Abstract: An improved expansion assembly for an expander tool is provided, and a method for expanding a surrounding tubular body within a wellbore. The expansion assembly first comprises a piston disposed within a recess of the expander tool. The top surface of the piston closely receives a body. The bearing body includes one or more races which house at least one bearing. In one arrangement, at least one bearing is provided which rotationally resides within a single race. In another arrangement, a plurality of bearings are provided that recirculate within one or more races. In this arrangement, the bearing body is preferably a tapered, cylindrical roller actuated into contact with the surrounding tubular by hydraulic pressure applied from within the bore of the expander tool. These arrangements reduce the geometric size of the expansion assembly, affording a larger inner diameter for the hollow bore of the expander tool itself.

Abstract: An improved expansion assembly for an expander tool is provided. The expander tool is used to expand a surrounding tubular body within a wellbore. The expansion assembly first comprises a piston disposed within a recess of the expander tool. The top surface of the piston defines a bearing cavity configured to closely receive a roller. A shoe is further disposed on the top surface of the piston to receive a lower portion of the roller. In one arrangement, the roller is a tapered cylindrical roller actuated by hydraulic pressure applied from within the bore of the expander tool. Actuation of the tool forces the pistons to radially extend away from the body of the tool within the recesses. This, in turn, causes the roller members to engage the inner surface of the surrounding tubular body to be expanded. Rotation of the expander tool causes the rollers to at least partially rotate within the bearing cavity.

Abstract: The present invention provides an expandable tubular having improved polished bore receptacle protection. The present invention further provides methods for completing a wellbore through the use of an expandable string of casing having improved polished bore receptacle protection. In one aspect, the invention includes a liner member having an expandable section, and a polished bore receptacle positioned below the expandable section. The expandable section is run into a wellbore, and is positioned to overlap with the bottom portion of a string of casing already set within the wellbore. The expandable section is then expanded into frictional engagement with the surrounding casing. The expandable section optionally includes at least one sealing member and at least one slip member on the outer surface. In one aspect, a transition section is provided between the expandable section and the polished bore receptacle.

Abstract: The present invention provides an expandable tubular having improved polished bore receptacle protection. The present invention further provides methods for completing a wellbore through the use of an expandable string of casing having improved polished bore receptacle protection. In one aspect, the invention includes a liner member having an expandable section, and a polished bore receptacle positioned below the expandable section. The expandable section is run into a wellbore, and is positioned to overlap with the bottom portion of a string of casing already set within the wellbore. The expandable section is then expanded into frictional engagement with the surrounding casing. The expandable section optionally includes at least one sealing member and at least one slip member on the outer surface. In one aspect, a transition section is provided between the expandable section and the polished bore receptacle.

Abstract: A method and apparatus for creating a seal between two coaxial strings of pipe are provided. The method and apparatus have utility in one embodiment for sealing the annulus between the tubing and the casing within a hydrocarbon wellbore. According to the method of the present invention, an expander tool is positioned at a selected depth within the tubing, and then actuated in order to expand the tubing against the inner wall of the casing wall. Multiple configurations of the expander tool are disclosed. The expander tool is rotated in order to provide a fluid seal in the annulus. In this way, the tubing string becomes its own packer. In one embodiment, a seal ring is provided around the outer surface of the tubing to enhance the fluid seal. Further, a slip ring is provided around the outer surface of the tubing to provide a gripping means between the tubing and the casing.

Abstract: An improved expansion assembly for an expander tool is provided. The expander tool is used to expand a surrounding tubular body within a wellbore. The expansion assembly first comprises a piston disposed within a recess of the expander tool. The top surface of the piston defines a bearing cavity configured to closely receive a roller. A shoe is further disposed on the top surface of the piston to receive a lower portion of the roller. In one arrangement, the roller is a tapered cylindrical roller actuated by hydraulic pressure applied from within the bore of the expander tool. Actuation of the tool forces the pistons to radially extend away from the body of the tool within the recesses. This, in turn, causes the roller members to engage the inner surface of the surrounding tubular body to be expanded. Rotation of the expander tool causes the rollers to at least partially rotate within the bearing cavity.