Weatherford/lamb, Inc.

A Craig Mackay

J Eric Lauritzen

Robert Joe Coon

Patrick Glen Maguire

Neil A A Simpson

Khai Tran

Neil Aa Simpson

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. This arrangement reduces the geometric size of the expansion assembly, affording a larger inner diameter for the hollow bore of the expander tool itself.

Expansion assembly for a tubular expander tool, and method of tubular expansion

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. The transition section defines a sloped inner diameter which provides further protection for the sealing surfaces of the polished bore receptacle as tools, fluid, and tubulars are transited downhole through the polished bore receptacle.

Expandable tubular having improved polished bore receptacle protection

Growing community of inventors

Aberdeen, United Kingdom

A Craig Mackay