US Patent 6959908 Gate valve flexible wedge

A flexible wedge has a pair of pressure retaining plates and a central wedge body therebetween. The pressure retaining plates have inclined seating surfaces on opposed outer faces thereof for mating with corresponding valve seats within the valve body to prevent substance flow therethrough when the gate valve wedge is in the closed position. The central wedge body is disposed between, and integrally links, the pressure retaining plates. The central wedge body defines at least two offset slots which extend partially into the central wedge body from opposed edges thereof and which overlap in a depth-wise direction to define a deflectable web portion between the offset slots.