Gate Valve
A gate valve is a linear-motion isolation valve that opens and closes by raising or lowering a flat or wedge-shaped gate perpendicular to the flow. When fully open, the gate is withdrawn from the flow path, giving a straight-through bore with very low pressure drop. It is designed for fully open or fully closed service and is not suited to throttling, as partial opening causes vibration and seat erosion. Variants include solid, flexible and split wedges, parallel slide and through-conduit slab gates, with rising or non-rising stems. Gate valves are widely used for isolation in water, steam, oil and gas pipelines and process plants. Selection parameters include size, pressure class, body and trim materials, end connections and stem design. Applicable standards include API 600 (steel gate valves), API 602 (compact forged valves), API 6D (pipeline valves) and ASME B16.34.
Examples
- Wedge gate valve for pump suction isolation
- Through-conduit slab gate valve on a piggable pipeline
- Forged steel gate valve on a small-bore steam line