The plug is shaped like a segment of a cylinder. Tight closure only requires that the plug rotates.
Axial movement is not a concern. No ‘centering’ of the plug is required, unlike round port eccentric plug valves.
Because the plug is cylindrical and eccentrically offset, it will not contact the seat until nearly closed, minimizing wear.
The rubber plug face compresses for tight closure. It will not suffer compression set because the rubber does not deform.
How to Specify
The plug shall have a cylindrical seating surface eccentrically offset from the center of the shaft. Plug shall not contact the seat until at least 90% closed. Spherical shaped plugs are not acceptable.