The Direct Buried Gate Valve is engineered for underground water, sewage, and district heating networks where traditional concrete valve chambers (manholes) are omitted. It withstands heavy soil loads, groundwater immersion, and ground subsidence without surface access interference.
Manufacturing Foundation: Cast in our ISO 9001 certified foundry utilizing medium-frequency induction furnaces and automated resin sand molding lines to ensure uniform wall thickness and zero internal casting defects in pressure-bearing components.
Technical Specifications
|
Parameter |
Specification Details |
|
Size Range |
DN50 to DN1200 (2 inches to 48 inches) |
|
Pressure Rating |
PN10, PN16, PN25 |
|
Working Temperature |
-10C to +120C |
|
Body and Bonnet Material |
Ductile Iron (EN-GJS-500-7 / ASTM A536) |
|
Wedge Material |
Ductile Iron fully encapsulated with EPDM or NBR |
|
Stem Material |
Stainless Steel 420 (SS304 / SS316 available on request) |
|
Corrosion Protection |
Fusion Bonded Epoxy (FBE) coating, internal and external, min. thickness 300 micrometers |
|
Connection Standard |
EN 1092-2 (ISO 7005-2), ASME B16.42 |
|
Operation Type |
Extended square nut, gear box, or electric actuator with sealed extension spindle |
Key Features
Resilient Seated Wedge: EPDM rubber vulcanized onto the ductile iron core delivers bubble-tight shutoff (ISO 5208 Rate A). The smooth, full-bore flow path prevents sediment accumulation.
Triple O-Ring Stem Seal: Upper stem utilizes three independent O-rings preventing exterior groundwater ingress and interior media leakage.
Hermetically Sealed Extension Bonnet: Factory-sealed bonnet interface protected with multi-layer polyurethane sealants, rated for continuous submersion up to 5 meters water column.
High-Strength Forged Stem: Rolled threads provide high tensile strength and low operating torque during cyclic opening and closing under heavy soil loads.
Applications
Municipal Water Distribution: Main transmission pipelines requiring maintenance-free subsurface isolation.
District Heating Networks: Buried hot water lines operating up to 120C with thermal expansion tolerance.
Fire Protection Loops: Underground fire hydrant supply lines compliant with rapid-shutoff requirements.
Sewage and Wastewater: Non-clogging isolation in pressurized municipal effluent lines.
OEM and Customization
Custom Stem Lengths: Telescopic or fixed extension stems engineered to match exact burial depths (1.5 meters to 5.0 meters).
Material Traceability: Heat number casting stamps and material test reports (MTR) provided per production batch.
Private Labeling: Custom body logos, specific RAL color epoxy coatings, and laser-etched stainless steel nameplates.
Testing, Quality and Documentation
Valves undergo factory hydraulic testing prior to dispatch per EN 12266-1 and ISO 5208:
Shell Test: 1.5 x PN (Hydrostatic)
Seat Test: 1.1 x PN (Hydrostatic)
Coating Adhesion Test: Holiday test (high-voltage spark test at 2.5kV) verifying pinhole-free corrosion barriers.
Documentation Supplied: Inspection Certificate 3.1 (per EN 10204), pressure test reports, and installation manuals.
FAQ
Q: Can this valve be installed directly in wet soil without a concrete valve box?
A: Yes. The IP68-sealed internal structure and thick FBE external coating (300 micrometers min) are engineered for direct earth burial without manholes, eliminating civil excavation overhead.
Q: How is the operating torque transmitted from the ground surface?
A: A rigid or telescopic extension spindle connects the valve's top square nut to a street-level surface box, allowing operation via a standard T-key
Q: What is the estimated service life of the FBE coating underground?
A: When installed per specification, the fusion bonded epoxy coating resists soil stress and cathodic disbondment for an estimated 30+ years.
Request a Quote and Technical Proposal
To receive an official quotation and engineering drawings within 24 hours, please provide the following specifications:
Required Parameters for RFQ:
1.Nominal Size (DN / Inch) and Pressure Rating (PN / Class)
2.Estimated Quantity and Destination Port
3.Burial Depth / Extension Stem Length (if applicable)
4.Operating Mechanism (T-key nut, gearbox, or actuator)
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