What is the purpose of a pilot line in a pilot-operated valve?

What is the purpose of a pilot line in a pilot-operated valve?

• A. Carries main supply to the actuator
• B. Transmits control signal from the control valve to the main valve to shift its position
• C. Stores compressed air for peak demand
• D. Reduces air humidity

Answer: (B)

The pilot line carries the control signal from the control valve to the main valve’s pilot chamber, so the pressure in that line moves the pilot mechanism and causes the main valve to shift. This setup lets a small, precise control signal move a larger valve, giving fast, reliable actuation with minimal power. It’s not the main supply path to the actuator, which is dedicated to delivering the main pneumatic supply. It’s not a storage reservoir for peak demand, nor a method for reducing air humidity.

The pilot line carries the control signal from the control valve to the main valve’s pilot chamber, so the pressure in that line moves the pilot mechanism and causes the main valve to shift. This setup lets a small, precise control signal move a larger valve, giving fast, reliable actuation with minimal power.

It’s not the main supply path to the actuator, which is dedicated to delivering the main pneumatic supply. It’s not a storage reservoir for peak demand, nor a method for reducing air humidity.