Abstract: A fire-safe rotary valve seat assembly for use in pressurized fluid systems subject to fire risk, the seat assembly having both a metal seat ring and an annular resilient non-metallic seal member to provide essentially zero fluid leakage at normal operating temperatures, and the metal seat ring to provide an extremely low rate of fluid leakage in the event high temperature should destroy the flexible seal member. The metal seat ring includes an annular groove around its radially inward face with a pair of flexible lips forming the walls of the groove, and the annular resilient seal member is mounted in the groove between the lips. The lips and the annular resilient seal member both engage a sealing surface on the circumference of a metal valve disc to provide a primary seal for the valve. If the annular resilient seal member is destroyed, the metal lips continue to provide an undamaged secondary seal.

Abstract: An annular valve seat having a resilient metal seal for use in a variety of types of valves provides positive control of fluid flow, with effective metal-to-metal sealing, long life and easy replacement of the seal. The metal seal is in the form of an annular ring comprising approximately one-quarter of a torus that cooperates with the valve's flow control element to establish a metal-to-metal fluid seal which is especially useful at relatively high temperatures. A first edge portion of the torus is held in position against a radial surface of the valve's body by a retainer ring which centers the torus about the flow control element. When the valve is closed the flow control element presses against the outside portion of the resilient metal torus forcing the free edge of the torus against a portion of the retainer ring so that the seal is loaded as a structural span supported at the ends by the valve's body and the retainer ring.

Abstract: A rotary valve for providing control of fluid flow throughout a wide range of pressures and temperatures. The valve includes a pressure-sensitive and temperature-responsive flexible annular seat that cooperates with the valve's flow control element to establish a fluid seal, and a temperature-responsive rigid energizer ring for maintaining both a radial and an axial load on the seat through a wide range of ambient and low temperatures. The valve seat includes an annular, radially outward extending support leg that is held in position against a radial surface of the valve's body by the energizer ring, at least one outer annular sealing lip that extends in a generally axial direction from the leg, and a central sealing lip that extends radially inwardly from the support leg toward the flow control element.

Abstract: A rotary valve for providing control of fluid flow throughout a wide range of pressures and temperatures. The valve includes a pressure sensitive and temperature responsive annular yieldable seat that cooperates with the valve's flow control element to establish a fluid seal, and a temperature responsive rigid energizer ring for maintaining both a radial and an axial load on the seat at all temperatures. The valve seat includes an annular, radially outwardly extending leg that is held in position against a radial surface of the valve's body by the energizer ring, and at least one pressure sensitive annular sealing lip that extends in a generally axial direction from the leg and in contact with the valve's flow control element when the valve is closed. The energizer ring has a generally wedge-shaped cross-sectional configuration and is held in position in the valve body by a retainer ring that is releasably secured, as by screws, to the valve body for quick and easy servicing of the seat.