US 11,988,064 B2
Managed pressure drilling control system with continuously variable transmission
Paul R. Northam, Houston, TX (US); and Walter S. Dillard, Houston, TX (US)
Assigned to WEATHERFORD TECHNOLOGY HOLDINGS, LLC, Houston, TX (US)
Filed by WEATHERFORD TECHNOLOGY HOLDINGS, LLC, Houston, TX (US)
Filed on Sep. 20, 2021, as Appl. No. 17/479,032.
Application 17/479,032 is a continuation in part of application No. 15/375,409, filed on Dec. 12, 2016, granted, now 11,131,156.
Prior Publication US 2022/0003072 A1, Jan. 6, 2022
Int. Cl. E21B 34/02 (2006.01); E21B 21/10 (2006.01); E21B 34/16 (2006.01); F16K 31/04 (2006.01); E21B 21/08 (2006.01)
CPC E21B 34/025 (2020.05) [E21B 21/10 (2013.01); E21B 34/16 (2013.01); F16K 31/047 (2013.01); E21B 21/08 (2013.01); E21B 2200/02 (2020.05)] 21 Claims
OG exemplary drawing
 
1. An apparatus for use with a subterranean well, the apparatus comprising:
a choke comprising a flow restrictor which is displaceable between a closed position and a fully open position; and
an actuator configured to displace the flow restrictor between the closed and fully open positions at a variable actuation rate by variation of a rotational speed of the actuator based on a position of the flow restrictor, in which the rotational speed of the actuator is slower when the flow restrictor is proximate the closed position than when the flow restrictor is proximate the fully open position.