Double Eccentric High Performance Wafer Butterfly Valve

Double Eccentric High Performance Wafer Butterfly Valve is an industrial butterfly valve designed with a double‑offset shaft structure. The shaft axis is offset relative to both the valve body centerline and the sealing centerline, which minimizes friction and wear between the disc and seat during opening and closing cycles.

This valve generally adopts a metal disc paired with resilient or high‑performance sealing seat. It features low operating torque, excellent sealing performance, long service life and flexible operation. The wafer‑type connection delivers compact structure, light weight and easy installation. It can be fitted with hand lever, gear operator, electric actuator or pneumatic actuator for manual and automatic control.

Working Principle of Double‑Offset Wafer Butterfly Valve：
Closing Stroke: The actuator drives the valve stem to rotate, and the disc turns towards the closed position. Benefiting from the double‑offset design, the disc comes into contact with the seat and forms sealing only near the fully‑closed position. Unlike conventional concentric butterfly valves, there is no continuous rubbing against the seat throughout the rotation travel. Once the disc is fully closed, a reliable sealing interface is established between disc and seat to block medium flow.

Opening Stroke: The actuator rotates the valve stem in the reverse direction to open the disc. Thanks to the double‑offset geometry, the disc lifts off the seat at the initial stage of opening, minimizing friction and compression on sealing faces. This results in low operating torque and reduced seat wear. When the disc reaches the fully‑open position, it is substantially parallel to the medium flow direction, offering enlarged flow area and low pressure loss.