Optimal design of seat assembly of bidirectional sealing butterfly valve

    In general, in order to achieve the function of two-way sealing of the butterfly valve, the valve seat of the two-way sealing butterfly valve will adopt a floating structure. According to its working principle, we know that this structure has very high requirements on the spring. If the spring force is too small, Because the thrust of the spring pushing the valve seat is too small, the sealing specific pressure of the sealing pair is not enough, and leakage occurs. If the elastic force of the spring is too large, it will cause the friction between the sealing pair to be too large and accelerate the wear of the sealing surface. The service life of the two-way sealing butterfly valve is reduced. So it needs to be improved.

    The optimal design scheme of the valve seat based on the working principle of the two-way sealing butterfly valve:

    1. The valve seat still adopts a floating structure, so that it can float along the valve axis.

    2. An O-ring is provided between the matching steps of the valve body and the valve seat (metal O-rings can be used for high temperature and high pressure).

    3. Machining a groove on the valve body on the right side of the valve seat, installing a retaining ring in the groove, installing a pressure ring between the retaining ring and the valve seat, and processing a clearance fit with the retaining ring at the outer circle on the right side of the pressure ring Steps restrict the pressing ring to move to the right.

    4. The threaded through hole is machined on the pressure ring, and the position of the valve seat is adjusted or restricted by the inner hexagonal screw.