triple offset butterfly valve

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Triple Offset Butterfly Valve

A Triple Offset Butterfly Valve is a specialized type of butterfly valve that is designed to provide reliable and bubble-tight shut-off in high-pressure and high-temperature applications. It is called "triple offset" because the valve's sealing mechanism involves three distinct offsets in its design.

The three offsets in a Triple Offset Butterfly Valve refer to the following:

First Offset: The shaft is offset from the center of the valve body, which ensures that the valve disc (also known as the butterfly) makes contact with the seat only at the final stage of closing. This design reduces friction during valve operation, preventing unnecessary wear and tear.

Second Offset: The center of the valve disc is offset from the centerline of the pipe. This offset, combined with the conical shape of the valve seat, allows for a cam-like action during closing. As the disc comes in contact with the seat, it moves perpendicular to the seat's sealing surface, achieving a tight and uniform seal without excessive rubbing.

Third Offset: This offset refers to the cone angle of the sealing surface on the valve disc. The cone angle is different from the cone angle of the valve seat. This design creates a "wedging" effect during closing, ensuring a tight and bubble-tight seal even at high pressures and temperatures.