Gate Valve

A: A solid wedge provides a rigid, one-piece design suitable for most general-purpose liquid and gas applications. A flexible wedge features a circumferential cut that allows the seating faces to adjust slightly to minor body seat angle distortions caused by thermal expansion or pipe stresses, minimizing thermal binding in high-temperature steam services.

A: No. Gate valves are designed exclusively for full open or full closed isolation service. Partial opening exposes the lower edge of the wedge and seat faces to high-velocity fluid erosion, resulting in severe vibration, noise, seat scoring, and premature leakage.

A: OS&Y stands for Outside Screw and Yoke. This design places the stem threads outside the pressure boundary and above the actuator yoke. It prevents process fluid from contacting the threaded stem interface, reduces corrosion and scaling, and provides a clear visual indication of whether the valve is open or closed.

A: Standard construction uses flexible expanded graphite rings surrounded by braided anti-extrusion wiper rings. For strict environmental compliance, valves are supplied with low-emissions packing sets certified to ISO 15848-1 and API 624, limiting stem leakage to under 50 ppmv.

A: Trim selection follows API 600 guidelines based on fluid corrosiveness, temperature, and hardness requirements. For standard hydrocarbon service, Trim 8 (13Cr) is common. For high temperature, corrosive, or erosive services, Trim 5 (Stellite hardfaced) or Trim 12 (Stellite-faced 316) is specified to prevent galling.

A: Each shipment includes EN 10204 3.1 Mill Test Certificates for pressure-containing components, API 598 pressure test reports, General Arrangement (GA) drawings, maintenance manuals, and Certificate of Compliance (CoC) documents mapped to individual valve serial numbers.