Why are Triple Eccentric Butterfly Valves More and More Widely Used

Many industries require more and more valves. If double eccentric butterfly valve are required to withstand high temperature, hard seal must be used, but the leakage of hard seal butterfly valves is large; If the valve is required to leak zero, the valve must be soft sealed, but the soft seal butterfly valve is not resistant to high temperature.

In order to overcome the contradiction of double eccentric butterfly valve, the engineer designed the triple eccentric butterfly valve. The structural feature is that the conical axis of the butterfly plate sealing surface is inclined to the cylinder axis of the body while the axis of the valve stem is eccentric. That is, after the third eccentricity, the sealing section of the butterfly plate is no longer true circle, but ellipse, and its sealing surface shape is asymmetric because of this, one side is inclined to the center line of the body, and the other side is parallel to the center line of the body.

The biggest feature of triple eccentric butterfly valve is that the sealing structure has been fundamentally changed. It is not position seal, but torque seal. That is, it is not relying on the elastic deformation of the valve seat, but completely relying on the contact surface pressure of the valve seat to achieve the sealing effect. Therefore, the problem of zero leakage of metal seat is solved at one stroke, and the contact surface pressure is proportional to the medium pressure, Therefore, the triple eccentric butterfly valve is also high temperature resistant.

The valve seat of the three eccentric butterfly valve can be replaced,   And the sealing surface of butterfly plate is independent from butterfly plate,   The sealing surface of butterfly plate can be replaced,   The maintenance cost is greatly reduced.