Triple eccentric butterfly valve uses a metal hard sealing structure and is widely used in the fluid pipeline system of water supply and drainage, sewage, construction, petroleum, chemical, paper, hydropower, metallurgy, etc. for regulation and interception of two-way interchangeable medium conveying process. It has a high sealing performance and is suitable for various corrosive and non-corrosive media working conditions. More info: https://www.shiphamvalves.com/solution-category/triple-offset-butterfly-valves/

It is different from the concentric or double offset butterfly valve in that the third offset design on the seat/seal ring eliminates all rubbing of the valve seat and seal ring during opening/closing operation. As a result, the seating surfaces are exposed to less friction and wear, extending their operating life.

The Importance of Proper Installation and Maintenance of Triple Eccentric Butterfly Valves

The seat/seal ring has an inclined conical profile machined into it. The angled position of the seat/seal ring in relation to the disc allows a full contact surface with the disk when the valve is open. The angled position also minimizes seat damage and preserves the integrity of the sealing surfaces.

During closing, the angle of the seat/seal ring causes it to deviate from its original centered position on the disc and compress against the butterfly plate, forcing the seal ring to deform to a tight fit. As the valve closes, this deformation reaches its maximum and creates a tight bubble shut-off. The angle of the seat/seal ideally matches the angle of the disc to form a perfect seal. This eliminates all interference between the seat and seal ring, preventing rubbing that may cause the seat to stick to the disc during valve travel.