供应keystone F990F79U791CR气动蝶阀

keystone气动蝶阀F990F79U791CR

The F990 has smooth flow characteristics, abrasion, erosion and corrosion resistance with a crevice free internal contour.

Features & Benefits:
?The one-piece wafer thin disc stem provides the very minimum obstruction to flow.
?Rounded, polished disc edge gives full concentric sealing, lower torques, longer seat life and bubble-tight shut-off.
?Wafer type split-body for easier maintenance.
?Body locating holes provide easy installation and a perfect centring of the valve between the flanges.
?Primary stem sealing by preloaded contact between flatted seat surface and rounded polished disc hub area exceeds the pressure rating of the valve and prevents leakage through shaft area to atmosphere.
?A secondary sealing is provided by the interference fit between shaft and shaft hole in seat at all positions.
?Top bushing absorbs actuator side thrust loads.
?A moulded-in O-ring provides flange sealing and eliminates need for gaskets.
?The seat is field replaceable and fully isolates the body and stem from the flow.
?AS 2129 Table E and ANSI Class 150 end connections as standard. Others available on request.
?The F990 is not recommended for dead end service.
?PED approved for valves 25-300mm.