| 摘要 |
<p>A safety valve (100) replaces an existing safety valve (102) in order to isolate a production zone from a tubing string when closed. Preferably the safety valve (100) includes a flow interruption device (106) displaced by an operating conduit extending from a surface location to the safety valve (100) through the inside of the production tubing. A by-pass conduit (150) allows communication from a surface location to the production zone through the safety valve (100) without affecting the operation of the safety valve (100).</p> |
