Non-return valves

Non-return valves belong to the category of industrial valves. These prevent a medium from flowing back. It opens, when a medium flows in the direction it is supposed to, and closes, to prevent the medium from flowing in the unwanted direction. For example, a compressed-air container is equipped with a non-return valve to ensure that the compressed air remains in the container, rather than flowing back into the compressor once it has been shut down.