The Double Eccentric Butterfly Valve is a high-performance, resilient seated valve designed for reliable shut-off and control in modern water and industrial piping systems. Constructed with a GGG40/50 ductile iron body and disc, it delivers exceptional impact and tensile strength for long-term structural integrity. Its proven double offset disc design greatly reduces operating torque, minimizes friction during opening and closing, and achieves low-torque operation while extending service life.
The valve features a block-moulded, one‑piece T‑shaped EPDM sealing ring as standard, with optional NBR or Viton available. This solid sealing structure ensures stable drop‑tight closure and greatly improves service life. A key advantage is tool‑free, in‑line maintainability: the sealing ring can be replaced quickly by removing only the retaining ring bolts, without extracting the valve from the pipeline or removing the disc from the body.
For superior sealing and durability, the valve is equipped with a precision‑machined SS304/316 stainless steel welding seat applied via automatic welding and fine milling. When fully closed, the disc seal applies uniform pressure across the entire seat surface. Dual O‑rings on both shafts provide reliable shaft sealing, while bronze and self‑lubricating PTFE/bronze composite bearings offer excellent wear and corrosion resistance. The double‑shaft design reduces pressure loss and improves energy efficiency, with bearing O‑rings protecting pin holes from corrosion; a dry shaft configuration is available on request.
The valve is easy to operate using a self‑locking gearbox with a mechanical position indicator. It is lightweight, compact, and simple to install, with balanced lifting holes for convenient handling and mounting. Both interior and exterior surfaces receive a 250‑μm fusion‑bonded epoxy coating (RAL 5017 blue) complying with WRAS for potable water applications; thicker coatings are available if required.
All rubber components are certified safe for drinking water. The valve uses stainless steel A2 fasteners and stainless steel shafts, with threaded connections sealed by O‑rings to prevent internal and external corrosion. Shaft ends are securely retained with end covers or fully encapsulated designs depending on nominal diameter. The valve is bi‑directional per EN1074‑2 and tested hydrostatically to EN 12266‑1 (shell: 1.5 × PN; seat: 1.1 × PN). It supports direct mounting of electric or pneumatic actuators on the ISO top flange, and extended spindles are available. With a virtually maintenance‑free design for both valve and gearbox, it combines high reliability, long service life, and low operating costs for water supply and general industrial systems.
