| 摘要 |
<p>A seal assembly containing a plurality of nonelastomeric sealing elements for use in a valve actuator is disclosed. The valve actuator can be incorporated into a fluid transmission conduit at the surface of a producing oil or gas well. A spring member radially biases one sealing element into engagement with concentric tubular members. Additional sealing elements are radially expandable when subjected to axial compression to close any gap along the surfaces of the concentric tubular members to provide extrusion resistance, greater sealing performance, and fire resistant capability. The seals can be used under hostile conditions, such as extreme temperature and in the presence of corrosive fluids and corrosion inhibitors.</p> |
