What type of valve should be used for gas service?

The appropriate choice for gas service is a ball or plug valve. These types of valves are specifically designed for use in systems where quick shut-off capabilities and minimal flow resistance are essential.

Ball valves, in particular, offer a spherical disk that allows for smooth operation and can be opened or closed with a simple quarter turn, making them efficient for controlling gas flow. The tight sealing nature of these valves minimizes the potential for leaks, which is crucial for safety in gas applications. Similarly, plug valves operate in a straightforward manner, utilizing a cylindrical plug to regulate the flow and can also provide a reliable seal.

In contrast, while gate valves are suitable for on/off applications, they are not typically recommended for gas service. They can be slow to operate and may not provide the rapid shut-off that is often necessary within gas lines. Butterfly valves, although they can be used in some gas applications, don't create as tight a seal as ball or plug valves, making them less ideal. Check valves are designed to allow flow in one direction and prevent backflow, which is not their intended use in gas service scenarios.

Overall, ball or plug valves stand out as the best choice for gas service due to their functionality, safety features, and efficient flow control.