Which of the following types of valves is designed for on/off service?

The gate valve is specifically designed for applications requiring full flow and minimal resistance in the pipeline, making it ideal for on/off service. When fully opened, the gate allows fluid to flow freely through the valve with very little pressure drop, which is essential for systems where maximum flow is required.

In the case of on/off service, the gate valve provides a physical barrier that can be raised or lowered to control the flow. When the gate is closed, it seals tightly against the valve seat, preventing any fluid from passing through. This makes it particularly effective for applications where the valve will either be fully open or fully closed, rather than modulating flow.

While other types of valves like ball valves can also be used for on/off service due to their quick operation and good sealing properties, gate valves are traditionally preferred in larger pipes and systems where flow control is primarily binary (either fully on or fully off).