摘要 |
High temperature seals for use in rotary valves are described herein. An example seal for use with a rotary valve includes a primary seal to engage a flow control member when the primary seal is in a first condition and a secondary seal at least partially disposed within the primary seal. The primary seal is to prevent the secondary seal from engaging the flow control member when the primary seal is in the first condition and the secondary seal is to engage the flow control member when the primary seal is in a second condition. |