Wastewater New York State Practice Exam

What type of valve consists of a disk that rotates about a spindle and is parallel to the axis of the conduit when fully open?

1. Gate valve

2. Check valve

3. Ball valve

4. Butterfly valve

The correct answer is: Butterfly valve

The correct choice is a butterfly valve. This type of valve is characterized by a disk that rotates around a spindle and remains parallel to the flow of fluid when fully open. This design allows for quick operation, requiring only a quarter turn to move from fully closed to fully open, providing effective flow control with minimal pressure drop across the valve. Butterfly valves are often used in situations where space is limited or where a lightweight yet effective flow control mechanism is required. They are particularly advantageous in larger pipe systems and can handle a wide range of fluids. Understanding the characteristics of butterfly valves is crucial for wastewater management, where controlling flow rates and minimizing energy consumption are critical factors in system design and operation. Recognizing how these valves function helps in selecting the appropriate valve type for various applications in wastewater treatment processes.