Regulating the flow rate affects the speed of the actuator. This makes it possible to achieve two goals. The first of them controls this speed, while the second sets the speed at the desired level. If the actuator is to move with a variable, adjustable speed, it is enough to use a throttle valve. However, if this speed is to be set at a given level and at the same time this speed is to be independent of disturbances, a flow control valve should be used. The group of flow control valves also includes differential lock valves and flow dividers (synchronisers).