06059051 is referenced by 123 patents and cites 17 patents.

The present invention is an apparatus for use in drilling operations. It uses an under-reamer having a plurality of elongated arms with cutting elements at the ends of the arms for enlarging a previously drilled borehole drilled by a drill bit. One or more stabilizers in close proximity to the under-reamer provide stability to the under-reamer and the drill bit. The stabilizer could be rotating or non-rotating; and could be positioned between the under-reamer and the drill bit, or above the under reamer or above a directional device on the drillstring. The cutting arms are selectively operable to perform the enlargement. The stabilizer may be provided with members that closely fit the size of the borehole.

Title
Integrated directional under-reamer and stabilizer
Application Number
8/962491
Publication Number
6059051
Application Date
October 31, 1997
Publication Date
May 9, 2000
Inventor
Volker Krueger
Cell
DE
Donald Jewkes
New Orleans
LA, US
Agent
Madan Mossman & Sriram P C
Assignee
Baker Hughes Incorporated
TX, US
IPC
E21B 10/32
E21B 4/02
E21B 7/04
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