| 摘要 |
In one aspect, a drill bit is disclosed that in one embodiment includes a pad configured to extend and retract from a surface of the drill bit, a pad on a face of the drill bit configured to extend and retract from the face, and a force application device configured to extend and retract the pad, the force application device including a hydraulically-operated rotating member coupled to speed reduction device configured to apply force on drive unit that applies force on the pad to cause the pad to extend from the drill bit face. In one aspect, the hydraulically-operated rotating member is a propeller operated by a fluid flowing through the drill bit. |
