Pneumatic Triple‑Offset Wafer Butterfly Valve, Metal Hard Sealing

Pneumatic Triple‑Offset Metal‑Seated Wafer Butterfly Valve is a high‑performance butterfly valve featuring triple‑offset construction, metal‑to‑metal hard seating and wafer‑type connection. Driven by a pneumatic actuator to rotate the disc, it achieves rapid on‑off and flow control for pipeline media.

By optimizing the offset positions of the stem axis and sealing faces, the triple‑offset structure allows the disc to quickly separate from or approach the seat during opening and closing, which greatly reduces friction and wear between sealing surfaces. Upon closure, the disc gradually compresses against the metal seat along a dedicated offset track to form dependable metal‑to‑metal hard sealing. It delivers advantages of high‑temperature resistance, wear resistance and long service life. The wafer‑type valve body is installed between two pipeline flanges, characterized by compact structure, light weight and easy installation.

Operating Principle of Pneumatic Triple‑Offset Butterfly Valve：
Opening Stroke: After the pneumatic actuator receives an opening signal, compressed air enters the actuator and generates rotary torque to drive the valve stem into rotation. The disc rotates together with the stem and opens gradually. Thanks to the triple‑offset geometry, the disc lifts off the metal seat at the early stage of opening, resulting in minimal friction between sealing surfaces. This reduces operating torque and mitigates sealing‑surface wear. The valve reaches full‑open position when the disc rotates roughly parallel to the pipeline flow passage, allowing smooth media passage.

Closing Stroke: When the control system sends a closing signal, the pneumatic actuator reverses its motion and drives the disc towards closed position. As the disc approaches closure, its sealing face moves toward the metal seat along the triple‑offset track. At the final stage of closing, mechanical wedging effect generated by the offset structure creates sufficient specific sealing pressure between disc and seat. Reliable metal‑to‑metal sealing is achieved to shut off pipeline media effectively.

Automatic Control: Double‑acting or spring‑return single‑acting pneumatic actuators are optional. Solenoid valves are fitted for remote on‑off operation; limit switches provide valve‑position feedback. A valve positioner can be equipped to adjust disc opening for flow regulation. Manual override permits manual operation upon loss of air supply or power failure.