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US 11,377,917 B2Granted
Staged annular restriction for managed pressure drilling
AssigneeSchlumberger Technology Corporation
InventorsJerod Bushman, Shelby Wayne Carter, Henrix Soto, Jeffrey Ham
Life of this patent
Estimating the term…
Abstract
An apparatus includes a conduit forming part of a drilling fluid return path from a wellbore. The the conduit has at least one well outflow control in the conduit. The at least one well fluid outflow control has at least two annular flow restrictors each separately operable to close to a respective inner diameter.
Claims20
A system, comprising:
- a drill string extending into a wellbore drilled through subsurface formations;
- a pump having an inlet in fluid communication with a supply of drilling fluid, the pump having an outlet in fluid communication with an interior of the drill string;
- a conduit extending from a first position in the wellbore to a second position proximate a surface end of the wellbore, wherein the pumped drilling fluid is configured to be returned upwardly through an annular space between an exterior of the drill string and an interior of the conduit;
- at least one well fluid outflow control comprising a housing disposed along the conduit and at least two annular flow restrictors disposed at distinct axial positions within the housing;
- and
- a control system configured to generate control signals to cause the at least two annular flow restrictors to close to provide successively smaller inner diameters in a direction of the drilling fluid moving upwardly through the annular space.
3 more elements
A method, comprising:
- pumping drilling fluid through a drill string extended into a wellbore drilled through subsurface formations;
- returning the pumped drilling fluid upwardly through an annular space between an exterior of the drill string and an interior of a conduit disposed to a selected depth in the wellbore;
- and
- selectively restricting outflow of fluid from the interior of the conduit by operating at least one well fluid outflow control comprising a housing disposed along the conduit and at least two annular flow restrictors disposed at distinct axial positions within the housing, wherein operating the at least one well fluid outflow control comprises generating control signals to instruct the at least two annular flow restrictors to close to provide successively smaller inner diameters in a direction of the drilling fluid moving upwardly through the annular space.
1 more element
An apparatus, comprising:
- a conduit forming part of a drilling fluid return path from a wellbore, the conduit comprising at least one well outflow control in the conduit;
- wherein the at least one well fluid outflow control comprises at least two annular flow restrictors disposed at distinct axial positions in the conduit and that are separately operable to close to provide successively smaller inner diameters in a direction of the drilling fluid moving upwardly in the return path from the wellbore.
Dependencies are inferred from the claim text.