US 11,852,015 B2
Rotary steerable drilling system
David Cramer, Calgary (CA)
Assigned to SPARROW DOWNHOLE TOOLS LTD., Calgary (CA)
Appl. No. 17/603,722
Filed by Sparrow Downhole Tools Ltd., Calgary (CA)
PCT Filed Apr. 15, 2020, PCT No. PCT/CA2020/050503
§ 371(c)(1), (2) Date Oct. 14, 2021,
PCT Pub. No. WO2020/210905, PCT Pub. Date Oct. 22, 2020.
Claims priority of provisional application 62/888,197, filed on Aug. 16, 2019.
Claims priority of provisional application 62/833,792, filed on Apr. 15, 2019.
Prior Publication US 2022/0195803 A1, Jun. 23, 2022
Int. Cl. E21B 7/06 (2006.01); E21B 34/06 (2006.01); E21B 34/16 (2006.01); E21B 49/00 (2006.01)
CPC E21B 7/06 (2013.01) [E21B 34/066 (2013.01); E21B 34/16 (2013.01); E21B 49/00 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A steerable bottom hole assembly (BHA) comprising:
a drill string component incorporating an actuator subsystem, the actuator subsystem comprising an actuator having an output shaft for selectively rotating a valve plate 66 about a rotational axis of the BHA ; the actuator subsystem further comprising:
a position marker on the output shaft;
a position sensor proximate the output shaft, wherein the position sensor and the position marker interact when the position marker is rotated with the output shaft to a position adjacent the position sensor, the position sensor in response signalling the actuator subsystem for use in controlling the rotational orientation of the valve plate;
the BHA assembly further comprising a bias subsystem extending between the drill string component and a drill bit 36, the bias subsystem receiving a flow of pressurized drilling fluid via the drill string component and comprising:
a housing;
a plurality of hydraulic thrust structures associated with a periphery of the housing;
a plurality of central valve conduits in the housing to convey drilling fluid for actuating a respective one of the hydraulic thrust structures; and
a plurality of peripheral flow conduits in the housing to convey drilling fluid to the drill bit, the flow conduits being closer to the periphery than the central valve conduits
wherein, in accordance with a selected rotational orientation of the valve plate with respect to the valve conduits, pressurized drilling fluid is selectively permitted, or blocked from, entry into the valve conduits.