Butterfly valve with wetted parts in contact with the fluid completely coated with PTFE (Teflon) material.
This PTFE butterfly valve is a reliable valve that is resistant to highly corrosive and aggressive fluids. It is especially recommended for severe services where high performance is required.
Spherical closure design, similar to that of a ball valve, achieving continuous closure around the entire contact perimeter between the seat and the disc, without any interruption.
Fundamentally, the high rigidity and little or no flexibility and recovery of the seat have been taken into account. For this reason, high-precision machining of all components, both dimensional and geometric, is required, as well as constant pressure across the entire contact surface between the seat and the disc, which guarantees a long-lasting tight seal and facilitates the memory effect of the seat.
The following solutions have been adopted for this purpose:
In the shaft area: a set of preloaded washers housed in the valve body act on the shafts as they pass through, providing constant dynamic force in any position of the disc.
In the contact area between the seat and the periphery of the disc: to ensure constant, positive pressure on the disc when the valve closes, a highly elastic, fast-recovery elastomer is fitted between the valve body and the seat.
Body/Shaft Sealing: designed to protect against any contamination to the atmosphere. This is achieved by means of Viton® O-rings housed in separate parts, so as not to weaken the shafts or create assembly complications. The closed body design at the lower shaft passage minimizes the risk of leaks to the atmosphere.