Butterfly valve construction having a composite seat

Abstract From the Canadian patent

A butterfly valve having a composite reinforced seat, the valve having a one piece body defining a radially inwardly extending annular rib, the valve seat being a Ushaped annular member of a generally resilient material and having a radially outwardly opening channel which engages the rib of the valve body to provide an interlocking engagement between the valve seat and the valve body the, seat including a series of generally U-shaped structural members made of a material more rigid than the resilient material of the seat, the U-shaped member being bonded to the seat, the U-shaped members being spaced sufficiently to permit distortion of the seat so that it can be inserted in the valve body.