High-Integrity Valve Solutions (Group 1)
Explore our export-ready industrial valves, rigorously hydrostatically tested and manufactured with integrated foundry and rubber compounding facilities.
Engineering Fundamentals of WRAS Lug Butterfly Valves
A comprehensive examination of certification requirements, mechanical superiority of lugged architectures, and elastomeric compound formulation.
WRAS Potable Water Certification
The Water Regulations Approval Scheme (WRAS) certifies that non-metallic components contacting potable water do not impart toxicity, alter odor, promote microbial growth, or leach harmful compounds into municipal drinking systems pursuant to BS 6920 standards.
Lugged Architecture vs. Wafer Design
Unlike wafer valves that rely on through-bolts clamped between pipeline flanges, lug butterfly valves feature threaded bolt holes across the perimeter. This enables reliable downstream line disconnection and dead-end isolation while sustaining full differential pressure ratings.
In-House Elastomeric Compounding
Seat life determines valve life. Operating with our dedicated rubber manufacturing division founded in 1987 (Tianjin Dongfang Rubber), our proprietary WRAS-grade EPDM formulations deliver optimized compression set resilience, superior chloramine resistance, and bubble-tight bidirectional zero leakage.
Why China's Integrated Valve Manufacturing Delivers Unmatched TCO
Combining heavy-duty ductile iron casting, advanced polymer vulcanization, and precision CNC milling within a singular industrial park.
Vertical In-House Foundry
Eliminating third-party foundry delays. We pour ductile iron (QT450-10 / GGG40 / GGG50) directly, verifying spectral chemistry and tensile strength prior to any machining processes.
Multi-Axis CNC Machining
High-precision spherical disc profiles and stem drive flats are turned to micron-level tolerances, lowering operational seating torque and extending actuator service lifespan.
Electrostatic Epoxy Coating
Body castings receive fusion-bonded epoxy (FBE) coatings exceeding 250 µm DFT. Certified non-toxic and tested with holiday detectors to ensure zero pinhole corrosion under subterranean service.
Rigorous Factory Testing
Every single valve undergoes bi-directional hydrostatic shell testing at 1.5× PN and seat leakage testing at 1.1× PN according to EN 12266-1 Rate A and ISO 5208 standards.
Engineering Scenarios & Global Procurement Matrix
From district heating and municipal drinking pipelines to seawater intake and desalination networks, our WRAS lug valves deliver certified performance across critical sectors.
Municipal Potable Water Networks
Installed at pump discharge stations, flow meter isolation pits, and distribution mains. The pinless disc design prevents fluid contact with internal stem mechanics, protecting water purity and completely preventing galvanic stem-disc crevice corrosion.
Commercial High-Rise HVAC & District Cooling
Lugged butterfly valves enable isolation of chillers, cooling towers, and heat exchangers without draining the entire vertical riser. Rated for continuous PN16/Class 150 dead-end holding, saving hundreds of maintenance hours during mechanical plant servicing.
Desalination & Seawater SWRO Pre-treatment
For high-salinity and marine applications, our ductile iron bodies can be specified with Aluminum Bronze (C95800) or Duplex Stainless Steel (2205/2507) discs paired with peroxide-cured WRAS EPDM seats to ensure long-term resistance to biofouling and pit corrosion.
| Technical Parameter | Standard Specification | Optional / Engineered Variant | Compliance Standard |
|---|---|---|---|
| Nominal Diameter | DN50 – DN600 (2" to 24") | DN700 – DN1200 (28" to 48") | EN 558 Series 20 / ISO 5752 |
| Nominal Pressure | PN10, PN16, Class 150 | PN25 (High Pressure Water Loop) | EN 12266-1 / ISO 5208 |
| Body Metallurgy | Ductile Iron GGG40 / GGG50 / EN-GJS-450 | WCB Cast Steel, CF8M Stainless | EN 1563 / ASTM A536 |
| Disc Material | SS304 / SS316 / CF8M Mirror Polished | Al-Bronze C95800, Hastelloy, Ceramic | ASTM A351 / EN 10213 |
| Seat Elastomer | WRAS-approved EPDM (-20°C to +110°C) | NBR (Oil/Fuel), High-Temp EPDM, PTFE | BS 6920 / FDA 21 CFR 177.2600 |
| Flange Compatibility | Multi-drilled: EN 1092-2 PN10/16, ASME B16.5 150# | JIS 10K/16K, AS 2129 Table E | EN 1092 / ASME B16.5 |
| Actuator Mounting | Direct Mount ISO 5211 with Double D Stem | Keyed Drive, Spline Drive | ISO 5211 |
Frequently Asked Questions by Global EPC Contractors
Authoritative answers regarding certification scope, testing regimes, and structural engineering selection.
Why is WRAS certification mandatory for potable water valves in the UK and overseas?
Can your WRAS lug butterfly valve handle bi-directional dead-end service safely?
What is the structural difference between concentric pinned and pinless disc designs?
How does your factory control the quality of the EPDM rubber seat?
What inspection documents are supplied with wholesale valve shipments?
High-Integrity Valve Solutions (Group 2)
Explore our heavy-duty industrial check valves, globe valves, and WRAS-approved lug configurations for complete project turnkey procurement.
