Patent ID: 8590636
Filing Date: 2013-11-26
Classification: E21B,F16D

Abstract:
1. A rotary steerable system, comprising: a drive coupling having a first section adapted for connection within a drill string; a second section adapted for supporting a drill bit; and a flexible joint connecting the first section to the second section for transmitting drilling loads therebetween as the first section is rotated by the drill string and for permitting pivoting of the second section relative to the first section; a tubular sleeve disposed about the flexible joint and at least portions of the first section and the second section, the tubular sleeve being connected to the second section for movement therewith and being sized to permit pivoting movement of the tubular sleeve relative to the portion of the first section disposed therein; at least three actuators carried by the portion of the first section disposed within the tubular sleeve, each of the actuators being adapted for applying a pivoting force to an inner surface of the tubular sleeve when activated, the actuators being spaced substantially evenly apart; and a gate for delivering a force-transmitting medium to activate the actuators when the actuators are moved through a wellbore-referenced window by rotation of the first section with the drill string, the window sized such that at least two of the actuators are activated within the window at all times when the gate delivers the force-transmitting medium, whereby the second section is controllably oriented relative to the first section, wherein the second section rotates at the same speed as the first section and the drill string.