What is the primary function of a meter-out flow-control valve in a hydraulic system?

The primary function of a meter-out flow-control valve in a hydraulic system is to regulate fluid flow. This type of valve is specifically designed to control the speed of an actuator, such as a cylinder or motor, by adjusting the amount of fluid that exits the actuator. By restricting the flow of fluid leaving the actuator, the meter-out valve can effectively manage the speed at which the actuator operates, providing smooth operation and precise control.

In hydraulic systems, controlling fluid flow is essential for maintaining consistent performance and preventing abrupt movements, which can lead to mechanical stress or failure. The meter-out flow-control valve is often used to enhance the speed control of hydraulic cylinders, especially in applications where the load may vary or where a gradual movement is necessary.

Other functions mentioned in the options—such as increasing fluid pressure, providing shock absorption, or changing the direction of flow—are distinct from the specific role of a meter-out flow-control valve. Increasing fluid pressure is typically managed by pumps or pressure-relief valves. Shock absorption is associated with devices designed to cushion impacts, and changing the direction of flow would be the role of directional control valves. Thus, the meter-out flow-control valve's unique capability to regulate fluid flow is what defines its primary function in the system.