Pneumatic Triple Eccentric Flanged Butterfly Valve‑Metal Seated

Pneumatic Triple Offset Flanged Butterfly Valve is a high‑performance metal‑seated butterfly valve driven by a pneumatic actuator. Featuring a triple‑offset design and flanged end connections, it is mainly used for pipeline media shut‑off and flow control under high‑temperature, high‑pressure, wear‑resistant and severe service conditions.

Compared with conventional butterfly valves, the triple‑offset structure enables nearly friction‑free or low‑friction movement between the disc and seat during opening and closing. This significantly reduces wear on sealing surfaces and lowers the operating torque of the valve. During closing, the disc gradually compresses the seat via eccentric rotation to achieve reliable metal‑to‑metal sealing. The valve delivers excellent high‑temperature resistance, wear resistance and pressure‑bearing performance.

Operating Principle of Triple‑Offset Metal‑Seated Butterfly Valve：
Opening Stroke: Compressed air enters the pneumatic actuator and generates rotational torque to drive the valve stem. Thanks to the cam‑effect of triple‑eccentric geometry, the disc lifts away from the seat sealing surface at the initial opening stage without rubbing. The disc rotates to a position parallel to the pipeline flow‑path, and the valve is fully open for unobstructed media flow.

Closing Stroke: Upon receiving control signals, the actuator rotates in reverse to turn the disc. Only at the final stage of closing stroke, the conical sealing face of the disc presses tightly against the metal seat to form reliable metal‑to‑metal sealing and shut off media flow.

Automatic Control: Equipped with solenoid valves, limit switches or positioners, the valve realizes automatic on‑off and flow regulation in response to signals from PLC and DCS control systems. Spring‑return single‑acting or double‑acting pneumatic actuators are optional to satisfy different safety control requirements.