| 摘要 |
<p>The present invention generally relates to downhole tools. More particularly, the invention relates to a locking mechanism for use on a downhole tool. A flow actuated locking mechanism is provided for a downhole tool that includes an annular, two-position sleeve having an unlocked position and a locked position. A pin assembly within the tool is used to retain the sleeve in the locked position. In one aspect of the invention, the locking mechanism is used on a reaming tool with extendable cutters that are extendable from the body of the tool to increase the diameter of the tool and aid in forming a wellbore therearound. The locking mechanism prevents the cutters from collapsing or closing as the reamer is moved axially in the wellbore.</p> |
