Back to results
US 6,619,696 B2Granted
Expandable locking thread joint
AssigneeBaker Hughes Incorporated
InventorsJohn L. Baugh, Michael Carmody
Life of this patent
Estimating the term…
Abstract
A thread for expandable downhole tubular connections is disclosed. It features a locking pattern on the pin and box, which engages upon expansion of the connection. The locking pattern compensates for longitudinal shrinkage away from a torque shoulder, as a result of expansion. A resilient seal can be incorporated into the design with pin to box clearance disappearing around the seal as a result of expansion. Resilient seals can be used in tandem to trap atmospheric pressure between them. The wellbore hydrostatic pressure helps engage the locking feature by pushing the box into the pin, helped by the trapped low pressure between the seals.
Claims20
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- and
- a locking surface treatment on one of said inner and outer surfaces that comes into contact with an opposing surface solely by radial expansion of said pin in said box after they are torqued together.
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- and
- a locking surface treatment on one of said inner and outer surfaces that comes into contact with an opposing surface solely by radial expansion of said pin and said box after they are torqued together;
- and
- at least one seal protruding from at least one of said inner and outer surfaces and engaging the other of said inner and outer surfaces as said pin and box are made up, whereupon radial expansion of said pin and box.
2 more elements
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- and
- a locking surface treatment on one of said inner and outer surfaces that comes into contact with an opposing surface solely by radial expansion of said pin and said box after they are torqued together;
- and
- at least two seals protruding from at least one of said inner and outer surfaces and engaging the other of said inner and outer surfaces as said pin and box are made up to define an enclosed annular cavity trapping the ambient pressure upon makeup of said pin and said box, whereupon being subjected to external hydrostatic pressure downhole, said inner surface moves toward said outer surface to move said surface treatment toward a locking engagement of said pin and said box.
2 more elements
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- and
- a locking surface treatment on one of said inner and outer surfaces that comes into contact with an opposing surface solely by radial expansion of said pin and said box after they are torqued together;
- and
- said surface treatment comprises a diamond pattern.
2 more elements
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- and
- a locking surface treatment on one of said inner and outer surfaces that comes into contact with an opposing surface solely by radial expansion of said pin and said box after they are torqued together;
- said surface treatment comprises a plurality of projections;
- said projections are disposed on both said inner and outer surfaces so as to lockingly engage upon radial expansion of said pin and box;
- and
- at least one seal protruding from at least one of said inner and outer surfaces and engaging the other of said inner and outer surfaces as said pin and box are made up, whereupon radial expansion of said pin and box after makeup clearance between said outer and inner surfaces on at least one side of said seal is eliminated.
4 more elements
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- and
- a locking surface treatment on one of said inner and outer surfaces that comes into contact with an opposing surface solely by radial expansion of said pin and said box after they are torqued together;
- said surface treatment comprises a plurality of projections;
- said projections are disposed on both said inner and outer surfaces so as to lockingly engage upon radial expansion of said pin and box;
- and
- at least two seals protruding from at least one of said inner and outer surfaces and engaging the other of said inner and outer surfaces as said pin and box are made up to define an enclosed annular cavity trapping the ambient pressure upon makeup of said pin and said box, whereupon being subjected to external hydrostatic pressure downhole, said inner surface moves toward said outer surface to move said surface treatment toward a locking engagement of said pin and said box.
4 more elements
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- at least two seals protruding from at least one of said inner and outer surfaces and engaging the other of said inner and outer surfaces as said pin and box are made up to define an enclosed annular cavity trapping the ambient pressure upon makeup of said pin and said box, whereupon being subjected to external hydrostatic pressure downhole after makeup, said inner surface moves against said outer surface create a locking engagement of said pin and said box.
A connection between a pin and a box of adjacent tubulars, comprising:
- a pin having an outer surface and configured for insertion into a box having an inner surface, said pin and box respectively comprising an engaging area to allow said pin and box to be torqued together;
- at least one seal protruding from at least one of said inner and outer surfaces and engaging the other of said inner and outer surfaces as said pin and box are made up, whereupon radial expansion of said pin and box after makeup, clearance between said outer and inner surfaces on at least one side of said seal is eliminated.
Dependencies are inferred from the claim text.