| 摘要 |
Devices and methods are provided that permit a packer element to be deflated in the event of an emergency wherein power to the inflating pump is lost. An inflatable packer assembly having packer elements are selectively inflated by fluid pumped from the wellbore through an inflation tube into the packer elements. The packer assembly includes a deflation sub that houses the components of the emergency deflation mechanism. The deflation sub defines a dumping chamber that is at approximately atmospheric pressure, retains a portion of the inflation line for the packer elements and a means for separating the inflation line. To actuate the emergency deflation mechanism, an operator pulls up on the tubing string. A piston is then moved axially with respect to the housing, causing separation of the inflation line. Fluid from within the packer elements is then released into the dumping chamber to deflate the packer elements. Because the packer elements are subject to external hydrostatic pressure, the fluid contents will readily flow into the dumping chamber.
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