Which valve type is typically used for on/off service in a pipeline?

The gate valve is commonly used for on/off service in a pipeline due to its design that provides a straight flow path and minimal resistance when fully opened. This allows for efficient flow regulation and ensures that when the valve is closed, it creates a tight seal, preventing the passage of liquid. The gate valve operates by raising or lowering a gate or wedge within the valve body, which can swiftly transition between fully open and fully closed positions. This characteristic makes it ideal for situations where the fluid flow needs to be completely stopped or allowed without causing pressure changes that might disrupt the system's performance.

In contrast, other valve types serve different purposes. Globe valves are typically used for throttle control and fine adjustments in flow rather than complete shut-off. Check valves allow fluid to flow in only one direction and are designed to prevent backflow, not for on/off service. Needle valves provide precise flow control but are not intended for quick shut-off applications; they are used for small flow rates. Thus, the gate valve stands out as the preferred choice for simple on/off operation in water distribution systems.