Control valve

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Control valves are valves for controlling engines

Control valves in steam engines

In the case of high-performance steam engines , control valves serve as inlet and outlet valves for periodically opening the steam supply line and closing the steam discharge line. Compared to control spools, control valves have smaller dimensions, less harmful spaces and friction losses and can be set separately.

Air brake control valve

Control valves in railroad air brakes control the pressure in the brake cylinder of a vehicle depending on the pressure in the main air line .

The control valve is necessary to enable braking even if the overpressure in the main air line fails. The brake pressure is generated by compressed air stored in an auxiliary air reservoir. While the construction of the control valve of a commercial vehicle is relatively simple, the modern control valve of a railway compressed air brake is more complicated, since the control valve here has to take into account not only the pressure in the brake line and a possible control mechanism for a load-dependent braking force control, but also other elements of the braking force control such as the type of braking and rapid braking acceleration .

Control valves on pipelines

In high-pressure pipelines for the transport of gas or oil, control valve actuators are used in which z. B. the Scotch-Yoke crank mechanism is used.