Metallic seat construction for valves

A metallic seat assembly for a gate valve includes an annular seat pocket around the flow passageways to the valve chamber with a metallic annular seat support member rigidly mounted in the seat pocket and a metallic annular seat member movably mounted inside the seat support member and connected thereto by a resilient and flexible annular metallic member. The resilient annular member is secured continuously around its inner and outer perimeters to the seat support member and the seat member respectively and it functions as a spring to bias the seat member toward the gate and as a seal between the seat member and the supporting member. The resilient and flexible member permits axial movement of the seat member relative to the seat support member and also compensates for thermal expansion and contraction of the seat member and the seat support member relative to each other. The metallic seat member has an integral metallic sealing lip extending from an annular groove around the sealing face of the seat member. The metallic lip has its free end extending beyond the planar sealing face when in the free position and can be deflected completely into the groove upon contact with a movable valve member.