Kepner’s Flexible Seal Seat design prevents fluid leakage with a seat design that combines metal-to-metal and resilient O-ring seal contact. The seal closes around scratches, dents, and other irregularities to prevent any leakage past the seat. And because the O-ring is securely retained at the seat, rather than on the poppet, it is protected from the destructive abrading and blasting effect of fluid flow. The design not only extends seal life, but also prevents the seat “wire drawing” commonly found in conventional valves.

When closed with no fluid flow, the design’s relaxed O-ring seal and light seal-to-poppet contact guarantees low-pressure sealing and prevents valve chatter. When open with full flow, the seal flexes to close off all external leakage, and the steel enclosure shields the O-ring and keeps it from moving. When closed with reverse pressure, the seal continues to prevent external leakage and flexes around poppet. The higher the reverse pressure, the tighter the seal.

A wide choice of O-ring seal elastomers is offered for system compatibility. The Flexible Seal Seat design is available not only in Kepner’s shuttle valves, but also in check, relief, and pilot-operated check valves (for more on shuttle valves, see "So, You Think You Know Shuttle Valves"). The Flexible Seal Seat’s has seen widespread use for more than 60 years in millions of hydraulic and other fluid-control applications, providing leak-tight sealing (even at low pressures) and no chatter.