Which valve uses a flat circular plate that rotates 90 degrees across the pipe to control flow?

Which valve uses a flat circular plate that rotates 90 degrees across the pipe to control flow?

• A. Gate Valve
• B. Butterfly Valve
• C. Pitot Tube
• D. Static Pressure

Answer: (B)

A flat circular plate that turns a quarter turn to control flow is the hallmark of a butterfly valve. The disc is mounted on a stem and rotates 90 degrees to open or close the passage: when the disc is parallel to the flow, the valve is open; when rotated so it blocks the pipe, the valve is closed. This design is compact, quick to operate, and offers low resistance when open. A gate valve achieves shutoff by moving a gate up and down, not by rotating a disc. A pitot tube is an instrument used to measure fluid velocity, not to regulate flow. Static pressure is simply the pressure in the fluid without considering flow, not a valve. Hence, the butterfly valve fits the description.

A flat circular plate that turns a quarter turn to control flow is the hallmark of a butterfly valve. The disc is mounted on a stem and rotates 90 degrees to open or close the passage: when the disc is parallel to the flow, the valve is open; when rotated so it blocks the pipe, the valve is closed. This design is compact, quick to operate, and offers low resistance when open. A gate valve achieves shutoff by moving a gate up and down, not by rotating a disc. A pitot tube is an instrument used to measure fluid velocity, not to regulate flow. Static pressure is simply the pressure in the fluid without considering flow, not a valve. Hence, the butterfly valve fits the description.