In pneumatics, what is CV or flow coefficient used for?

• A. To quantify the flow capacity of a valve or orifice and predict airflow
• B. To measure pressure drop
• C. To adjust motor speed
• D. To sense temperature

Answer: (A)

Flow coefficient, CV, is a measure of how much air a valve or orifice can pass for a given pressure difference. This value lets you size components and predict airflow in a pneumatic circuit, which in turn helps estimate actuator speed, response time, and overall performance. In practice, knowing the CV of a valve lets you estimate how much air will flow at the supply pressure and across the valve’s pressure drop, so you can match components to the required airflow. The other ideas—measuring a pressure drop, adjusting motor speed, or sensing temperature—are related to system measurements or control, but they don’t define or quantify the flow capacity of a valve the way CV does.