Underground Flow Control Solutions
Buried butterfly valve designed for direct underground installation without valve boxes, featuring extended stem and corrosion-resistant encapsulation for water and wastewater networks.
Product Features
Direct burial design: Eliminates the need for costly concrete valve chambers or manholes, significantly reducing installation costs.
Extended stem configuration: Valve operator remains accessible at ground level while the valve body is buried 1 to 3 meters underground.
Fully sealed stem extension: Multi-layer O-ring seals prevent groundwater ingress and soil intrusion into the operating mechanism.
Corrosion encapsulation: Valve body and gearbox are encapsulated with fusion-bonded epoxy or polyurethane coating, resistant to soil-side corrosion.
Key Technical Specifications
| Item | Specification |
|---|---|
| Valve Type | Buried Butterfly Valve |
| Connection Type | Wafer / Lug |
| Nominal Size | DN200 – DN1600 |
| Pressure Rating | PN10 / PN16 |
| Operating Depth | Up to 3,000 mm below ground level |
| Stem Extension | 300 mm to 1,500 mm (customizable) |
| Operation Type | Manual gearbox with buried extension spindle |
Typical Applications
Urban water supply buried trunk mains
Wastewater collection networks with deep burial requirements
Fire protection water mains buried under roads or pavements
Industrial cooling water loops requiring underground isolation
Irrigation systems where valve boxes are impractical
Pipeline sections under heavy traffic loads where manholes cannot be placed
Materials
Valve body: Ductile iron ASTM A536 / EN GJS-450
Disc: Ductile iron with epoxy coating or SS304 / SS316
Seat: EPDM (drinking water approved) / NBR
Stem: SS420 / SS431 / SS304
Stem extension tube: Carbon steel with epoxy coating inside and outside
Gearbox housing: Cast iron with fusion-bonded epoxy encapsulation
Stem seals: Multiple NBR or FKM O-rings
Installation Steps
Prepare pipeline trench. Check valve condition. Clean connection surfaces. Position valve correctly. Connect to pipeline. Bury completely. Test operation.
Standards
Design and manufacturing: EN 593 / API 609 Category A
Face-to-face dimensions: EN 558 Series 14 or Series 20
Flange drilling: EN 1092-2 / ANSI B16.5 (for lug type)
Top flange for gearbox: ISO 5211
Coating for buried service: EN 14901 / ISO 12944 (C5-M high corrosion protection)
IP rating: IP68 (IEC 60529)
Packaging Details
To guarantee that our products arrive at their destination in the same pristine condition they left our factory, we have implemented a rigorous, multi-layered packaging system. This protocol is designed to withstand the rigors of international shipping, including handling by multiple carriers, potential impacts, and variable climatic conditions.
The foundation of our packaging is the use of strong, custom-built wooden cases. These are not standard crates; they are constructed from thick, kiln-dried timber to ensure structural integrity and to prevent warping or moisture absorption. The internal dimensions are carefully calculated to provide a secure fit for the valve, with additional space allocated for protective cushioning. This robust external shell acts as the first and most critical line of defense against the physical shocks encountered during transit.
Prior to being placed in the case, every valve undergoes a meticulous pre-packaging phase. All critical machined surfaces, flanges, and threaded ends are shielded with durable plastic caps and plugs. This crucial step prevents the ingress of dust, moisture, and other foreign contaminants that could compromise the valve's sealing integrity or internal mechanisms. Furthermore, it protects these precision-finished areas from scratches, nicks, or any form of cosmetic damage that could occur during handling.
After-Sales Service
We provide technical support. We offer installation guidance. We supply spare parts. We respond quickly. We solve problems promptly.
Accessories
Extended spindle with protective tube for depths exceeding 3 meters
Electric or pneumatic actuator with buried control wiring conduit
Gearbox with torque limiter to prevent over-torque during buried operation
Position feedback device (limit switches) with cable extending to ground level
Fusion-bonded epoxy coating for aggressive soil conditions (sulfate or chloride rich)
Polyurethane outer wrap for additional mechanical protection against rocks and debris
Stainless steel fasteners for lug type connections
Performance Testing
Shell strength test: 1.5 times rated pressure for 60 seconds with no visible leakage or deformation
Seat sealing test: 1.1 times rated pressure in both directions with zero detectable leakage
Stem seal test: Air pressure test under water to verify seal integrity of extended stem assembly
Coating integrity test: Holiday detection (spark test) at 1,500 volts for all external epoxy surfaces
Gearbox submersion test: IP68 verification by submerging gearbox at 5 meters for 72 hours
Operational torque test: Measured at ground level handwheel after full assembly
