What type of valve features a plug running through it?

• A. Globe valve
• B. Butterfly valve
• C. Plug valve
• D. Safety valve

Answer: (C)

The correct choice is based on the design and functionality of the valve types listed. A plug valve is specifically designed with a cylindrical or tapered plug that fits into a valve body. This plug has a hole or port through its center, which aligns with the pipe when the valve is open, allowing fluid to flow through. When turned, the plug rotates to obstruct the flow, providing a simple and effective way to control the flow of liquids or gases in a piping system.

The nature of the plug allows for tight sealing in various operational contexts, making plug valves particularly useful in applications requiring reliable shut-off. Their straightforward design means they can be operated easily, often requiring only a quarter turn to open or close, which can be advantageous in many installations.

In contrast, other options like globe valves feature a movable disk that regulates flow but do not utilize a plug mechanism. Butterfly valves use a rotating disc instead, while safety valves are designed primarily to relieve excess pressure and do not use a plug configuration. Understanding these distinctions is essential for selecting the right valve for specific applications in pipefitting and fluid mechanics.