| 摘要 |
The present invention relates to a subterranean well annulus pressure safety valve. In one embodiment, the valve is full opening to permit complete access therethrough of wireline and other remedial tools, and contains the annulus safety valve members completely offset from the central housing. The invention also relate to an annulus safety valve wherein a series of valve elements are placed exterior of a central housing and may be staged to open in series upon incremental increase of pressure thereacross. The annulus safety valve also provides pressure equalization means to equalize pressure across the valve cluster prior to opening of the cluster. The annulus safety valve also has selectively disengagable sealing plug means therein which may be removed while the valve is in the well to increase total fluid flow area through the valve components of the apparatus. A method of controlling an annular area interior of casing within a well using the annulus safety valve also is disclosed.
|
