In a cylinder circuit, when the pilot signal is removed, the pilot-operated check valve _______.

• A. Opens to allow free flow
• B. Closes to hold the load in position
• C. Increases system pressure
• D. Diverts flow to tank

Answer: (B)

Pilot-operated check valves provide a one-way lock: they open to allow flow when a pilot signal is present, and when that signal is removed, the valve closes and blocks backflow. In a cylinder circuit this means the actuator is allowed to move only while the pilot is energized, and once the pilot pressure is gone, the valve returns to the closed position, trapping pressure on the load side and holding the load in its current position. This prevents drift due to leakage and keeps the cylinder locked when no command is active. It doesn’t free-flow, increase system pressure, or divert flow to tank—those functions would come from different valve actions.