What type of valve arrangement is typical in a closed-center circuit to control when flow is allowed to the actuator?

• A. A normally open valve
• B. A directional control valve that centers to block flow to the reservoir
• C. A check valve in series with the actuator
• D. A valve that always bypasses to tank

Answer: (B)

In a closed-center circuit you want no flow when the system is idle, so the valve arrangement centers in a position that blocks all paths. A directional control valve that centers to block flow to the actuator (and to the reservoir) achieves this. When the valve is in the center, neither supply nor return lines are connected, so the actuator stays put and pump power isn’t wasted. When you command motion, the valve shifts away from center to connect the pump to the actuator and route flow back to tank, allowing movement. This blocking center design is what makes a circuit truly closed-center, preventing leakage and energy loss in neutral. The other options wouldn’t provide that neutral-blocked state: a normally open valve would allow flow in the center, a simple check valve wouldn’t give controlled bidirectional flow to the actuator, and a valve that always bypasses to tank wastes energy and also fails to keep the actuator isolated in neutral.