Double flanged, double eccentric,
butterfly valve
Double flanged double eccentric butterfly valve T.I.S. Type is designed to be installed in the pipeline in order to shut off the flow or limit it partially (indeed within certain limits double flange double eccentric butterfly valve could be also used as a control valve). During closing operation, the disc is perpendicular to the flow direction, consequently, to open the valve the disc should be rotated by 90°. The tightness of the valve is guaranteed by an automatic sealing system in the seat: in closed position the operating pressure supports the tight effect pressing the soft sealing ring against the conical seat surface in the valve body in both flow directions.
The double offset design of the valve allows to get two important advantages:
- when the valve is open, the profile sealing ring is completely unstressed
- during opening/closing operations, the disc sealing ring does not apply any friction on the body seat: the operating torque is in this way reduced, and the sealing life is extended.
The valve is suitable for drinking water application: the fusion bonded epoxy process (FBE), with certified resin powders used for internal and external surfaces, guarantees a heavy corrosion protection.
