| 摘要 |
<p>A directional drilling tool is provided, which comprises a first end (2) attachable to a drill string, and a second end (4) attachable to a drill bit. A swivel section (6) is provided intermediate the first and second ends (2,4) and has a first swivel member (18) non-rotatably attached to the first end (2) and a second swivel member (20) rotatably coupled to the first swivel member (18) and rotatable relative thereto about a first axis of rotation which is co-axial with a longitudinal axis (LI) of the tool. A first actuator is adapted to selectively rotate the second swivel member (20) about the first axis of rotation. An adjustable bend section (12) has a first bend member (118) non-rotatably attached to the second swivel member (20) and a second bend member (120) rotatably coupled to the first bend member (118), where the first bend member (118) is co-axial with the longitudinal axis (LI), and the second bend member (120) is rotatable relative to the first bend member (118) about a second axis of rotation (R) which is at a non-zero angle relative to the longitudinal axis (LI). A second actuator is adapted to selectively rotate the second bend member (120) about the second axis of rotation (R). A directional drilling system incorporating the tool, a control process for the tool, and a motor drive for rotating a second body relative to a first body are also provided.</p> |
