Wellbore system having an annulus safety valve
AssigneeSilverwell Technology Limited
InventorJoel David Shaw
Life of this patent
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Abstract
An annulus safety valve assembly for controlling gas flow in a wellbore annulus that includes a passage, a check valve in the passage, and an actuator that is selectively changed between first and second states. The actuator is bi-stable, and requires no energy to remain in either state. When the actuator is put into one of the states, the check valve configuration is changed from one way flow to two way flow. Reconfiguring the check valve into the two way flow configuration vents lift gas from inside the annulus that is below the check valve.
Claims17
A system for use with a wellbore comprising:
- an annulus defined between tubulars disposed in the wellbore;
- and
- an annulus safety valve disposed in the annulus that comprises,
- a body,
- a bistable actuator selectively changeable between deployed and retracted operational states, and
- a check valve that is selectively changeable between an open position and a closed position, and that is maintained in the open position when the bistable actuator is in the deployed operational state.
A method of operating a wellbore comprising:
- handling lift gas in an annulus of the wellbore in which an annulus safety valve is disposed and that comprises
- a body,
- a passage in the body,
- a check valve in the passage, and
- an actuator;
- venting from the wellbore by providing a supply of electricity to the actuator to change the actuator from a retracted configuration to a deployed configuration which biases the check valve into an open position;
- removing the supply of electricity to the actuator;
- and
- maintaining the actuator in the deployed configuration while the actuator is isolated from a power source.
Dependencies are inferred from the claim text.