Drill bit with adjustable side force

摘要

A drill bit is disclosed. The drill bit includes a center member configured to rotate at a first speed and an outer member disposed outside the center member, wherein the outer member is configured to rotate at a second speed. The drill bit also includes a first cutter disposed on the center member and a second cutter disposed on the outer member, wherein the first speed and second speeds are configured to control a resultant side force of the drill bit.

主权项

1. A drill bit, comprising:
a center member having a first rotational imbalance and configured to rotate at a first speed to cause a first side force resulting from the first rotational imbalance; an outer member disposed outside the center member, wherein the outer member has a second rotational imbalance and is configured to rotate at a second speed to cause a second side force resulting from the second rotational imbalance; and a gear mechanism with an adjustable gear ratio configured to provide power from the outer member to the center member to rotate the center member at the second speed, wherein the first speed and the second speed provided by the gear mechanism combine to provide a resultant side force that controls a drilling direction of the drill bit, and the adjustable gear ratio is adjusted during formation of a wellbore.