Exotica - Double-Eccentric and Triple-Offset Butterfly Valves

The shaft in double-offset or high-performance valves is slightly displaced with regard to the pipe centreline, which allows for the disc to only slightly interface with the seat when closing. Triple-eccentric butterfly valves have the same characteristics as double-offset valves, in addition to a third factor where the external profile of the disc or vane is machined to a conical shape. The upstream-projected cone faces the valve`s upstream with the cone off-center with regard to the pipe. This is the third offset, which makes this type of butterfly valves triply offset with regard to the pipeline`s centerline.