filling process controlled via a pinch valve – is spread in front of the wheels on the engine with aid of compressed air or a drop chute. It increases the friction between the wheel and the rail and thus shortens the breaking distance and improves traction.