For controlled shut-off in fluid distribution systems, resilient seated gate valves deliver robust, long-lasting performance through various working conditions. Their design represents an industry-leading standard balancing operator safety and operational reliability.
Construction and Operation
Gate valves feature a wedge-shaped disc operating in a linear motion to open and close flow paths. Resilient seating improves sealing compared to metal-to-metal designs by incorporating an elastomeric “O-ring” around the disc edge. This compresses against the valve body for a drip-tight shut-off unaffected by pipeline irregularities. non rising stem resilient seated gate valve configurations stabilize the handwheel above grade, preventing stress during buried service.
Valve Standards
Gate valves adhere to stringent specifications ensuring interchangeability and quality assurance such as AWWA C509 for buried potable water or AWWA C515 for aboveground service. Compliant valves pass hydrostatic shell testing, seat leakage acceptance, and operational durability verification maintaining drip-tight sealing over millions of cycles. Material certifications and quality programs facilitate compliance.
Suitable Applications
Resilient seated gate valves serve municipal water transmission/distribution alongside mild industrial, commercial and building services applications. Typical uses range from isolating pipelines during maintenance or repairs to throttling flows and controlling system branches. They protect downstream equipment and offer sectionalization in emergencies if locating remotely.
Installation Considerations
Proper gate valve installation factors pipe stresses, substrate, operation loads and accessibility for future exercising or maintenance. Compact joints, thrust blocks and trench design address installation loads. Valves orient to position actuators above grade or indoors while avoiding joints within casing intervals. External coatings and lining suit corrosive contents and environments reaching remote facilities.
Ancillary Features
Handwheels offer leverage for high-torque actuation if pipe diameters exceed 18″. Bypass piping facilitates valve testing or pressure regulation without interruption. Indicators reveal disc position from above grade. Gearing actuators automate large valves. Tapping options facilitate line entry without draining mains. Fire hydrants mount to gate valves supplying emergency flows.
Maintenance Practices
Routine exercising and inspections catch early signs of minor leakage allowing proactive O-ring replacement ahead of failure. Flushing preliminary to repairs removes debris potentially damaging sealing interfaces. Repair “kits” simplify barrier replacements for infrequent shutdowns. Cathodic protection retards corrosion if electrically isolated. Proper handling protects seal materials during joint assembly.
Overall, non-rising stem gate valve deliver highly reliable shut-off backed by robust engineering and extensive use across essential infrastructure worldwide. Standardized construction ensures long-term performance keeping water and other critical infrastructure flowing.