| 摘要 |
<p>A mandrel arrangement is for use in a wellbore tubing. A method is for using the same. A mandrel body houses at least one piston, the at least one piston being movable in relation to the mandrel body between a first position and a second position by a fluid force acting on the piston. A cavity is arranged adjacent the piston for communicating wellbore fluid pressure between the wellbore tubing and the piston. The cavity is provided with drainage means for facilitating removal of any particles present in at least a lower portion of the cavity.</p> |
