Valve has a self-centering seat to keep the seating position optimal in all circumstances.The body groove is deep enough toallow the seat to expand or relocate radially without jamming the disc.

The sealing seat of the PTFE lip seal flexes when it is closed, and it fits tightly with the outer edge of the butterfly plate in the spherical sector

The first contact part between the ball and the sealing ring is made into a cantilever lip, so as to create a buffer between the valve body and the sealing ring