The ductile iron flanged gate valve (resilient seated gate valve) provides reliable isolation and flow control for municipal water distribution networks, wastewater treatment plants, and industrial piping systems. Engineered with a durable ductile iron body and an EPDM/NBR encapsulated wedge, it achieves bubble-tight shutoff (Zero Leakage, Rate A per ISO 5208) and withstands rigorous pipeline stress and hydraulic fluctuations.
Size Range: DN50 - DN1200 (2 inches - 48 inches)
Pressure Ratings: PN10, PN16, PN25 / Class 125, Class 150
Design Standards: EN 1074-2, EN 1171, AWWA C515, ISO 5259
Flange Drilling Options: EN 1092-2 (ISO 7005-2), ASME B16.42, AS 2129
Technical Specifications
|
Parameter |
Specification Details |
|
Body & Bonnet |
Ductile Iron GGG50 (ASTM A536 65-45-12) |
|
Wedge |
Ductile Iron fully encapsulated with high-grade EPDM / NBR |
|
Stem |
Rolled-thread Stainless Steel 420 (AISI 420) or SS316 for high tensile strength |
|
Stem Nut |
Brass (CuZn35Pb2) or Aluminum Bronze |
|
Gaskets & O-Rings |
EPDM / NBR (Resistant to aging and permanent deformation) |
|
Coating |
Internally and externally Fusion Bonded Epoxy (FBE), min. thickness 250 micrometers |
|
Operation |
Handwheel, Industrial Gearbox (ISO 5210 top flange for electric actuators), Square Cap |
Key Features
Non-Rising Stem Design: Minimizes operating clearance requirements and protects internal stem threads from external grit and soil burial in underground installations.
Full Flow Bore: Straight-through, unobstructed waterway completely eliminates pressure drop and prevents debris accumulation.
Triple O-Ring Stem Seal: Lower O-ring isolates fluid from the stem; upper O-rings allow field replacement under line pressure (applicable for DN less than or equal to 300).
Guided Wedge Design: Integrally cast guide rails maintain low operating torque and prevent rubber friction wear during repeated open/close cycles.
Electrostatic Epoxy Coating: FBE powder applied via fluidized bed immersion on pre-heated castings (greater than 200 degrees Celsius), passing rigorous 3000-hour salt spray corrosion tests.
Applications
Municipal Water Supply: Potable water transmission mains and municipal distribution networks.
Wastewater & Sewage: Treatment plant piping and sewage lift stations (utilizing NBR wedge and SS316 stem variants).
HVAC Systems: Chilled and condenser water loops in commercial and industrial cooling plants.
Fire Protection: Fire water supply loops compliant with FM/UL project specifications (upon request).
OEM & Customization
Equipped with in-house 3D molding simulation, medium-frequency induction furnaces, and CNC vertical machining centers, we support full project-specific customization for global distributors and system integrators:
Dimensional Adjustments: Non-standard face-to-face lengths or specialized multi-standard flange drillings (ANSI, BS, JIS).
Material Upgrades: SS304/SS316 stems, nickel-aluminum bronze stem nuts, or Viton seals for aggressive media environments.
Actuation Integration: Direct mounting pads matching pneumatic, hydraulic, or electric actuators (Auma, Rotork, or local drives).
Private Labeling: Custom body logos, heat-number casting stamping, and tailored nameplate marking.
Testing, Quality & Documentation
Every resilient seated gate valve undergoes strict factory acceptance testing (FAT) prior to shipment in compliance with EN 12266-1 and ISO 5208:
Shell Test: 1.5 times PN (hydrostatic test verifying casting structural integrity).
Seat Test: 1.1 times PN (verifying bidirectional zero-leakage sealing performance).
Operational Torque Test: Validating smooth opening and closing under rated working pressure.
Traceability: Heat numbers are permanently stamped on bodies and bonnets, directly linked to in-house spectrometer chemical analysis and mechanical tensile test reports.
Standard Documentation Provided with Shipment:
EN 10204 3.1 Material Test Certificate (MTC)
Pressure Test Report
Coating Thickness & High-Voltage Holiday Detection Report
Operation and Maintenance (O&M) Manual
FAQ
Q: What is the standard thickness and specification of the epoxy coating?
A: The fusion-bonded epoxy (FBE) coating complies with GSK guidelines, maintaining a minimum dry film thickness of 250 microns and verified for zero pinholes using a 3kV high-voltage holiday detector.
Q: Can the stem O-rings be replaced while the pipeline is under pressure?
A: Yes, for valves sized DN50 through DN300, the upper stem design allows safe O-ring replacement without draining the pipeline.
Q: What is your standard lead time for bulk project orders?
A: Standard specifications (DN50 to DN300, PN16) are maintained in semi-finished inventory, allowing dispatch within 15 to 25 days. Container-load schedules are confirmed upon order placement.
Q: Do you accommodate third-party inspection agencies?
A: Yes, we routinely coordinate inspections with SGS, BV, TUV, or client-appointed third-party agencies at our facility prior to final crating.
Request a Quote / RFQ Submission
To receive a precise technical proposal and competitive commercial quotation, please ensure your inquiry includes the following project parameters:
1.Nominal Diameter (DN) and Pressure Rating (PN / Class)
2.Operating Medium and Working Temperature
3.Operation Type (Handwheel, Gearbox, or Actuator-ready top flange)
4.Required Quantity and Destination Port
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