In a four-port valve, which ports are typically the working ports?

In a four-port valve, which ports are typically the working ports?

• A. A and B
• B. P and T
• C. P and A
• D. T and B

Answer: (A)

In a four-port valve used to control a double-acting cylinder, the ports that actually move air to and from the actuator are the working ports. These two ports connect to opposite ends of the cylinder, allowing one side to receive pressurized air while the other is vented, and then swap roles to reverse motion. They are typically the ones labeled A and B. The other two ports handle supply and exhaust (the pressure source and the exhaust path), but they don’t directly move the load. So the working ports are the two that feed the actuator, i.e., A and B.

In a four-port valve used to control a double-acting cylinder, the ports that actually move air to and from the actuator are the working ports. These two ports connect to opposite ends of the cylinder, allowing one side to receive pressurized air while the other is vented, and then swap roles to reverse motion. They are typically the ones labeled A and B. The other two ports handle supply and exhaust (the pressure source and the exhaust path), but they don’t directly move the load. So the working ports are the two that feed the actuator, i.e., A and B.