ACTUATION SYSTEM WITH LOCKING FEATURE

摘要

A technique facilitates use of an actuator with a locking feature enabling selective locking of the actuator in a desired operational position. For example, the actuator may comprise a mandrel which can be used to shift a tool between operational positions. The mandrel is surrounded by a housing which creates a cavity. A magneto rheological fluid is disposed within the cavity and operates in cooperation with the mandrel to enable selective locking of the mandrel at a desired operational position or positions. Magnetic field can be generated via an electromagnetic coil or a permanent magnet to selectively increase the viscosity of the magneto rheological fluid to lock the mandrel at the appropriate operational position.

主权项

1. A system for controlling actuation, comprising:
a tool string deployed in a wellbore, the tool string comprising:
a shiftable device; andan actuator having a mandrel slidably positioned through a housing and coupled with the shiftable device, the housing containing magneto rheological fluid in a manner such that shifting the mandrel with respect to housing causes movement of the magneto rheological fluid, the actuator further comprising a device for selectively establishing a magnetic field to change the viscosity of the magneto rheological fluid to resist movement of the mandrel relative to the housing.