Gate Valve

Gate valves are widely used in industrial piping systems for on/off service where a straight-line flow with minimum restriction is required, such as in oil, gas, water, and chemical plants. They are specified by nominal size, pressure rating, end connections, and body/bonnet material. Grades are distinguished by the gate design (solid wedge, flexible wedge, or split wedge), trim material, and compliance with standards like API 600 or BS 1873. They are not suitable for throttling or frequent operation, as partial opening can cause vibration and damage to the gate and seat.

This directory entry provides reference data for gate valves as a product category. The listed parameters—such as nominal size DN15–DN600, pressure rating PN16–PN40, temperature range -29 to 425 °C, and materials like WCB, CF8M, 1.4408, brass, and ductile iron—are typical ranges and must be verified for the specific model and application. Standards such as ASME B16.34, API 600, BS 1873, EN 1984, and GB/T 12234 serve as procurement and verification references, not as proof of certification or compliance for any particular product.

When selecting a gate valve, confirm the required nominal size, pressure class, end connections (flanged, butt-weld, socket-weld), body and trim materials, and actuation type (handwheel, gear, electric, pneumatic). Verify the face-to-face dimension per ASME B16.10, leakage rate per API 598, and shell test pressure (1.5 × rated pressure). The Cv value (50–5000 US gal/min) and stem diameter (20–100 mm) are indicative and depend on size and pressure class.

Maintenance signals include leakage through the valve when closed, difficulty in operation, or visible damage to the gate or seat. Failure boundaries include use for throttling, frequent cycling, or operation beyond the rated pressure or temperature. Always consult the legal manufacturer or supplier to confirm model-specific values and standards.

The valve operates by raising or lowering a gate perpendicular to the flow path. When fully open, the gate is completely withdrawn from the flow, creating a full-bore passage with negligible pressure drop. When closed, the gate seats against two seat rings to provide a tight seal. The gate is actuated by a threaded stem, which is turned by a handwheel or actuator, converting rotary motion into linear motion.