摘要 |
A method and apparatus for automatically shutting in a producing well whenever the pressure in the well annulus drops below a defined pressure. A valve is positioned in the production tubing above an isolated production formation in the well and is maintained in an open position in response to the defined pressure in the well annulus. When the defined pressure is lost in the well annulus (e.g. due to intersection by a second well being drilled in the proximity of the producing well), the valve will close to shut in the producing well.
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