| 摘要 |
<p>Power sub (10) comprises a sub (12) having a tubular body (18) provided with screw threads (20) and (22) at opposite axial ends. Transmission system (14) is coupled with the sub (12) and is capable of transferring torque from a motor (24) to the sub (12) to cause rotation of the sub (12) about its longitudinal axis. Sub (12) and transmission system (14) are retained within the housing 16 with the first and second screw threads (20) and (22) being accessible from outside of the housing. Motor 24 may be either permanently held within housing (16), or detachably coupled to the housing and engagable with the transmission system (14).</p> |
