Gate Valves

A gate valve is a type of slide valve that uses a flat or curved disc perpendicular to the process flow. The disc slides into the flow stream to provide shut-off. The fluid pressure acting on the disc is sufficient to produce a satisfactory seal between metal-to-metal seatings.

The surfaces of the disc in contact with the guides and the leading edge are coated with a cobalt-based material applied through a plasma transfer arc process. This coating reduces erosion caused by suspended particles transported by the fluid.

One advantage of gate valves is their low resistance to flow, which minimizes pressure drop across the valve.

Gate valves can be used in liquid or gas services to isolate the downstream line from the upstream. Typical applications are in CO boiler outlet lines, expander outlet and electrostatic precipitator lines. They can handle either fluid or gas carrying solids in suspension.

The body of the valve is usually made of SA 516 Gr70 carbon steel (lined with refractory material, in the cold wall design) or 304H stainless steel (for hot wall conditions). Gate valves are capable of operating at temperatures up to 950 °C. Valve internals, disc guides and stem are typically made of SA 240 Tp 304 H stainless steel. Remosa however will meet any customer request for different body and internal materials.

Gate valves can use an electric, hydraulic or pneumatic actuator and they are supplied complete of a purging system to prevent any solid materials build-up.