| 摘要 |
A seal system is provided with a series of annular seal assemblies separated by relatively rigid spacing members and may be preferably adapted to selectively sealing engage a packer apparatus within a well bore conduit, during the completion or workover of a subterranean oil or gas well. Preferably, each seal assembly comprises four annular seal members in sequence. The outermost seal members are formed from a thermoplastic polymer having a coefficient of expansion greater than that of the rigid spacing members and the conduit, with physical resistance to corrosive chemicals and high temperature and pressure environments. The outermost member has a physical hardness sufficient to withstand extrusion into a gap defined between the rigid spacing member and the conduit by pressure transmitted from the rigid spacing member. One of the inner seal members is a flexible perfluoro polymer with enhanced permanent set and cold flow. The second of the inner seal members is an elastomer derived from the copolymerization of tetrafluoroethylene and perfluoroethers.
|
