| 摘要 |
<p>An expanding nipple, externally mounted packer has a body which mounts onto a casing head by way of a tubing spool or the like. The body contains the upper ends of a pair of concentric mandrels which are lowered into the well casing. The outer mandrel has a deformable seal on its lower end and the inner mandrel has an expander on its lower end. Means in the body, responsive to hydraulic pressure, raises the inner mandrel with respect to the outer mandrel so that the expander forces the seal outwards against the casing wall.</p> |
