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US 4,903,777 AGranted
Dual seal packer for corrosive environments
AssigneeBaker Hughes Incorporated
InventorsHenry J. Jordan, Jr., Frank X. Mooney, John L. Baugh, Charles A. Ledet
Life of this patent
Estimating the term…
Abstract
A dual seal packer is shown having a central mandrel which carries upper and lower seal assemblies which straddle an outer cage assembly. Rocker type slips are carried in the cage assembly and are set by a single expander ring. Special support surfaces on the slips cooperate with mating support surfaces on the cage assembly to provide support for the slips under tensive and compressive loading. The slips and upper and lower seal assemblies are set in a single step operation by rotating the mandrel to the right while holding tension on the well string from the surface.
Claims22
A dual seal packer adapted to be releasably set within a surrounding conduit in a well bore, comprising:
- a central mandrel having upper connecting means for connection in a well string extending to the well surface;
- a cage assembly circumscribing the mandrel at one axial location;
- a lower seal assembly carried on the mandrel below the cage assembly and above a lower abutment;
- an expander ring carried about the mandrel above the lower seal assembly, the expander ring having a compression surface for contacting the lower seal assembly and an oppositely arranged, tapered cone surface, the lower seal assembly being expansible radially outward upon contact with the compression surface of the expander ring between a retracted position and an extended position in engagement with the surrounding conduit;
- a plurality of rocker type slips carried by the cage assembly at spaced circumferential locations above the expander ring, each slip having a length defined by opposing ends thereof, an upper serrated gripping surface at one of said opposing ends and an unserrated drag block surface at the other of said opposing ends, each slip having a tapered lower surface for engagement with the cone surface of the expander ring, an oppositely tapered support surface, and a pivot point which allows the slip to pivot between a retracted position and an extended gripping position in which the serrated gripping surface of the slip engages the surrounding conduit, the cage assembly being provided with a mating support surface for engaging the support surface of each slip when the cone surface of the expander ring engages the tapered lower surface of the slip and the slip moves to the extended, gripping position;
- and
- an upper seal assembly carried on the mandrel above the cage assembly and below an upper abutment.
4 more elements
A dual seal packer adapted to be releasably set within a surrounding conduit in a well bore, comprising:
- a central mandrel having upper connecting means for connection in a well string extending to the well surface;
- a cage assembly circumscribing the mandrel at one axial location;
- a lower seal assembly carried on the mandrel below the cage assembly and above a lower abutment;
- an expander ring carried about the mandrel above the lower seal assembly, the expander ring being axially slidable with respect to the lower seal assembly, having a compression surface for contacting the lower seal assembly, and an oppositely arranged, tapered cone surface, the lower seal assembly being expansible radially outward upon contact with the compression surface of the expander ring between a retracted position and an extended position in engagement with the surrounding conduit;
- a plurality of rocker type slips carried about the mandrel at spaced circumferential locations above the expander ring, each slip having a length defined by opposing ends thereof, an upper serrated gripping surface at one of said opposite ends and an unserrated drag block surface at the other of said opposing ends, the slips being carried within windows provided in the cage assembly, each slip having a tapered lower surface for engagement with the cone surface of the expander ring, an oppositely tapered support surface, and a pivot point which allows the slip to pivot between a retracted position and an extended gripping position in which the slip serrated gripping surface engages the surrounding conduit, the cage assembly being provided with a mating support surface located at the approximate pivot point of each of the slips for engaging the support surface of each slip when the cone surface of the expander ring engages the tapered lower surface of the slip and the slip moves to the extended, gripping position;
- and
- an upper seal assembly carried on the mandrel above the cage assembly and below an upper abutment.
4 more elements
A dual seal packer adapted to be releasably set within a surrounding conduit in a well bore, comprising:
- a central mandrel having an external surface and upper connecting means for connection in a well string extending to the well surface;
- a cage assembly circumscribing the mandrel at one axial location;
- a lower seal assembly carried on the mandrel below the cage assembly and above a lower abutment;
- an expander ring carried about the mandrel above the lower seal assembly, the expander ring being axially slidable with respect to the lower seal assembly, having a compression surface for contacting the lower seal assembly, and an oppositely arranged, tapered cone surface, the lower seal assembly being expansible radially outward upon contact with the compression surface of the expander ring between a retracted position and an extended position in engagement with the surrounding conduit;
- a plurality of rocker type slips carried about the mandrel at spaced circumferential locations above the expander ring, each slip having a length defined by opposing ends thereof, an upper serrated gripping surface at one of said opposing ends and an unserrated drag block surface at the other of said opposing ends, the slips being carried within windows provided in the cage assembly, each slip having a tapered lower surface for engagement with the cone surface of the expander ring, an oppositely tapered support surface, and a pivot point which allows the slip to pivot between a retracted position and an extended gripping position in which the serrated gripping surface of the slip engages the surrounding conduit, the cage assembly being provided with a mating support surface located at the approximate pivot point of each of the slips for engaging the support surface of each slip when the cone surface of the expander ring engages the tapered lower surface of the slip and the slip moves to the extended, gripping position;
- an upper seal assembly carried on the mandrel above the cage assembly and below an upper abutment;
- and
- the central mandrel having upper and lower externally threaded regions which are spaced apart on the mandrel exterior surface, the upper threaded region being engagable with an internally threaded running ring when the seal assemblies and slips are in the retracted position and wherein the lower threaded region is engagable with an internally threaded setting ring when the seal assemblies and slips are in the extended position.
5 more elements
A method of setting a dual seal packer within a surrounding conduit in a well bore, comprising the steps of:
- providing a central mandrel having an external surface and upper connecting means for connection in a well string extending to the well surface;
- providing a cage assembly circumscribing the mandrel at one axial location;
- locating a lower seal assembly on the mandrel below the cage assembly and above a lower abutment;
- providing an expander ring carried about the mandrel above the lower seal assembly, the expander ring being axially slidable with respect to the lower seal assembly, having a compression surface for contacting the lower seal assembly, and an oppositely arranged, tapered cone surface, the lower seal assembly being expansible radially outward upon contact with the compression surface of the expander ring between a retracted position and an extended position in engagement with the surrounding conduit;
- providing a plurality of rocker type slips carried about the mandrel at spaced circumferential locations above the expander ring, each slip having a length defined by opposing ends thereof, an upper serrated gripping surface at one of said opposing ends and an unserrated drag block surface at the other of said opposing ends, the slips being carried within windows provided in the cage assembly, each slip having a tapered lower surface for engagement with the cone surface of the expander ring, an oppositely tapered support surface, and a pivot point which allows the slip to pivot between a retracted position and an extended gripping position in which the serrated gripping surface of the slip engages the surrounding conduit, the cage assembly being provided with a mating support surface located at the approximate pivot point of each of the slips for engaging the support surface of each slip when the cone surface of the expander ring engages the tapered lower surface of the slip and the slip moves to the extended, gripping position;
- locating an upper seal assembly on the mandrel above the cage assembly and below an upper abutment;
- providing the central mandrel with upper and lower externally threaded regions which are spaced apart on the mandrel exterior surface, the upper threaded region being engagable with an internally threaded running ring when the seal assemblies and slips are in the retracted position and wherein the lower threaded region is engagable with an internally threaded setting ring when the seal assemblies and slips are in the extended position;
- running the mandrel into position on the well string;
- rotating the well string to the right while holding tension on the string to release the running ring and allow the mandrel to slide upwardly with respect to the cage assembly;
- and
- continuing to pull tension on the string to engage the lower threaded region with the setting ring.
8 more elements
A rocker type slip for use in a well packer of the type having a cage assembly with window openings for receiving a slip, each rocker type slip comprising:
- a slip body having a length defined by opposing ends thereof, an upper serrated gripping surface at one of said opposing ends, a tapered lower surface, an oppositely tapered support surface, and a pivot point which allows the slip to pivot between a retracted position and an extended gripping position in which the slip engages the surrounding conduit, and wherein the support surface of the slip is formed at an angle which is complimentary to a mating support surface provided on the cage assembly, engagement of the slip and cage support surfaces serving as the contact point for resisting axial loads imposed upon the slip in one axial direction.
Dependencies are inferred from the claim text.