06732817 is referenced by 218 patents and cites 2 patents.

A downhole tool that functions as an underreamer, or alternatively, as a stabilizer in an underreamed borehole. The tool includes one or more moveable arms disposed within a body having a flowbore therethrough in fluid communication with the wellbore annulus. The tool alternates between collapsed and expanded positions in response to differential fluid pressure between the flowbore and the wellbore annulus. In one embodiment, the tool moves automatically in response to differential pressure. In a second embodiment, the tool must be selectively actuated before it is moveable. When the tool expands, the arms are preferably translated axially upwardly, while simultaneously being extended radially outwardly from the body. The expanded tool diameter is adjustable at the surface without changing components. The arms may include borehole engaging pads that comprise cutting structures or wear structures or both, depending upon the function of the tool.

Title
Expandable underreamer/stabilizer
Application Number
10/78067
Publication Number
6732817 (B2)
Application Date
February 19, 2002
Publication Date
May 11, 2004
Inventor
Wei Xu
Houston
TX, US
Charles H Dewey
Houston
TX, US
Agent
Conley Rose P C
US
Assignee
Smith International
TX, US
IPC
E21B 7/28
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