A pilot-operated check valve is used on a cylinder to _______.

• A. Increase retract speed
• B. Reduce retract speed
• C. Control tank flow
• D. Hold cylinder in position

Answer: (D)

A pilot-operated check valve behaves like a one-way flow device that can be unlocked by a pilot signal. Placed on a cylinder line, it normally blocks backflow, so hydraulic fluid can’t push the piston back when pressure is removed or when a load tries to move the cylinder. This blocks leakage and external forces from drifting the cylinder, effectively locking it in its current position. When you apply pilot pressure to the valve, it unseats and allows flow, enabling movement in the desired direction. Because it blocks reverse flow unless piloted, its primary role here is to hold the cylinder in position rather than to set retract speed or to control tank flow.