Patent ID: 8708064
Filing Date: 2014-04-29
Classification: E21B

Abstract:
1. A system for drilling a wellbore, comprising: a rotary steerable system comprising: a drill collar having a plurality of activation ports and a plurality of vent ports fixed at circumferential positions with respect to each other, the plurality of activation ports and the plurality of vent ports being oriented to receive fluid flow from a valve opening of a rotational valve, the valve opening being sized to selectively enable the fluid flow through an activation port, through a vent port, or simultaneously through both an activation port and a vent port depending on the angular orientation of the rotational valve with respect to the drill collar; and a plurality of movable steering pads mounted to the drill collar, the plurality of movable steering pads being hydraulically actuated by a fluid selectively directed through the plurality of activation ports, the plurality of vent ports being utilized for telemetry signals via pressure pulses; the rotational valve being positioned in the drill collar to control access of the fluid to the plurality of activation ports for selectively actuating the plurality of movable steering pads and to the plurality of vent ports for providing telemetry signals.