| 摘要 |
<p>The present invention provides a torsional energy control assembly and method for eliminating slip-stick and/or drill bit oscillations comprising axial and/or rotational oscillations. In one preferred embodiment, the assembly permits slippage between an upper portion of the drilling string and a lower portion of a drill string. The rotational control assembly may be installed at any desired position in the drill string. The rotational control assembly could also be utilized as a component of other drilling mechanisms such as a downhole drilling motor. The rotational control permits slippage while drilling for a selected time or selected rotational distance or other criteria to thereby release torsional energy in the drilling string which otherwise may produce damaging slip-stick torsional oscillations such as slip-stick. The rotational control assembly may, in one embodiment, comprise an on-off clutch whereby torque is either substantially completely transmitted or substantially not transmitted through the assembly for brief periods.</p> |
