Which statement is true about flow in a closed-center system when not commanded?

Which statement is true about flow in a closed-center system when not commanded?

• A. Flow is unimpeded to the actuator
• B. Flow to the reservoir is blocked; pressure remains in the lines
• C. Flow is directed to a cooling loop
• D. Flow is vented to atmosphere

Answer: (B)

In a closed-center hydraulic system, when there is no command, the valve centers and blocks the path to the actuators. The pump continues to push fluid, but with the center position there’s no outlet for that flow toward the work ports, so the flow is effectively blocked and the fluid is held in the lines. As a result, pressure remains in the circuit until the relief valve opens to dump excess fluid back to the reservoir. This is why the statement that flow to the reservoir is blocked and pressure stays in the lines best describes the situation.

In a closed-center hydraulic system, when there is no command, the valve centers and blocks the path to the actuators. The pump continues to push fluid, but with the center position there’s no outlet for that flow toward the work ports, so the flow is effectively blocked and the fluid is held in the lines. As a result, pressure remains in the circuit until the relief valve opens to dump excess fluid back to the reservoir. This is why the statement that flow to the reservoir is blocked and pressure stays in the lines best describes the situation.